Mortar peeling method

[Problem]A mortar peeling method which can keep a sound generated during a peeling work to an allowable quiet sound and can peel a mortar off a concrete framework smoothly.[Solution]In a mortar peeling method, by gradually extending a piston rod 42 of a hydraulic jack 13 in a mortar peeling device 10A forward in one direction, a cutter 14 is gradually advanced forward in one direction so as to execute a mortar peeling process of peeling a mortar 21 with a predetermined thickness off a concrete framework 20 by using the cutter 14. In the mortar peeling method, after the piston rod 42 of the hydraulic jack 13 is extended forward in one direction and the mortar 21 is peeled, by retreating the piston rod 42 rearward in one direction, a session of the mortar peeling process is completed.

TECHNICAL FIELD

The present invention relates to a mortar peeling method using a mortar peeling device for peeling mortar constructed on a concrete framework.

In a building, finishing is performed by constructing a mortar having a predetermined thickness on a surface of a concrete framework, but when a renovation work of the mortar after years have passed, an earthquake strengthening work by increasing a thickness of a wall or a ceiling or the like is required, prior to new finishing or thickness increasing, a peeling work of the mortar constructed on the surface of the concrete framework is performed. In the prior-art mortar peeling work, a user demolishes existing mortar by directly performing a chipping work using a small-sized rock drill or a hammer drill. However, since chipping machines such as the small-sized rock drill, a hammer drill and the like destroy mortar by applying vibration and impact to the mortar by feeding in compressed air by using a compressor, it has problems that impact sound is large, and work efficiency is poor. Particularly if the building to be worked is operating on 24 hours a day basis or in the case of schools, hospitals and the like which require silence, a work time slot is largely restricted due to the noise involved in the peeling work, a long time is required for completion of the peeling work, and a high labor cost is incurred by the peeling work, which is a problem.

In the case of these impact/vibration chipping machines, since the impact and vibration are transmitted also to the concrete framework, there is a concern that damage such as a crack is induced in the framework. Moreover, in an earthquake strengthening work, mortar with low strength should be completely removed, and only the concrete framework should be exposed, but it takes a long time to uniformly peel the mortar with those chipping machines performing chipping locally, and the mortar cannot be peeled with high accuracy, which is a problem. Furthermore, when these chipping machines are used, demolished mortar becomes small crushed pieces, a large quantity of fine particles and dusts are generated, and a work environment deteriorates, which is a problem.

In order to solve each of the above described problems, a mortar peeling method described below was proposed (see Patent Literature 1). In this mortar peeling method, for a mortar finished surface on which mortar is constructed with a predetermined thickness dimension on a surface of a concrete framework, a disk-shaped concrete cutter held on a rotating shaft is brought in, and while the rotating shaft is held orthogonally to the concrete framework surface, the concrete cutter is inserted into a boundary portion between the concrete framework and the mortar, and by moving the concrete cutter in parallel with the concrete framework surface, the mortar is cut and separated. This method has an effect that a noise is small and a mortar constructed on the surface of the concrete framework can be demolished in a short period of time.

CITATION LIST

Patent Literature

SUMMARY OF INVENTION

Problem to be Solved by Invention

In the mortar peeling method disclosed in Patent Literature 1, since the concrete cutter is rotated and moved while the mortar is being cut, a cut surface of the mortar and a cutting edge of the cutter rub each other, and a large cutting sound is generated, a generated noise can be kept low as compared with the chipping work using the chipping machine, but it is difficult to bring the noise generated in the peeling work to an allowable small noise. Moreover, in this mortar peeling method, since wedge-shaped chip pieces are installed on a peripheral edge of the concrete cutter, and the mortar is split and taken by a rotating operation of the wedge-shaped chip pieces involved in the rotation of the concrete cutter, a peeling force of the wedge-shaped chip pieces cannot be concentrated easily on a peeling direction of the mortar, and a large peeling force cannot be transmitted to the mortar and thus, in the case of a firmly constructed mortar, the mortar cannot be peeled smoothly in some cases.

An object of the present invention is to provide a mortar peeling method which can keep a sound generated during a peeling work to an allowable quiet sound and can smoothly peel the mortar off the concrete framework. Another object of the present invention is to provide a mortar peeling method which can complete the peeling work efficiency in a short period of time without giving damage to a concrete framework.

Solution to Problem

A premise of the present invention in order to solve the above described problems is a mortar peeling method using a mortar peeling device for peeling a mortar constructed on a concrete framework.

A feature of the present invention on the above described premise is that the mortar peeling device is composed of a guide member separated away from an outer surface of mortar by a predetermined dimension and extending in one direction in parallel with the outer surface of the mortar, a jack having a piston rod capable of extending forward in one direction and located between the mortar and the guide member, a cutter located at a tip end portion of the piston rod and peeling the mortar off a concrete framework, jack connecting means for connecting the jack to the guide member at a predetermined spot, and first fixing means for fixing the guide member and the jack to a peeling spot of the mortar, and a mortar peeling method performs a mortar peeling process of peeling the mortar having a predetermined thickness off the concrete framework using the cutter by gradually advancing the cutter forward in one direction by gradually extending the piston rod of the jack forward in one direction.

As an example of the present invention, in the mortar peeling method, after the piston rod of the jack is extended forward in one direction, and a mortar is peeled, the piston rod is retreated rearward in one direction so as to complete a session of a mortar peeling process, and in the mortar peeling method, after the first mortar peeling process is executed, a jack movement process of releasing connection between the jack and the guide member and moving the jack forward in one direction is executed, and a subsequent mortar peeling process of connecting the jack to the guide member again after the jack is moved forward in one direction, gradually advancing the cutter forward in one direction by gradually extending the piston rod forward in one direction and peeling the mortar having a predetermined thickness off the concrete framework by using the cutter are executed.

As another example of the present invention, in the mortar peeling method, prior to execution of the first mortar peeling process, a guide groove creating process of creating two guide grooves extending linearly in one direction in the mortar along an outer edge of a peeling width of the mortar is executed, and a cutter installation portion creating process of chipping the mortar at a spot between the guide grooves and of drilling a cutter installation portion where the cutter is to be installed is executed.

As another example of the present invention, the mortar peeling device includes cutter connecting means for detachably connecting the cutter to the tip end portion of the piston rod, and in the mortar peeling method, prior to execution of the first mortar peeling process, a device preparation process of preparing the mortar peeling device by connecting the jack to the guide member at a predetermined spot through the jack connecting means while connecting the cutter to the tip end portion of the piston rod through the cutter connecting means is executed, and a device fixing process of fixing the mortar peeling device to the peeling spot of the mortar in the concrete framework through the first fixing means is executed.

As another example of the present invention, in the mortar peeling method, the movement process and the subsequent mortar peeling process are repeated, and after all the mortar as a peeling target is peeled off the concrete framework, a device removing process of removing the mortar peeling device off the peeling spot of the mortar is executed.

As another example of the present invention, the first fixing means is composed of a first anchor fixed to an anchor hole drilled in the mortar and a pressing plate detachably fixed to a free end portion of the first anchor exposed from the anchor hole and pressing the guide member toward the mortar, and in the mortar peeling method, the first fixing means is attached in the device fixing process, and the first fixing means is removed in the device removing process.

As another example of the present invention, the mortar peeling device includes second fixing means installed on a front end portion of the guide member and preventing movement of the guide member forward in one direction, and the second fixing means is composed of a first front endplate brought into contact with the front end portion of the guide member, a second front end plate connected to the first front end plate and brought into contact with the mortar, and a second anchor inserted into an anchor hole drilled in mortar and fixing the second front end plate to the mortar, and in the mortar peeling method, the second fixing means is attached in the device fixing process, and the second fixing means is removed in the device removing process.

As another example of the present invention, the mortar peeling device includes third fixing means installed on a rear end portion of the guide member and preventing movement rearward in one direction of the guide member, and the third fixing means is composed of a first rear end plate brought into contact with the rear end portion of the guide member, a second rear end plate connected to the first rear end plate and brought into contact with the mortar, and a third anchor inserted into an anchor hole drilled in the mortar and fixing the second rear end plate to the mortar, and in the mortar peeling method, the third fixing means is attached in the device fixing process, and the third fixing means is removed in the device removing process.

As another example of the present invention, the cutter is composed of a cutting edge located at a predetermined depth from an outer surface of the mortar and a mounting base connected to the cutting edge, and in the mortar peeling method, a top portion of the mounting base is slidably brought into contact with the guide member and prevents movement of the cutter in a direction away from the outer surface of the mortar.

As another example of the present invention, in the mortar peeling method, by adjusting a dimension in a direction crossing one direction of a cutting edge, a peeling width of the mortar peeled off the concrete framework can be adjusted.

As another example of the present invention, in the mortar peeling method, a sound pressure level generated in peeling of the mortar is within a range of 50 to 80 dB.

As another example of the present invention, the jack is a hydraulic jack connected to an electric hydraulic jack.

Advantageous Effects of Invention

According to the mortar peeling method according to the present invention, since a mortar peeling process of gradually advancing a cutter forward in one direction by gradually extending a piston rod of a jack forward in one direction and of peeling mortar with a predetermined thickness off a concrete framework by using the cutter is executed, a large cutting sound caused by rubbing between a cutting surface of the mortar and the cutter is not generated, and a sound generated during a peeling work can be kept to an allowable quiet sound while the mortar can be peeled of the concrete framework. Regarding the mortar peeling method, a force (torque) is transmitted linearly from the piston rod of the jack to the cutter, and a linear force of the cutter can be concentrated on a peeling spot of the mortar, whereby a large peeling force acts on the mortar, and thus, even a firmly constructed mortar can be peeled smoothly and reliably. Since the mortar peeling method can smoothly peel the mortar off the concrete framework by using the jack and the cutter, not only that a peeling work can be completed efficiently in a short period of time but also the mortar can be peeled over a wide range once off the concrete framework, and the peeling work can be performed inexpensively. In the mortar peeling method, since unnecessary vibration is not transmitted to the concrete framework during the mortar peeling work, the mortar can be peeled off the concrete framework without damaging the concrete framework. Moreover, the mortar can be peeled off the concrete framework uniformly in a short period of time with high accuracy, generation of fine particles and dusts during the peeling work is less, and the peeling work can be performed in a favorable environment.

In the mortar peeling method in which, after the first mortar peeling process is executed in which the piston rod of the jack is extended forward in one direction, and the mortar is peeled, the piston rod is retreated rearward in one direction so as to complete a session of the mortar peeling process, and after the first mortar peeling process is executed, the movement process of releasing connection between the jack and the guide member and moving the jack forward in one direction is executed, and the subsequent mortar peeling process of connecting the jack to the guide member again after the jack is moved forward in one direction, gradually advancing the cutter forward in one direction by gradually extending the piston rod forward in one direction and peeling the mortar off the concrete framework is executed, after peeling for a portion of the extended dimension of the piston rod is performed, peeling for the portion of the extended dimension of the piston rod can be further performed by moving the jack forward in one direction and connecting the jack to the guide member again, and thus, the mortar peeling process can be executed repeatedly, and even if a peeling length of the mortar is large, all the mortar as the peeling target can be peeled off the concrete framework. Since in the mortar peeling method, the jack is moved forward in one direction and the jack is only connected to the guide member as a work in which the peeling process is repeatedly performed and other works are not involved, the peeling work of the mortar can be completed without labor in a short period of time and with efficiency.

In the mortar peeling method in which, prior to execution of the first mortar peeling process, the guide groove creating process of creating the two guide grooves extending linearly in one direction in the mortar along the outer edge of the peeling width thereof is executed, and the cutter installation portion creating process of chipping the mortar at the spot between the guide grooves and of drilling the cutter installation portion where the cutter is to be installed is executed, since the guide grooves are created on the outer edge of the peeling width of the mortar by the guide groove creating process, and the mortar peeling process is executed by installing the peeling device on inner sides of those guide grooves, only the mortar present in the inner side of the guide grooves can be peeled, the mortar can be partially peeled off the concrete framework, and only the mortar requiring peeling in the entire mortar can be peeled. In the mortar peeling method, since the cutter installation portion with the predetermined depth where the cutter is to be installed is drilled at the spot between the guide grooves by the cutter installation portion creating process, by installing the cutter in the cutter installation portion with the predetermined width and peeling the mortar, the mortar with the predetermined thickness can be reliably peeled off the concrete framework.

In the mortar peeling method in which, prior to execution of the first mortar peeling process, the device preparation process of preparing the mortar peeling device by connecting the jack to the guide member at the predetermined spot through the jack connecting means while connecting the cutter to the tip end portion of the piston rod through the cutter connecting means is executed, and the device fixing process of fixing the mortar peeling device to the peeling spot of the mortar in the concrete framework through the fixing means is executed, the mortar peeling device composed of the cutter, the jack, and the guide member is prepared in advance by the device preparation process, and the mortar peeling device is fixed to the peeling spot of the mortar by the device fixing process and thus, the mortar peeling work can be performed only by fixing the mortar peeling device already prepared to the peeling spot, a construction period required for mortar peeling can be drastically reduced, and the peeling work can be performed inexpensively. In the mortar peeling method, mortar peeling can be performed in any other spots in the concrete framework such as a ceiling, a wall, a floor slab and the like.

In the mortar peeling method in which the movement process and the subsequent mortar peeling process are repeated, and after all the mortar as the peeling target is peeled off the concrete framework, the device removing process of removing the mortar peeling device off the peeling spot of the mortar is executed, after all the mortar as the peeling target is peeled, by removing the peeling device from the concrete framework by the device removing process, only the concrete framework from which the mortar has been peeled can be left, and a renovation work of the mortar, an earthquake strengthening work by increasing a thickness of the mortar and the like after that can be smoothly performed. In the mortar peeling method, the removed mortar device can be used for other spots of the concrete framework and peeling of the mortar in other concrete frameworks, and not only that the mortar can be peeled over a wide range once off the concrete framework but also the mortar peeling can be performed in any other spots in the concrete framework such as a ceiling, a wall, a floor slab and the like.

In the mortar peeling method in which the first fixing means is composed of the first anchor and the pressing plate detachably fixed to the free end portion of the first anchor and pressing the guide member toward the mortar, and the first fixing means is attached in the device fixing process, and the first fixing means is removed in the device removing process, during the work of moving the cutter (piston rod) forward in one direction, a force for moving the guide member in a direction away from the outer surface of a cement cured article acts on the guide member from the cutter, but since the movement of the guide member in the direction away from the outer surface of the mortar is prevented by the first anchor and the pressing plate, the cutter can be made to reliably bite into the mortar, and the mortar with the predetermined thickness can be reliably peeled off the concrete framework. In the mortar peeling method, by removing the first fixing means in the device removing process after all the mortar as the peeling target is peeled, only the concrete framework from which the mortar has been peeled can be left, a renovation work of the mortar, an earthquake strengthening work by increasing a thickness of the mortar after that can be smoothly performed.

In the mortar peeling method in which the second fixing means preventing movement of the guide member forward in one direction is attached in the device fixing process, the second fixing means is attached in the device fixing process, and the second fixing means is removed in the device removing process, during the work of moving the cutter (piston rod) rearward in one direction, a force for moving the guide member forward in the one direction acts on the guide member from the cutter, but since the movement of the guide member forward in one direction is prevented by the second fixing means attached in the device fixing process, shifting of the guide member or the cutter with respect to the concrete framework during the peeling work can be prevented, the cutter can be smoothly retreated rearward in one direction after the mortar peeling process is executed, and the subsequent peeling process can be smoothly executed. In the mortar peeling method, after all the mortar as the peeling target is peeled, by removing the second fixing means in the device removing process, only the concrete framework from which the mortar has been removed can be left, and a renovation work of the mortar, an earthquake strengthening work by increasing a thickness of the mortar and the like after that can be smoothly performed.

In the mortar peeling method in which the third fixing means preventing movement of the guide member rearward in one direction is attached in the device fixing process, and the third fixing means is removed in the device removing process, during the peeling work of moving the cutter (piston rod) forward in one direction, a force for moving the guide member rearward in one direction acts on the guide member from the cutter, but since the movement of the guide member rearward in one direction is prevented by the third fixing means attached in the device fixing process, shifting of the guide member or the cutter with respect to the concrete framework during the peeling work can be prevented, the cutter can be made to reliably bite into the mortar, and the mortar with the predetermined thickness can be reliably peeled off the concrete framework. In the mortar peeling method, after all the mortar as the peeling target is peeled, by removing the third fixing means in the device removing process, only the concrete framework from which the mortar has been peeled can be left, and a renovation work of the mortar, an earthquake strengthening work by increasing a thickness of the mortar after that can be smoothly performed.

In the mortar peeling method, the cutter is composed of the cutting edge located at the predetermined depth from the outer surface of the mortar and the mounting base connected to the cutting edge, and the top portion of the mounting base is slidably brought into contact with the guide member and prevents movement of the cutter in a direction away from the outer surface of the mortar, during the peeling work of moving the cutter (piston rod) forward in one direction, a force for moving the cutter in the direction away from the outer surface of the mortar acts on the cutter, but since the movement of the cutter in the direction away from the outer surface of the mortar is prevented by the guide member fixed by the first fixing means, the cutting edge of the cutter can be made to reliably bite into the mortar, and the mortar with the predetermined thickness can be reliably peeled off the concrete framework.

In the mortar peeling method, by adjusting the dimension in the direction crossing one direction of the cutting edge, the peeling width of the mortar peeled off the concrete framework can be adjusted, by reducing the dimension of the cutting edge of the cutter, the peeling dimension of the mortar to be peeled off the concrete framework can be reduced, and by increasing the dimension of the cutting edge of the cutter, the peeling dimension of the mortar to be peeled off the concrete framework can be increased, and thus, the peeling dimension (peeling area) of the mortar to be peeled off the concrete framework can be handled, and the mortar with a desired peeling dimension can be peeled off the concrete framework.

In the mortar peeling method in which the sound pressure level generated in peeling of mortar is within a range of 50 to 80 dB, since the sound pressure level generated during the peeling is within the above described range, the mortar can be peeled off the concrete framework without generating a large noise, and the sound generated during the peeling work can be kept to an allowable quiet sound. In the mortar peeling method, the mortar peeling work can be performed for the concrete framework in a place requiring a silent environment, a time slot of the peeling work is not limited, and peeling of the mortar can be completed in a short construction period.

In the mortar peeling method in which the jack is a hydraulic jack connected to an electric hydraulic jack, by using a jack operated by a hydraulic pressure as the jack, a large force (torque) can be transmitted from the piston rod to the cutter, and a large peeling force acts on the mortar, and thus, the mortar can be peeled off the concrete framework smoothly and reliably.

MODE FOR CARRYING OUT THE INVENTION

By referring to the attached drawings such asFIG. 1which is a top view of a mortar peeling device10A illustrated as an example and the like, details of a mortar peeling method according to the present invention will be described as follows.FIG. 2is a perspective view of the mortar peeling device10A, andFIG. 3is a side view of the mortar peeling device10A.FIG. 4is a sectional view on an arrow of L-L line inFIG. 1, andFIG. 5is an enlarged perspective view of a cutter14.

InFIG. 1, one direction (longitudinal direction in a building illustrated inFIG. 1) is indicated by an arrow A, while a width direction (vertical direction in the building illustrated inFIG. 1) crossing the one direction is indicated by an arrow B. InFIGS. 1 to 4, a state in which the mortar peeling device10A is installed on an upper part on an inner wall11of the building is illustrated. InFIG. 2, front and rear end portions29and35of a guide member12and first fixing means15are not shown, and inFIGS. 2 and 3, a hydraulic tube43is not shown. InFIG. 5, the guide member12and the piston rod42are indicated by one-dot chain lines.

In the mortar peeling method, mortar21having a predetermined thickness constructed on a concrete framework20of the building is peeled off the concrete framework20by using the mortar peeling device10A or a mortar peeling device10B which will be described later. In the mortar peeling method, each of a device preparation process, a guide groove creating process, a cutter installation portion creating process, an anchor fixing process, a device fixing process, a first peeling process (first mortar peeling process), a jack first movement process (jack movement process), a second peeling process (subsequent mortar peeling process), a jack second movement process (jack movement process), . . . a jack n-th movement process (jack movement process), a n-th peeling process, (subsequent mortar peeling process), a device removing process, and an anchor cutting process is executed. The building includes any type of buildings such as an office building, an intelligent building, an apartment house, a hospital, a school, a nuclear power plant, an indoor parking lot, a basement parking lot and the like and also any type of structures such as a dam, a bridge, a road, an outer wall and the like.

Hereinafter, the mortar peeling method will be described by using a case in which the mortar peeling device10A is installed on the inner wall11of a reinforced concrete building as an example. The mortar peeling device10A can be used not only for the inner wall11of the building but also can be installed on a floor slab, a cantilever slab, a ceiling slab, a column, and a beam of a building and used for peeling of the mortar21constructed on them. In those figures, the mortar peeling device10A is installed in the longitudinal direction in the inner wall11of the building (concrete framework), but an installation direction (direction in which the guide member extends) of the device10A in the inner wall11of the building is not particularly limited, and as long as a space for installing the device10A can be ensured, the device10A can be installed in any direction. The mortar peeling device10A is provided with the guide member12extending in one direction, a hydraulic jack13, the cutter14, first to third fixing means15to17, and first to second connecting means18and19.

The guide member12is a hollow cylindrical metal pipe (an iron pipe, an aluminum pipe, a stainless pipe and the like) extending in one direction, and its sectional shape is molded circularly. The guide member12may be molded not only having a circular shape but also having a square sectional shape. The guide member12is separated away from the outer surface of the mortar21by a predetermined dimension and is installed on the inner wall11of the building so as to be in parallel with the outer surface of the mortar21. It is only necessary that the guide member12has a length dimension of a peeling length or more of the mortar21to be peeled off, and the length dimension is not particularly limited. In the guide member12, a plurality of through holes22(first connecting means18) are drilled therein by penetrating and being juxtaposed at equal intervals (predetermined intervals) in one direction. The guide member12is installed and fixed to the inner wall11by the first to third fixing means15to17.

The first fixing means15are juxtaposed in one direction away from each other by a predetermined dimension in one direction and prevent movement of the guide member12in a direction away from the outer surface of the mortar21. InFIG. 1, two units of the first fixing means15are illustrated, but the number of the fixing means15is not particularly limited and three or more units of the fixing means15may be installed in accordance with the length dimension of the guide member12. The first fixing means15is composed of a first anchor24inserted and fixed into an anchor hole23drilled in the inner wall11(the concrete framework20and the mortar21) and a pressing plate26detachably fixed to a free end portion25of the anchor24exposed from the anchor hole23.

The first anchors24are arranged on both sides of the member12in a state in which the two anchors sandwich the guide member12. As the first anchor24, though not illustrated in detail, any one of a capsule type anchor, a resin injection anchor, a screw anchor, a cut anchor can be used. The first anchor24is made of steel but other than the steel, it may be made of metal such as stainless, an aluminum alloy, a titanium alloy and the like or a synthetic resin.

The pressing plate26is a metal plate elongated in a width direction, and an opening27extending in the width direction is formed at a center part thereof. In the opening27of the pressing plate26, the free end portion25of the first anchor24is removably inserted. A male screw formed on the free end portion25of the first anchor24has a hexagon head nut28screwed. The pressing plate26is pressed by the nut28toward the outer surface of the mortar21, and the pressing plate26is fixed by the first anchor24and the nut28and also, the guide member12is pressed by the pressing plate26toward the outer surface of the mortar21.

The second fixing means16is installed on the front end portion29of the guide member12. The second fixing means16is composed of a first front end plate30brought into contact with the front end portion29of the guide member12, a second front end plate31connected to the first front end plate30and brought into contact with the inner wall11(mortar21), and a second anchor33inserted into an anchor hole32drilled in the inner wall11(the concrete framework20and the mortar21). The first front endplate30and the second front endplate31are made of metal such as iron, aluminum, stainless and the like, and the plates30and31are integrated so as to form an L-shaped stopper.

At a center part of the second front endplate31, a through hole penetrating the plate31is formed. Into the through hole, a free end portion34of the second anchor33exposed from the anchor hole32is removably inserted. With a male screw formed on the free end portion34of the second anchor33exposed from the through hole, a hexagon head nut28is screwed. As the second anchor33, similarly to the first anchor24, any one of a capsule type anchor, a resin injection anchor, a screw anchor, and a cut anchor can be used. The first and second front end plates30and31are fixed to the inner wall11(mortar21) by the second anchor33and the hexagon head nut28, and movement of the guide member12forward in one direction is prevented by the second fixing means16(first front end plate30).

The third fixing means17is installed on a rear end portion35of the guide member12. The third fixing means17is composed of a first rear end plate36brought into contact with the rear end portion35of the guide member12, a second rear endplate37connected to the first rear endplate36and brought into contact with the inner wall11(mortar21), and a third anchor39inserted into an anchor hole38drilled in the inner wall11(the concrete framework20and the mortar21). The first rear end plate36and the second rear end plate37are made of metal such as iron, aluminum, stainless and the like, and the plates36and37are integrated so as to form an L-shaped stopper.

At a center part of the second rear end plate37, a through hole penetrating the plate38is formed. Into the through hole, a free end portion40of the third anchor39exposed from the anchor hole38is removably inserted. With a male screw formed on the free end portion40of the third anchor39exposed from the through hole, the hexagon head nut28is screwed. As the third anchor39, similarly to the first anchor24, any one of a capsule type anchor, a resin injection anchor, a screw anchor, and a cut anchor can be used. The first and second rear end plates36and37are fixed to the inner wall11(mortar21) by the third anchor39and the hexagon head nut28, and movement of the guide member12rearward in one direction is prevented by the third fixing means17(first rear end plate36).

Though not shown, if the front end portion29or the rear end portion35of the guide member12is brought into contact with the outer surface of the column or the beam of the building, the column or the beam is used as the second fixing means16or the third fixing means17, and movement forward in one direction or rearward in one direction of the member12can be prevented by the column or the beam, installation of the second fixing means16(the first front end plate30, the second front end plate31, the second anchor33) or the third fixing means17(the first rear end plate36, the second rear end plate37, the third anchor39) can be omitted.

The hydraulic jack13is located between the guide member12and the mortar21. InFIG. 1, the hydraulic jack13is detachably connected to the rear end portion of the guide member12through the first connecting means18. The hydraulic jack13has a cylindrical hydraulic cylinder41and a columnar piston rod42. On a peripheral wall in a front end portion and an intermediate portion of the hydraulic cylinder41, a hydraulic tube43is attached. The hydraulic tube43is connected to an electric hydraulic pump44. In the hydraulic jack13, the piston rod42is extended (advanced) forward in one direction and also retreated rearward in one direction by a hydraulic oil (hydraulic working oil) fed out of the hydraulic pump44. As the jack, other than the hydraulic jack13, a water-pressure jack can be also used.

The first connecting means18is composed of a slider45connected to a rear end portion of the hydraulic jack13(hydraulic cylinder41), the through hole22drilled in the guide member12, a through hole46drilled in the slider45(a cylinder member48which will be described later), and a connecting pin47removably inserted into each of the through holes22and46. The slider45is made of metal such as iron, aluminum, stainless and the like. The slider45is formed of the cylindrical cylinder member48detachably fitted with the outer peripheral surface of the guide member12and a base49connected to a rear end portion of the cylinder member48. The cylinder member48and the base49are fixed by welding and integrated. The cylinder member48is slidable forward in one direction and rearward in one direction on the outer peripheral surface of the guide member12.

The base49is molded having a prism shape and has both side walls and a bottom wall. Inside the base49, the rear end portion of the hydraulic cylinder41is accommodated, and the rear end portion of the cylinder41is fixed to the base49by welding. The bottom wall (bottom surface) of the base49is brought into contact with the outer surface of the inner wall11(mortar21). The through holes46are formed on a peripheral surface of the cylinder member48, penetrate in a width direction and are juxtaposed in one direction away from each other by a predetermined dimension. The connecting pin47is made of metal such as iron, aluminum, stainless and the like.

The cylinder member48is fitted with the outer peripheral surface of the guide member12, and the through hole22formed in the guide member12is matched with the through hole46formed in the cylinder member48and then, the connecting pin47is inserted through the through holes22and46so that the hydraulic jack13can be connected to the guide member12. On the contrary, by pulling the connecting pin47out of the through holes22and46, the connection between the hydraulic jack13and the guide member12can be released. After the connection between the hydraulic jack13and the guide member12is released, by sliding the slider45forward in one direction or rearward in one direction and by inserting the connecting pin47into those through holes22and46, the jack13can be installed at a predetermined spot of the guide member12.

The cutter14is made of steel, and as illustrated inFIG. 5, it is made of a cutting edge50for peeling off the mortar21and a mounting base51connecting to the cutting edge50. The cutter14is detachably connected to the tip end portion of the piston rod42through the second connecting means19. The second connecting means19is composed of two through holes52drilled in the tip end portion of the piston rod42, two through holes53drilled in the mounting base51of the cutter14, and a connecting pin54to be removably inserted into those through holes52and53.

The connecting pin54is made of metal such as iron, aluminum, stainless and the like. The cutting edge50is located at a predetermined depth from the outer surface of the mortar21and is brought into contact with the outer surface of the concrete framework20. In the cutter14inFIG. 5, the cutting edge50and the mounting base51are integrated, but a blade having the cutting edge50and the mounting base51may be separable so that the blade can be detachably fixed to the mounting base51.

The mounting base51has a top portion55, a bottom portion57, and an intermediate portion56located between the top and bottom portions55and57. The top portion55of the mounting base51is molded having a semicircular shape which is substantially the same as the shape of the outer peripheral surface of the guide member12and is slidably brought into contact with the outer peripheral surface of the guide member12. When the top portion55of the mounting base51is brought into contact with the outer peripheral surface of the guide member12, movement of the cutter14(cutting edge50) in a direction away from the outer surface of the concrete framework20is prevented.

In the intermediate portion56of the mounting base51, an insertion hole58into which the tip end portion of the piston rod42is removably inserted and a contact surface59with which the tip end of the rod42is brought into contact are formed. The insertion hole58penetrates in one direction. The through hole52forming the second connecting means19is formed in the intermediate portion56of the mounting base51and penetrates in a width direction. The bottom portion57of the mounting base51is brought into contact with the outer surface of the mortar21.

When the tip end portion of the piston rod42is inserted into the through hole58of the mounting base51, and the tip end of the rod42is brought into contact with the contact surface59of the mounting base51, the through hole52drilled in the tip end portion of the rod42matches the through hole53drilled in the mounting base51. In a state in which the through holes52and53are matched with each other, the cutter14can be connected to the tip end portion of the piston rod42by inserting the connecting pin54into those through holes52and53.

On the other hand, by pulling the connecting pin54out of the through holes52and53, the connection between the cutter14and the piston rod42can be released. When the piston rod42of the hydraulic jack13extends forward in one direction, the cutter14(cutting edge50) moves forward in one direction with that, while when the piston rod42retreats rearward in one direction, the cutter14moves rearward in one direction with that.

FIG. 6is a diagram illustrating an example of a mortar peeling method using the mortar peeling device10A, andFIG. 7is a diagram illustrating the mortar peeling method continued fromFIG. 6. InFIG. 6, one direction (a longitudinal direction in a building illustrated inFIG. 6) is indicated by an arrow A, and a width direction (vertical direction in the building illustrated inFIG. 6) crossing the one direction is indicated by an arrow B.

The mortar peeling method will be described on the basis of those figures as follows. First, as prior preparation for executing these processes, a peeling spot on the inner wall11where the mortar21is to be peeled is determined, a peeling width dimension of the mortar21(a dimension in a width direction of the mortar21to be peeled) is determined, a peeling length dimension of the mortar21(a dimension in one direction of the mortar21to be peeled) is determined, and a peeling depth dimension of the mortar21(a depth dimension toward the concrete framework20of the mortar21to be peeled) is determined.

Depending on the peeling width dimension of the mortar21, a width dimension of the cutting edge50of the cutter14is determined. Specifically, if the peeling width dimension of the mortar21is large, the cutter14having the cutting edge50with a large width dimension is used, while if the peeling width dimension of the mortar21is small, the cutter14having the cutting edge50with a small width dimension is used. In the mortar peeling method, the peeling width dimension of the mortar21to be peeled off the concrete framework20(peeling dimension in a direction crossing the one direction) can be adjusted by adjusting the width dimension of the cutting edge50(dimension in the direction crossing the one direction).

After those dimensions are determined, the tip end portion of the piston rod42is inserted into the through hole58of the mounting base51, the tip end of the rod42is brought into contact with the contact surface59of the mounting base51, and in the state in which the through holes52and53are matched with each other, the connecting pin54is inserted into those through holes52and53, and the cutter14is connected to the tip end portion of the rod42by the second connecting means19. In the mortar peeling method, the piston rod42and the cutter14can be easily connected through the connecting pin54and moreover, the connection between the rod42and the cutter14can be easily released by pulling out the connecting pin54, and the cutter14(cutting edge50) damaged by a long-term use can be rapidly replaced.

Subsequently, the cylinder member48of the slider45is fitted with the outer peripheral surface of the guide member12, and in the state in which the through holes22and46are matched with each other, the connecting pin47is inserted into those through holes22and46, and the hydraulic jack13is connected to the guide member12by the first connecting means18(device preparation process). In the mortar peeling method, the hydraulic jack13and the guide member12can be easily connected through the slider45and the connecting pin47, and the connection between the jack13and the guide member12can be easily released by pulling out the connecting pin47.

In parallel with the device preparation process or after the mortar peeling device10A is prepared in the device preparation process, as illustrated inFIG. 6, two guide grooves60extending linearly in one direction along an outer edge of a peeling width of the mortar21are formed (guide groove creating process). Specifically, by using a concrete cutter, the mortar21is cut along the outer edge of the peeling width so as to create the guide grooves60. A groove depth of each of the guide grooves60is the same as the peeling depth of the mortar21.

The guide grooves60are made for peeling only the mortar21constructed on the inner side of those guide grooves60and for preventing peeling of the mortar21constructed outside of the guide grooves60. If the mortar21is to be peeled off the whole region of the inner wall11, the creation of the guide grooves60can be omitted. After the guide grooves60are made, the mortar21at a spot between the guide grooves60is peeled, and a cutter installation portion61in which the cutter14is fitted is drilled at the spot (cutter installation portion creating process). Specifically, by using a core drill, the cutter installation portion61having the substantially same length and width as the length dimension and the width dimension of the cutter14is made.

After the guide grooves60are made and the cutter installation portion61is made, the cylindrical anchor holes23,32, and38are drilled at spots where the first to third fixing members15to17are to be installed, and the first to third anchors24,33, and39are installed and fixed in those anchor holes23,32, and38(anchor fixing process). Those anchor holes23,32, and38are drilled by a vibration drill (electric tool) (not shown). The anchor holes23,32, and38penetrate mortar21(mortar layer) and reach the concrete framework20. As long as the first to third anchors24,33, and39can be firmly fixed, the depth dimensions of the anchor holes23,32, and38are not particularly limited.

After the first to third anchors24,33, and39are fixed to each of the anchor holes23,32, and38, the guide member12to which the hydraulic jack14is connected is installed and fixed at the center in the width direction of the guide grooves60through the first to third fixing means15to17(device fixing process). The guide member12is positioned at the center in the width direction of the guide groove60, the cutter14is positioned in the cutter installation portion61, and the bottom wall of the base49of the slider45is brought into contact with the mortar21between the guide grooves60. Subsequently, the free end portion25of the first anchor24is inserted into the opening27of the pressing plate26, and the hexagon head nut28is screwed with the free end portion25so as to firmly fix the pressing plate26by the first anchor24and the nut28.

After the pressing plate26is fixed, the pressing plate26is pressed by the nut28toward the outer surface of the mortar21, the guide member12is pressed by the pressing plate26toward the outer surface of the mortar21, and the member12is fixed by the pressing plate26(fixation by the first fixing means).

During the peeling work in which the cutter14is moved forward in one direction, the force for moving the guide member12in the direction away from the outer surface of the mortar21acts on the guide member12from the cutter14, but since the movement of the guide member12in the direction away from the outer surface of the mortar21is prevented by the first anchor24and the pressing plate26, the cutting edge50of the cutter14can be made to reliably bite into the mortar21.

After the guide member12is fixed by the first fixing means15, the free end portion34of the second anchor33is inserted into the through hole of the second front end plate31, the first front end plate30is brought into contact with the front end portion29(front end) of the guide member12, the free end portion34of the second anchor33exposed from the through hole is screwed with the hexagon head nut28, and the first and second front end plates30and31are fixed to the outer surface of the mortar21by the second anchor33and the hexagon head nut28. The front end portion29of the guide member12is fixed by the first and second front endplates30and31(fixation by the second fixing means).

During the work in which the cutter14(the piston rod42) is moved rearward in one direction, the force for moving the guide member12forward in the one direction acts on the guide member12from the cutter14, but since the movement of the guide member12forward in the one direction is prevented by the first and second front endplates30and31and the second anchor33, shifting movement of the guide member12and the cutter14with respect to the mortar21can be prevented, and the cutter14can be smoothly retreated rearward in one direction after the peeling process has been performed.

After the front end portion29of the guide member12is fixed by the second fixing means16, the free end portion40of the third anchor39is inserted into the through hole of the second rear end plate37, the first rear end plate36is brought into contact with the rear end portion35(rear end) of the guide member12, the free end portion40of the third anchor39exposed from the through hole is screwed with the hexagon head nut28, and the first and second rear end plates36and37are fixed to the outer surface of the mortar21by the third anchor39and the hexagon head nut28. The rear end portion35of the guide member12is fixed by the first and second rear end plates36and37(fixation by the third fixing means).

During the peeling work in which the cutter14(piston rod42) is moved forward in one direction, the force for moving the guide member12rearward in the one direction acts on the guide member12from the cutter14, but since the movement of the guide member12rearward in the one direction is prevented by the first and second rear end plates36and37and the third anchor39, shifting movement of the guide member12and the cutter14with respect to the mortar21during the peeling work can be prevented, and the cutting edge50of the cutter14can be made to reliably bite into the mortar21.

FIG. 8is a diagram illustrating the mortar peeling method continued fromFIG. 7, andFIG. 9is a diagram illustrating the mortar peeling method continued fromFIG. 8.FIG. 10is a diagram illustrating the mortar peeling method continued fromFIG. 9. After the device fixing process is completed, the first peeling process (first mortar peeling process) is executed. In the first peeling process, the electric hydraulic pump44is switched on, the hydraulic jack13is operated by a remote controller, not shown, and the piston rod42of the jack13is extended (advanced) forward in one direction indicated by an arrow A1inFIG. 8. By extending the piston rod42forward in one direction, the cutter14is gradually advanced forward in one direction, and the cutting edge50of the cutter14gradually peels the mortar21with the predetermined thickness off the concrete framework20(first peeling process).

After the piston rod42of the hydraulic jack13is extended to the maximum forward in one direction and the mortar21is peeled for a portion by which the rod42is extended, the hydraulic jack13is operated by the remote controller, and the piston rod42of the jack13is retreated rearward in one direction indicated by an arrow A2inFIG. 8. By retreating the rod42, the first peeling process (one session of the peeling process) is completed. A sound pressure level generated during the peeling of the mortar21is within a range of 50 to 80 dB. The sound pressure level is a value measured by a noise meter separated away from the mortar peeling device10A by 1.2 m. In the mortar peeling method using the mortar peeling device10A, the cutting edge50of the cutter14advances forward in one direction, and the cutting edge50acts to peel the mortar21off, and thus, the cutting surface of the mortar21and the cutter14(cutting edge50) do not rub each other, and a large cutting sound is not generated.

After the first peeling process is completed, the connecting pin47is pulled out of the through holes22and46so as to release the connection between the guide member12and the hydraulic jack13. After the connection between the guide member12and the hydraulic jack13is released, the cylinder member48of the slider45is moved forward in one direction indicated by the arrow A1inFIG. 9on the outer peripheral surface of the guide member12, and the hydraulic jack13is moved forward in one direction (jack first movement process). A maximum moving distance of the jack13forward in one direction is a distance until the cutting edge50of the cutter14is brought into contact with the mortar21to be peeled off the next time.

After the hydraulic jack13is moved forward in one direction, in the state in which the through holes22and46are matched with each other, the connecting pin47is inserted into those through holes22and46again so as to connect the hydraulic jack13to the guide member12again, and the second peeling process is performed. In the second peeling process, the electric hydraulic pump44is switched on, the hydraulic jack13is operated by the remote controller, and the piston rod42of the jack13is extended (advanced) forward in one direction indicated by the arrow A1inFIG. 10.

By extending the piston rod42forward in one direction, the cutter14is gradually advanced forward in one direction, and the cutting edge50of the cutter14gradually peels the mortar21with the predetermined thickness off the concrete framework20(the second peeling process (subsequent mortar peeling process). After the piston rod42of the hydraulic jack13is extended to the maximum forward one direction, and the mortar21is peeled for a portion by which the rod42is extended, the hydraulic jack13is operated by the remote controller, and the piston rod42of the jack13is retreated rearward in one direction indicated by an arrow A2inFIG. 10. By retreating the rod42, the second peeling process (the subsequent session of the peeling process) is completed.

After the second peeling process is completed, the connecting pin47is pulled out of the through holes22and46so as to release the connection between the guide member12and the hydraulic jack13. After the connection between the guide member12and the hydraulic jack13is released, the cylinder member48of the slider45is moved forward in one direction on the outer peripheral surface of the guide member12, and the hydraulic jack13is moved forward in one direction (jack second movement process). After the hydraulic jack13is moved forward in one direction, the peeling work of the mortar21is performed again with the above described procedure. The jack movement process and the mortar peeling process are repeated in accordance with the peeling length of the mortar21(the jack n-th movement process, the mortar n-th peeling process (subsequent mortar peeling process)), and when all the mortar21to be peeled off is peeled, the jack movement process and the mortar peeling process are completed.

After the jack movement process and the mortar peeling process are completed, the device removing process is performed. The hexagon head nut28screwed with the free end portion25of the first anchor24is removed from the free end portion25, fixation of the pressing plate26by the first anchor24and the nut28is released, the pressing plate26is pulled out of the free end portion25of the first anchor24, and the fixation of the guide member12by the pressing plate26is released (release of the fixation by the first fixing means).

Subsequently, the hexagon head nut28screwed with the free end portion34of the second anchor33is removed from the free end portion34, fixation on the mortar21of the first and second front end plates30and31by the second anchor33and the hexagon head nut28is released, and the fixation of the front end portion29of the guide member12by the first and second front end plates30and31(release of the fixation by the second fixing means).

Moreover, the hexagon head nut28screwed with the free end portion40of the third anchor39is removed from the free end portion40, the fixation on the mortar21of the first and second rear endplates36and37by the third anchor39and the hexagon head nut28is released, and the fixation of the rear end portion35of the guide member12by the first and second rear endplates36and37is released (release of the fixation by the third fixing means). After the fixation by the first to third fixing means15to17is released, the guide member12is lowered from the inner wall11, and the mortar peeling device10A is removed from the peeling spot (device removing process).

After the device removing process is completed, the anchor cutting process is performed. In the anchor cutting process, the free end portions25,34, and40of the first to third anchors24,33, and39exposed from the anchor holes23,32, and38are cut by using the cutter. By completing each of the above described processes, the peeling work of the mortar21is completed. If the peeling work is completed in the first session of the peeling process, the device removing process is performed immediately after the first peeling process is completed.

In the mortar peeling method using the mortar peeling device10A, the mortar peeling process is executed by gradually extending the piston rod42of the hydraulic jack13forward in one direction, the cutting edge50of the cutter14is gradually advanced forward in one direction so that the mortar21with the predetermined thickness is peeled off the concrete framework20by using the cutting edge50, a large cutting sound caused by rubbing between the cutting surface of the mortar21and the cutter14(cutting edge50) is not generated, and a sound generated during the peeling work can be kept to an allowable quiet sound (sound with a sound pressure level of 50 to 80 dB) while the mortar21can be peeled off the concrete framework20.

In the mortar peeling method, the force (torque) is linearly transmitted from the piston rod42of the hydraulic jack13to the cutting edge50of the cutter14, the linear force of the cutting edge50can be concentrated on the peeling spot of the mortar21, whereby a large peeling force acts on the mortar21, and thus, even if the peeling width, the peeling length or the peeling depth of the mortar21to be peeled off is large and the mortar21is firmly constructed, the mortar21can be peeled off smoothly and reliably.

In the mortar peeling method, since the mortar21can be smoothly peeled off the concrete framework20by using the hydraulic jack13and the cutter14, not only that the peeling work can be completed efficiently in a short period of time (short construction period) but also the mortar21can be peeled off the concrete framework20over a wide range once, and the peeling work can be performed inexpensively.

In the mortar peeling method, since unnecessary vibration is not transmitted to the concrete framework20during the peeling work of the mortar21, the mortar21can be peeled off without damaging the concrete framework20. Moreover, the mortar21can be peeled off the concrete framework20uniformly in a short period of time with high accuracy, generation of fine particles and dusts during the peeling work is less, and the peeling work can be performed in a favorable environment.

In the mortar peeling method, after the peeling for a portion of the maximum extended dimension of the piston rod42has been performed, the removed hydraulic jack13can be moved forward in one direction and connected to the guide member12again, and the peeling for the portion of the maximum extended dimension of the piston rod42can be performed and thus, the mortar peeling process can be performed repeatedly, and all the mortar21can be peeled off the concrete framework20even if the peeling length of the mortar21in the inner wall11is long. In the mortar peeling method, the hydraulic jack13is simply moved forward in one direction and the jack13is connected to the guide member12as the work for performing the mortar peeling process repeatedly and other works are not involved and thus, the peeling work of the mortar21can be completed without labor in a short period of time and with efficiency.

FIG. 11is a top view of a mortar peeling device10B illustrated as another example, andFIG. 12is a perspective view of the mortar peeling device10B inFIG. 11.FIG. 13is a side view of the mortar peeling device10B inFIG. 11, andFIG. 14is a sectional view on an arrow of M-M line inFIG. 11. InFIG. 11, one direction (vertical direction in a building illustrated inFIG. 11) is indicated by the arrow A, and a direction (transverse direction in the building illustrated inFIG. 11) crossing the one direction is indicated by the arrow B. InFIGS. 11 and 12, the mortar peeling device10B is illustrated in a state installed on the inner wall11. InFIG. 12, the first fixing means15and the front end portion29of the guide member12are not shown.

This mortar peeling device10B is used for peeling of the mortar21constructed on the outer surface of the concrete framework20on the inner wall11of the reinforced concrete building. The mortar peeling device10B is provided with two guide members12extending in one direction, two hydraulic jacks13, two cutters14, first to second fixing means15and16, and first to second connecting means18and19.

Those guide members12are juxtaposed in parallel away from each other in a lateral direction. Each of the guide members12is a hollow cylindrical metal pipe (iron pipe, aluminum pipe, stainless pipe and the like) extending in one direction, similarly to that inFIG. 1, and a sectional shape thereof is molded circularly. The guide members12are separated away from the outer surface of the mortar21by a predetermined dimension and are installed on the inner wall11of the building so as to be in parallel with the outer surface of the mortar21. The guide member12has a length dimension equal to or longer than the peeling length of the mortar21to be peeled. In those guide members12, a plurality of the through holes22(first connecting means18) penetrating the same and juxtaposed at equal intervals (separated away by the predetermined dimension) in one direction are drilled. The guide member12is installed and fixed on the inner wall11by the first and second fixing means15and16.

The first fixing means15are juxtaposed in one direction away from each other by a predetermined dimension and prevent movement of the guide member12in a direction away from the outer surface of the mortar21. The first fixing means15is composed of the first anchor24inserted and fixed to the anchor hole23drilled in the inner wall11and the pressing plate26detachably fixed to the free end portion25of the anchor24exposed from the anchor hole23. The single first anchor24is arranged between the guide members12.

The pressing plate26is the same as that used for the peeling device10A inFIG. 1, and the free end portion25of the first anchor24is inserted into its opening27. A male screw formed on the free end portion25of the first anchor24is screwed with the hexagon head nut28. The pressing plate26is pressed by the nut28toward the outer surface of the mortar21, and the pressing plate26is fixed by the first anchor24and the nut28, and those guide members12are pressed by the pressing plate26toward the outer surface of the mortar21.

The second fixing means16is installed on the front end portion29of the guide member12and prevents movement of the guide member12forward in one direction. The second fixing means16is composed of the first front end plate30brought into contact with the front end portion29of the guide member12, the second front end plate31connected to the first front end plate30and brought into contact with the inner wall11(mortar21), and the second anchor33inserted into the anchor hole32drilled in the inner wall11(the concrete framework20and the mortar21). The first and second front end plates30and31are the same, as those used for the peeling device10A, and the free end portion34of the second anchor33is inserted into the through hole of the second front end plate31.

The male screw formed on the free end portion34of the second anchor33is screwed with the hexagon head nut28. The first and second front end plates30and31are fixed to the inner wall11by the second anchor33and the hexagon head nut28. The rear end portion35(rear end) of the guide member12is brought into contact with a floor slab, and since movement of the guide member12rearward in one direction is prevented by the floor slab, unlike the peeling device10A inFIG. 1, installation of the third fixing means17is omitted.

Those hydraulic jacks13are located between the guide members12and the mortar21and detachably connected to the rear end portion of the guide members12through the first connecting means18. Since the hydraulic jack13is the same as that used for the peeling device10A inFIG. 1, the explanation will be omitted. The first connecting means18is composed of the slider45connected to the rear end portion of the hydraulic cylinder41, the through hole22drilled in the guide member12, the through hole46drilled in the slider45, and the connecting pin47.

The slider45is composed of the cylindrical cylinder member48detachably fitted with the outer peripheral surface of the guide member12and the base49connected to the rear end portion of the cylinder member48. The cylinder member48is slidable forward in one direction and rearward in one direction on the outer peripheral surface of the guide member12. Inside of the base49, the rear end portion of the hydraulic cylinder41is accommodated, and the rear end portion of the cylinder41is fixed to the base49by welding. The bottom wall of the base49is brought into contact with the outer surface of the mortar21.

After the cylinder member48of the slider45is fitted with the outer peripheral surface of the guide member12, and the through holes22and46are matched with each other, by inserting the connecting pin47into those through holes22and46, the hydraulic jack13can be connected to the guide member12. On the contrary, by pulling the connecting pin47out of the through holes22and46, the connection between the hydraulic jack13and the guide member12can be released. After the connection between the hydraulic jack13and the guide member12is released, by sliding the slider45forward in one direction or rearward in one direction and by inserting the connecting pin47into those through holes22and46, the hydraulic jack13can be installed at a predetermined spot of the guide member12.

The cutter14is composed of the cutting edge50and the mounting base51and is detachably connected to the tip end portion of the piston rod42through the second connecting means19(seeFIG. 5). The second connecting means19is composed of the two through holes52drilled in the tip end portion of the piston rod42, the two through holes53drilled in the mounting base51of the cutter14, and the connecting pin54. The cutting edge50is located at a predetermined depth from the outer surface of the mortar21and is brought into contact with the outer surface of the concrete framework20.

The top portion55of the mounting base51is slidably brought into contact with the outer peripheral surface of the guide member12, whereby movement of the cutting edge50in a direction away from the outer surface of the concrete framework20is prevented. In the intermediate portion56of the mounting base51, the insertion hole58into which the tip end portion of the piston rod42is removably inserted and the contact surface59with which the tip end of the rod42is brought into contact are formed. The bottom portion59of the mounting base51is brought into contact with the outer surface of the mortar21.

In a state in which the tip end portion of the piston rod42is inserted into the insertion hole58of the mounting base51, the tip end of the rod42is brought into contact with the contact surface59of the mounting base51, and the through holes52and53are matched with each other, by inserting the connecting pin54into those through holes52and53, the cutter14can be connected to the tip end portion of the piston rod42. On the contrary, by pulling the connecting pin54out of those thorough holes52and53, the connection between the cutter14and the piston rod42can be released. When the piston rod42of the hydraulic jack13is extended forward in one direction, the cutter14(cutting edge50) moves forward in one direction with that, while, when the rod42is retreated rearward in one direction, the cutter14moves rearward in one direction with that.

FIG. 15is a diagram illustrating an example of the mortar peeling method of the mortar21using the mortar peeling device10B, andFIG. 16is a diagram illustrating the mortar peeling method continued fromFIG. 15.FIG. 17is a diagram illustrating the mortar peeling method continued fromFIG. 16, andFIG. 18is a diagram illustrating the mortar peeling method continued fromFIG. 17. InFIG. 15, one direction (vertical direction in a building illustrated inFIG. 15) is indicated by the arrow A, and a direction crossing the one direction (transverse direction in the building illustrated inFIG. 15) is indicated by the arrow B. The mortar peeling method will be described on the basis of those figures as follows. Similarly to the mortar peeling method using the mortar peeling device10A inFIG. 1, a peeling spot on the inner wall11where the mortar21is to be peeled is determined in advance, a peeling width dimension of the mortar21is determined, a peeling length dimension of the mortar21is determined, and a peeling depth dimension of the mortar21is determined.

After those dimensions are determined, the device installation process of installing those mortar peeling devices10B at the peeling spots of the mortar21is performed. The tip end portion of the piton rod42is inserted into the insertion hole58of the mounting base51, the tip end of the rod42is brought into contact with the contact surface59of the mounting base51, and in a state in which the through holes52and53are matched with each other, the connecting pin54is inserted into those through holes52and53, and the tip end portion of the rod42is connected to the cutter14by the second connecting means19. The cylinder member48of the slider45is fitted with the outer peripheral surface of the guide member12, and in a state in which the through holes22and46are matched with each other, the connecting pin47is inserted into those through holes22and46, and the hydraulic jack13is connected to the guide member12by the first connecting means18(device preparation process).

In parallel with the device preparation process or after the mortar peeling device10A is prepared in the device preparation process, as illustrated inFIG. 15, the two guide grooves60extending linearly in one direction along the outer edge of the peeling width of the mortar21are formed (guide groove creating process). After the guide grooves60are created, by using a core drill, the mortar21at a spot between the guide grooves60is peeled off, and the cutter installation portions61in which the cutters14are fitted are drilled at the spot (cutter installation portion creating process). After the guide grooves60are created, and the cutter installation portions61are created, the cylindrical anchor holes22and32are drilled at spots where the first and second fixing members15and16are to be installed, and the first and second anchors24and33are installed and fixed to those anchor holes22and32(anchor fixing process).

After the anchors24and33are fixed to the anchor holes23and32, respectively, those guide members12to which the hydraulic jacks14are connected are installed and fixed at the center in the lateral direction of the guide groove60through the first and second fixing means15and16(device fixing process). Those guide members12are positioned at the center in the lateral direction of the guide groove60, the cutter14is positioned in the cutter installation portion61, and the bottom wall of the base49of the slider45is brought into contact with the mortar21between the guide grooves60.

Subsequently, the free end portion25of the first anchor24is inserted into the opening27of the pressing plate26, the hexagon head nut28is screwed with the free end portion25, and the pressing plate26is firmly fixed by the first anchor24and the nut28. When the pressing plate26is fixed, the pressing plate26is pressed by the nut28toward the outer surface of the mortar21, and the guide member12is pressed by the pressing plate26toward the outer surface of the mortar21, and the member12is fixed by the pressing plate26(fixation by the first fixing means).

After the guide member12is fixed by the first fixing means15, the free end portion34of the second anchor33is inserted into the through hole of the second front end plate31, the first front end plate30is brought into contact with the front end portion29(front end) of the guide member12, the hexagon head nut28is screwed with the free end portion34of the second anchor33exposed from the through hole, and the first and second front end plates30and31are fixed to the outer surface of the mortar21by the second anchor33and the hexagon head nut28. The front end portion29of the guide member12is fixed by the first and second front endplates30and31(fixation by the second fixing means). In the state inFIG. 16in which the guide members12to which the hydraulic jacks13are connected are fixed to the inner wall11, the cutting edges50of the cutters14connected to those jacks13are juxtaposed in the lateral direction.

After the device fixing process is completed, the electric hydraulic pump44is switched on, those hydraulic jacks13are operated by the remote controller, and the piston rods42of the jacks13are extended (advanced) forward in one direction indicated by the arrow A1inFIG. 16. As a result, those cutters14are gradually advanced forward in one direction in synchronization, each of the cutting edges50of the cutters14gradually peels the mortar21with the predetermined thickness off the concrete framework20(first peeling process, first mortar peeling process).

While the piston rods42of those hydraulic jacks13are extended to the maximum forward in one direction in synchronization, and after the mortar21is peeled for a portion by which the rods42are extended, the rods42of the jacks13are retreated in synchronization rearward in one direction indicated by the arrow A2inFIG. 16. By retreating those piston rods42, the first peeling process (a session of the peeling process) is completed. The sound pressure level generated during the peeling of the mortar21is within a range of 50 to 80 dB. The sound pressure level is a value measured by a noise meter separated away from the mortar peeling device10B by 1.2 m. In the mortar peeling method using the mortar peeling device10B, since the cutting edges50of those cutters14linearly advance forward in one direction in synchronization and act so that the cutting edges50peel the mortar21off, the cutting surface of the mortar21is not rubbed with the cutter14(cutting edge50), and a large cutting sound is not generated.

After the first peeling process is completed, the connecting pin47is pulled out of the through holes22and46, the connection between the guide member12and the hydraulic jack13is released, the cylinder member48of the slider45is moved forward in one direction indicated by the arrow A1inFIG. 17on the outer peripheral surface of the guide member12, and the hydraulic jack13is moved forward in one direction (jack first movement process). After the hydraulic jack13is moved forward in one direction, the connecting pin47is inserted into the through holes22and46again so as to connect the hydraulic jack13to the guide member12again, the jack13is operated by the remote controller, and the piston rods42of those jacks13are extended (advanced) forward in one direction indicated by the arrow inFIG. 18.

At this time, similarly to the first peeling process, those piston rods42are operated in synchronization, and in the state in which the cutting edges50of the cutters14are aligned in the lateral direction, the cutters14extend (advance) forward in one direction at the same speed. As a result, those cutters14gradually advance forward in one direction in synchronization, and each of the cutting edges50of the cutters14gradually peels the mortar21with the predetermined thickness off the concrete framework20(second peeling process (subsequent mortar peeling process)).

After the piston rods42of the hydraulic jacks13are extended to the maximum forward in one direction, and the mortar21is peeled for the portion by which the rods42are extended, the hydraulic jacks13are operated by the remote controller and the rods42of the jacks13are retreated rearward in one direction indicated by the arrow A2inFIG. 18in synchronization. By retreating those rods42, the second peeling process (a subsequent session of the peeling process) is completed.

After the second peeling process is completed, the connecting pin47is pulled out of the through holes23and46, the connection between those guide members12and those hydraulic jacks13is released, the cylinder member48of the slider45is moved forward in one direction on the outer peripheral surface of the guide member12, and the hydraulic jack13is moved forward in one direction (jack second movement process). After those hydraulic jacks13are moved forward in one direction, the peeling work of the mortar21is performed again with the above described procedure. The movement process and the peeling process are repeated in accordance with the peeling length of the mortar21(the jack n-th movement process, the mortar n-th peeling process (subsequent mortar peeling process)), and when all the mortar21to be peeled off is peeled, the jack movement process and the mortar peeling process are completed.

After the jack movement process and the mortar peeling process are completed, the hexagon head nut28screwed with the free end portion25of the first anchor24is removed, fixation of the pressing plate26by the first anchor24and the nut28is released, and the pressing plate26is pulled out of the free end portion25of the first anchor24so as to release fixation of the guide member12by the pressing plate26(release of the fixation by the first fixing means).

Subsequently, the hexagon head nut28screwed with the free end portion34of the second anchor33is removed, the fixation of the first and second front end plates30and31to the mortar21by the second anchor33and the hexagon head nut28is released, and the fixation of the front end portion29of the guide member12by the first and second front end plates30and31is released (release of the fixation by the second fixing means). After the fixation by the first and second fixing means15and16is released, the guide member12is lowered from the inner wall11, and the mortar peeling device10B is removed from the peeling spot (device removing process).

After the device removing process is completed, the anchor cutting process is performed. In the anchor cutting process, the free end portions25and34of the first to third anchors24and33exposed from the anchor holes23and32are cut by using the cutter. By completing each of the above described processes, the peeling work of the mortar21is completed. If the peeling work is completed in the first session of the peeling process, the device removing process is performed immediately after the first peeling process is completed.

In the mortar peeling method using the mortar peeling device10B, by gradually extending the piston rods42of those hydraulic jacks13forward in one direction in synchronization, each of the cutting edges50of the cutters14is gradually advanced forward in one direction, and the mortar peeling process for peeling the mortar21with the predetermined thickness off the concrete framework20is executed by using those cutting edges50, and thus, a large cutting sound caused by rubbing between the cutting surface of the mortar21and the cutter14(cutting edge50) is not generated, and the mortar21can be peeled off the concrete framework20while a sound generated during the peeling work is kept to an allowable quiet sound.

In the mortar peeling method, the force (torque) is linearly transmitted from the piston rods42of those hydraulic jacks13to each of the cutting edges50of the cutters14, the linear force of those cutting edges50can be concentrated on the peeling spot of the mortar21by which the large peeling force acts on the mortar21, and thus, even if the mortar21to be peeled has large peeling width, peeling length or peeling depth and is constructed firmly, the mortar21can be peeled off smoothly and reliably.

In the mortar peeling method, since the cutting edges50of the cutters14installed on the guide members12, respectively, are advanced forward in one direction in synchronization, the linear force of the cutting edges50is uniformly transmitted from those cutting edges50to the mortar21, the mortar21can be peeled once over a range which is wide in the lateral direction, and a large quantity of the mortar21can be peeled off in one session of the peeling work.

In the mortar peeling method, since the mortar21can be peeled smoothly off the concrete framework20by using the hydraulic jacks13and the cutters14, not only that the peeling work can be completed efficiently in a short period of time (short construction period) but also the mortar21can be peeled off the concrete framework20over a wide range at once, and the peeling work can be performed inexpensively.

In the mortar peeling method, since unnecessary vibration is not transmitted to the concrete framework20during the peeling work of the mortar21, the mortar21can be peeled without damaging the concrete framework20. Moreover, a large area of the mortar21can be peeled off the concrete framework20uniformly in a short period of time with high accuracy, generation of fine particles and dusts during the peeling work is less, and the peeling work can be performed in a favorable environment.

In the mortar peeling method, after peeling for a portion of the maximum extended dimension of those piston rods42is performed, those removed hydraulic jacks13are moved forward in one direction and connected to the guide members12again and peeling for the portion of the maximum extended dimension of the piston rod42can be further performed, and thus, the mortar peeling process can be performed repeatedly, and even if the peeling length of the mortar21in the inner wall11is large, all the mortar21can be peeled off the concrete framework20. In the mortar peeling method, it is only necessary to move those hydraulic jacks13forward in one direction and to connect them to the guide members12as the work of repeatedly performing the mortar peeling process, and no other work is involved and thus, the peeling work of the mortar21can be completed efficiently without labor in a short period of time.

REFERENCE SIGNS LIST