Drainage system for use with paved road

Abstract: The drainage system includes a base layer (2), a first layer (3) laid on the base layer, a second layer (6) laid on the first layer, a pair of gutters (8) longitudinally provided on both sides of the road, a first braided pipe (10) fabricated by weaving together a predetermined number of warps (11) and a lot of woofs (12) made of heat resistant synthetic fiber, the braided pipe being disposed along the gutter (8) and the downstream-side end of the top surface of the first layer (5), the drainage channel being communicated to catch basins (9) located at the gutter.

Description: BACKGROUND OF THE INVENTION Field of the invention The present invention relates to a drainage system for use with a paved surface such as a road and, more particularly, to a drainage system for draining rainwater penetrating to the base course through an asphalt layer on a road surface. Further, the present invention relates to a drainage system for use with a paved road and, more particularly, to a drainage system which prevents problems such as a drop in slip resistance, a hydroplaning phenomenon, and splashing and spray of water resulting from water floating or remaining on a road surface. Related art Conventionally, curbs or gutters are provided along both sides of a road, and the road is commonly surfaced with a pavement graded toward the center or the sides of the road. In the "GUIDELINES FOR ASPHALT PAVEMENT" edited by the Japan Road Association, descriptions relating to drainage only mention inflow ports formed in the aide of the gutter facing the pavement with regard to surface drainage, sub-surface drainage, and permeable asphalt pavement (Paragraph 2-7-2 "Surface Drainage" on page 38 in the Guidelines For Asphalt Pavement). However, especially in the case of an asphalt pavement, the pavement contains minute pores, and rainwater penetrates through these minute pores during rainfall. If the rainwater having thus penetrated through the pores remains in the asphalt pavement, the aggregate will come away from the asphalt mixture that forms the asphalt pavement, thereby resulting in the fracturing of the pavement. In many cases, maintenance and repair of the road are carried out by cutting the surface of the asphalt pavement and laying a new asphalt mixture over the base course. Rapid drainage of the rainwater penetrating to the inside of the pavement in a simple manner has been desired. In the case of the permeable asphalt pavement, the boring of the inflow port in the side of a U-shaped gutter facing the road involves a lot of labor. Thus, the boring of the inflow port in the gutter is impractical. Further, in the case of an L-shaped gutter, rainwater remaining in the pavement may cause problems. Particularly, road traffic hazards due to water remaining on the road surface become a major problem on highways. The highway is surfaced with a permeable asphalt pavement in order to ensure driving safety and reduce noise. However, this pavement is designed to permit the rainwater to penetrate through to the inside of the porous pavement so as to prevent a water slick on the road surface. The rainwater passes through voids in the pavement, and the thus penetrating rainwater is drained along the top surface of the base course. However, if the voids of the pavement are filled with mud and dirt, that is, if the voids are clogged, the drainage and noise-reduction capability are impaired. The mud and dirt in the voids are conventionally removed by squirting pressurized water onto the road surface and sucking the mud and dirt that float to the road surface from the inside of the pavement. The installation of drains and their improved draining capability may permit the flushing of the mud and dirt. However, it is unlikely that these are sufficient means for maintaining the drainage capability of the pavement. Further, in the case of a road with multiple traffic lanes, the distance of the road from which water has to be drained is increased. In the event of heavy rain, the volume of rainwater may exceed the limit of the draining capacity of the pavement, as a result of which excess surface water arises. The draining capacity of the permeable asphalt pavement depends on the porosity of the pavement. It is evident that a grater porosity leads to better water permeability which, in turn, results in improved permiability, However, the porosity of the pavement must be to the 20% range in order to ensure the strength of the pavement. In the case of a pavement on the surface of a bridge, an asphalt pavement is laid over the surface of a steel base or a reinforce concrete base. Rainwater, or the like, penetrates to the steel base or the reinforced concrete base through the asphalt pavement, so that steel or reinforcements in the base are eroded. The steel base or the reinforced concrete base has a small thickness, and it is directly subject to a wheel load via the asphalt pavement. If the base is repeatedly subjected to the wheel load while it remains in a wet state as a result of the penetrated rainwater, the load capacity of the base will significantly decrease. The "Road Bridge Instructions" issued from the Ministry of Construction require that a waterproof layer be laid on the base. However, an asphalt mixture laid on the waterproof layer contains uneven voids. Further, as a result of deflection load of the base due to repeated wheel loads, minute cracks and the spread of voids develop unevenly in the asphalt mixture on the waterproof layer laid on the base. Furthermore, it is impossible to prevent the rainwater from penetrating through the asphalt pavement along the boundary between the pavement and wheel guards, curbs, or catch basins disposed along both sides of the base. For these reasons, the rainwater remaining in the asphalt pavement as a result of penetration causes the pavement to deteriorate. To immediately drain the rainwater remaining inside the asphalt pavement to the outside, conduits are provided on both sides of the road in its longitudinal direction along the waterproof layer or a joint mixture raised straight up along the wheel guard, the curb, or the catch basin while they are in contact with an upper part of the waterproof layer. The ends of the conduits are connected to outlets opened in the wall surface of an expansion joint or the side surface of the catch basin facing the pavement, whereby the rainwater remaining in the pavement is immediately drained to the outside of the bridge. The outlet is covered with a wire mesh having high corrosion resistance in order to prevent the outlet from being clogged with the aggregate. In this respect, conduits having sufficient voids which guide only the rainwater while preventing the inflow of the aggregate without the use of the wire mesh have already been put forth. For example, a drain structure having such a conduit is disclosed in Unexamined Japanese Patent Publication Hei-6-26013. The drain structure disclosed in this patent publication comprises a waterproof layer which is laid on the base of the bridge and is raised straight up at both ends thereof along the wheel guards disposed on both sides of the bridge base, and an infiltrated water guide member consisting of a spirally coiled stainless steel which is laid along the inner side surface of the corner of the raised portion of the waterproof layer. The infiltrated water guide member consisting of the spiral coil is connected at given points thereof to a drainage system. A pavement material is laid on the waterproof layer and the infiltrated water guide members. The infiltrated water guide member acting as a drainage channel, as disclosed in the above patent publication, is made of a spiral stainless steel coil. This infiltrated water guide member has a lot of problems such as the difficulty in laying it, reflection cracks, cost effectiveness, and problems arising when the infiltrated water guide member has to be cut for repair. A further prior art that is of interest is DE-A-3 619 785 that discloses a drainage system for roads having an upper layer of porous asphalt. Under this layer of asphalt, at each side of the road, is a channel extending in the direction of the road and close to the kerbstones of the road. Each channel has an upper grating and over this grating there may extend a porous mat that is covered by said porous asphalt. At spaced apart locations there are catch basins that receive water from said channels. Under the porous asphalt there may also be further channels extending cross-wise relative to the direction of the road for leading rainwater into said catch basins. These further channels may be covered by a porous mat, all of which is below the porous asphalt. SUMMARY OF THE INVENTION The present invention is conceived in view of the previously mentioned drawbacks in the conventional art, and its object is to provide a drainage system for use with a paved road which uses a drainage channel comprising braided pipes formed from synthetic fiber, being capable of easily draining rainwater when it is laid on the base course on the sub-base of a road, and possessing sufficient strength to support an asphalt pavement. Another object of the present invention is to provide a drainage system for use with a paved road, specifically, a multi-lane road, which is capable of providing a superior drainage efficiency and of preventing surface water even if there is provided the insufficient drainage capability lead by the porosity of the pavement, a hydraulic gradient, and a drainage capability of a road area. The invention is as defined in the accompanying claims. To solve the above objectives, according to one aspect of the present invention there is provided a drainage system for use with a paved road comprising a base layer; a first layer laid on said base layer; a second layer laid on said first layer; a pair of gutters longitudinally provided one on each side of said road; a first braided pipe fabricated by weaving together a predetermined number of warps and a lot of woofs made of heat resistant synthetic fiber, said braided pipe being disposed along the gutter and the downstream-side end of the top surface of said first layer; the first braided pipe being communicated to the gutter at locations where the gutter is formed with catch basins. The base layer may have its top graded. The said first braided pipe of the above drainage system may be sheathed with a non-woven fabric. The above defined drainage system may further comprise a second braided pipe fabricated by weaving together a predetermined number of warps and a lot of woofs made of heat resistant synthetic fiber, said second braided pipe being disposed on said first layer at an angle of substantially 45 degrees with respect said gutters, said second braided pipe being connected said first braided pipe. Said second braided pipe may be fitted into a slot formed in said second layer. Alternatively said second braided pipe may be fitted into a slot formed in said first layer, said slot in the first layer facing said second layer. The braided pipe or pipes may have a diameter of 3 to 35 mm. The heat resistant synthetic fiber may be selected from the group consisting of Polyester, alamide resin and polyamide with a thread size set to 167-3889 tex (1500 to 35,000 deniers). To solve the above objectives, according to a further aspect of the present invention, there is provided a method for producing a drainage system for use with a paved road comprising the steps of: forming a base layer; forming a first layer on said base layer; providing a pair of longitudinally extending gutters, one on each side of the road; providing a first braided pipe, fabricated by weaving together a predetermined number of warps and a lot of woofs made of heat resistant synthetic fibre, along the gutters and the down-stream ends of the top surface of said first layer; providing said gutters with catch basins; communicating said first braided pipe with its associated gutter at locations where its associated gutter is formed with catch basins; and forming a second layer on said first layer. The above method may further comprise disposing a second braided pipe fabricated by weaving together a predetermined number of warps and a lot of woofs made of heat resistant synthetic fiber, said second braided pipe being disposed on said first layer at an angle of substantially 45 degrees with respect to said gutters, said second braided pipe being connected said first braided pipe. In the above methods the first braided pipe may be sheathed with non-woven fabric. The above method may further comprise disposing a second braided pipe fabricated by weaving together a predetermined number of warps and a lot of woofs made of heat resistant synthetic fibre, and disposing said second braided pipe in a slot formed in said first layer at an angle of substantially 45 degrees with respect to said gutters, said second braided pipe being connected to said first braided pipe, said slot in the first layer facing said second layer. According to still another aspect of the present invention, there is provided a drainage system for use with a paved road comprising: a plurality of first braided long pipes which are fabricated by weaving together a predetermined number of warps and a lot of woofs made of heat resistant synthetic fiber and are bent substantially at the center thereof; the first braided long pipes being laid on the base course of a road at predetermined intervals while their bent portions are aligned with the longitudinal center of the road and their ends are disposed at an angle to the longitudinal direction of the road; second braided pipes which are the same as the first braided long pipes and are disposed along gutters on both sides of the road for collecting water; a drainage channel which is formed by connecting the ends of the first braided long pipes with the second braided pipes; and the drainage channel and the base course being surfaced with asphalt mixture. In the drainage system for use with a paved road according to the present invention, a braided pipe is fabricated by weaving together a required number of warps and a lot of woofs using heat resistant synthetic fiber so as to form a drainage channel. The thus fabricated drainage channel is disposed along a gutter on each side of a road and along the downstream-side end of a graded top of the base course of the road. The warps woven into the braided pipe prevent the braided pipe from expanding and shrinking in its longitudinal direction. As a result, the mesh of the braided pipe will not become spread out or reduced, which permits a constant volume of water to be taken at all times. Further, since the braided pipe is flexible, it can follow curves of the road or unevenness and possesses radial pressure resistance. Furthermore, there is no fear of the intrusion of aggregate into the braided pipe, and the rainwater having infiltrated into the surface layer flows in the downstream direction as a result of the gradient of the top surface of the base course. In this way, only the water flows into a drainage guide pipe, thereby preventing the permeation of the rainwater into the base course. Consequently, the rainwater never remains in the pavement, which in turn prevents the fracturing of the pavement. In the drainage system for use with a paved road according to the present invention, a plurality of first braided pipes which are fabricated by weaving together a predetermined number of warps and a lot of woofs of heat resistant synthetic fiber are laid on the base course of the road at predetermined intervals at an angle with respect to the longitudinal direction of the road. These braided pipes on the base course are connected to similar second braided pipes disposed along gutters on both sides of the road, thereby forming a drainage channel. The drainage channel and the first layer are surfaced with asphalt mixture, and consequently the rainwater having penetrated through the road surface flows to catch basins through the first braided pipes on the first layer and the second braided pipes that are disposed along the gutters of the road and are connected to the first braided pipes. In the case of a multi-lane road having a long graded width, the rainwater having permeated through top/second layer of the road surface flows into the braided pipes disposed at an angle with respect to the longitudinal direction of the road when flowing over the graded top of the base course. In this way, it is possible to reliably guide the rainwater flowing over the graded top of the first layer into the braided pipes, i.e., the drainage channel. The downstream-side ends of the first braided pipes on the first layer are connected to the second braided pipes that are disposed along the gutters and are communicated to the catch basins, whereby the rainwater can be effectively drained to the gutters through the catch basins. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a plan view showing a road according to the present invention; Fig. 2 is a cross section of the road taken along line A-A' shown in Fig. 1; Fig. 3 is a perspective view showing the principal elements of a drainage guide pipe; Fig. 4 is a cross-sectional perspective view showing the drainage guide pipe communicated to a drainage gutter; Fig. 5 is a cross-sectional perspective view showing the drainage guide pipe communicated to a catch basin which is connected to an L-shaped gutter; Fig. 6 is a plan view showing a drainage system for use with a paved road according to a second embodiment of the present invention; Fig. 7 is a cross section taken along line A-A' in Fig. 6; Fig. 8 is a cross-sectional perspective view showing a drainage guide pipe communicated to a drainage gutter; Fig. 9 is a cross-sectional perspective view showing a drainage guide pipe communicated to a catch basin which is connected to an L-shaped gutter; Fig. 10 is a plan view showing a drainage system for use with a paved road according to a third embodiment of the present invention; Fig. 11 is a cross section of a paved road with a drainage system according to a fourth embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First embodiment A drainage system for use with a paved road according to a first embodiment of the present invention will now be described with reference to the accompanying drawings. In Figs. 1 and 2, as is conventionally be known, a road 1 is constructed from the base course or base layer 2, and a first layer 3 consisting of coarse asphalt mixtures is laid on top of the base layer 2. The boundary between the base layer 2 and the first layer 3 and the top of the first layer 3 are downwardly graded from the center to both sides of the road 1 in its transverse direction. These graded surfaces are made up of graded portions designated by 4, 4', 5, and 5'. A top or second layer 6 consists of hot asphalt mixtures, and the top surface of the top or second layer 6, i.e., the road surface, is downwardly graded from the center to both ends of the road in its transverse direction in the same manner as the top surface of the first layer 3. In other words, the second layer 6 has graded portions 7 and 7'. In this way, rainwater flows into gutters 8 and 8' provided on both sides of the road 1. As shown in the drawings, catch basins 9 and 9' are disposed in the gutters 8 and 8', as required. A braided pipe 10 formed from heat resistant synthetic fiber is fabricated by weaving together a required number of warps 11, 11 ... (four warps in the present embodiment) and a plenty of woofs 12, 12, 12 .... This synthetic fiber is required to possess heat resistance so that it will be resistant to a pavement temperature of 160 to 180 degrees Centigrade. Polyester, alamide resin, and polyamide are usable as the heat resistant synthetic fiber, and the size of thread should preferably be set to 167-3889 tex (1,500 deniers to 35,000 deniers). Further, the outer diameter of the braided pipe 10 consisting of synthetic fiber has a diameter within the range of 3 to 35 mm. Within this range it can be set to 5 to 25 mm and, preferably, to 10 to 20 mm. Nonwoven fabric 13 is made of the same material as the braided pipe 10, and the surface of the braided pipe 10 is sheathed with this nonwoven fabric 13, thereby forming a drainage guide pipe 14. Since the warps 11 are woven into the braided pipe 10, the braided pipe 10 is prevented from expanding and shrinking in its longitudinal direction, and the meshes of the braided pipe will not become spread out or reduced. Further, the braided pipe 10 is flexible and possesses radial strength. Furthermore, it is possible to design the size of the mesh of the braided pipe at will. The drainage guide pipe 14 is temporarily fixed along the down-stream-side end of the graded top of the first layer 3 and along the gutter 8 longitudinally disposed on the side of the road. A conduit 16 inserted into a bore 15 formed in the side wall of the catch basin 9 facing the first layer 3 is connected to the drainage guide pipe 14. The hot asphalt mixtures are then laid on the drainage guide pipe 14 and the first layer 3, thereby forming the top or second layer 6. The drainage guide pipe 14 is made up of the braided pipes 10 consisting of synthetic fiber, and hence any portion of the drainage guide pipe 14 can permit the flow of water. When being laid along the downstream-side end of the first layer 3 and along the gutter 8, the drainage guide pipe 14 can easily follow curves of the road because the braided pipe 10 forming the drainage guide pipe 14 is flexible. Further, the braided pipe 10 is fabricated by weaving together the warps 11 and the woofs 12, and therefore the warps 11 prevent the braided pipe 10 from expanding and shrinking, thereby facilitating the laying of the braided pipe. In addition, if it becomes necessary to extend a drainage channel consisting of the drainage guide pipe 14, it is possible to extend the drainage channel by only butt-joining a braided pipe 10 to the drainage channel. The drainage guide pipe 14 is laid and temporarily fixed on the first layer 3, and, subsequently, the first layer 3 is surfaced with an asphalt mixture, thereby forming the top second layer 6. As a result, the drainage guide pipe 14 is fixed. The braided pipe 10 forming the drainage guide pipe 14 and the nonwoven fabric 13 covering the surface of the drainage guide pipe 14 are heat resistant and are made of material which can be resistant to a pavement temperature of, for example, 160 to 180 degrees Centigrade. For this reason, the drainage guide pipe 14 will not be damaged as a result of applying the top/second layer 6. Moreover, the braided pipe 10 is cylindrically made of the synthetic fiber which has a required size, and hence it will not be deformed even when it is covered with the top/second layer 6. It is possible to cause the braided pipe 10 to suitably support a required load by changing the diameter of the braided pipe. The drainage channels made up of the drainage guide pipes 14 are disposed along the gutters, and it is very unlikely that a vehicle will run over the drainage channels. In the event that the drainage channels are subject to the load as previously mentioned, it is possible to maintain the drainage function of the drainage channels over a long period of time, because the braided pipe possesses pressure resistance and flexibility. In the drawings, reference numeral 17 designates a cover of the catch basin 9 and 9'. In the present embodiment, the rainwater having infiltrated through the top/second layer 6 flows along the graded portions 5 and 5' of the top/second surface of the first layer 3 into the drainage guide pipes 14 that are disposed along the downstream-side ends of the graded portions of the first layer 3 and along the gutters 8 and 8' and are made by sheathing the surface of the braided pipe 10 with the nonwoven fiber 13. The rainwater then flows into the catch basin 9 via the conduit 16 connected thereto after having flowed through the inside of the drainage guide pipe 14. During the flow of the rainwater into the drainage guide pipe 14, the nonwoven fabric 13 provided over the surface of the drainage guide pipe 14 permits only the rainwater to enter the braided pipe 10. In this way, the rainwater having infiltrated through the top/second surface 6 of the road can be drained to the outside through the drainage guide pipes 14 disposed at the downstreamside ends of the graded top of the first layer 3 along the gutters 8. Therefore, the rainwater neither permeates through nor remains in the first layer 3, thereby preventing the agregate from coming away from the asphalt mixture and preventing, in turn, fracturing of the pavement. In the previously mentioned embodiment, the explanation was given of the drainage guide pipe 14, for draining the rainwater having permeated through the top/second layer 6, which is sheathed with the nonwoven fabric 13 in such a way as to cover the surface of the braided pipe 10. The nonwoven fabric 13 becomes unnecessary depending on the size of the mesh of the braided pipe 10. For example, if the mesh is small, it will be possible to prevent the intrusion of the aggregate, or the like, into the braided pipe 10 without the use of the nonwoven fabric. Figs. 4 and 5 show examples in which the braided pipe 10 is used as a drainage channel 20. Fig. 4 shows an example in which the end of the braided pipe 10 forming the previously mentioned drainage channel 20 is connected to the gutter 8 on one side of the road 1. Fig. 5 is another similar example in which the braided pipe 10 forming the drainage channel 20 is connected to the catch basin 9 that is communicated to an L-shaped ditch 19. The same reference numerals are provided to designate elements corresponding to those of the embodiment shown in Figs. 1 and 2, and these elements are the same in operation as those shown in Figs. 1 and 2. The first layer 3 and the top/second layer 6 are downwardly graded from the center to both ends of the road 1 in its transverse direction in the present embodiment. However, they may be downwardly graded from the both ends to the center separator of the road in its transverse direction. Second embodiment A drainage system for use with a paved road according to a second embodiment of the present invention will now be described with reference to the accompanying drawings. The road of this embodiment is the same in construction as that of the first embodiment. The same reference numerals are provided to designate corresponding elements, and an explanation will be given of solely a difference between the first and second embodiments. In Figs. 6 and 7, the braided pipes 10, 10, 10... formed from synthetic fiber are disposed on the first layer 3 along its longitudional sides at required intervals at an angle with respect to the longitudinal direction of the road 1. The downstream-side ends of the braided pipes 10 are connected to the drainage guide pipes 14 that are disposed on both sides of the road 1 for draining the rainwater to the gutters 8 and 8'. The drainage guide pipe 14 is made up of braided pipes similar to the braided pipes 10. As mentioned above, the drainage guide pipes 14 are temporarily fixed along the downstream-side ends of the graded top surface of the first layer 3 and along the gutters 8 and 8' so as to let the rainwater to flow into the gutters 8 and 8'. The conduit 16 inserted into the bore 15 that is formed in the side wall of the catch basin 9 facing the first layer 3 is connected to the drainage guide pipe 14 made of the braided pipe 10. The downstream-side ends of the braided pipes 10 temporarily fixed on the graded top of the first layer 3 of the road 1 at an angle with respect to the longitudional direction of the road 1 are connected to the drainage guide pipes 14, thereby forming a drainage channel. As previously mentioned, the drainage channel is formed by connecting the drainage guide pipes 14 with the downstream-side ends of the braided pipes 10 temporarily fixed on the graded top of the first layer 3 at an angle with respect to the longitudional direction of the road 1, and, subsequently, the top/second 6 is formed by surfacing the drainage channel and the base course 3 with an asphalt mixture. The drainage channel is fixed as a result of this paving work. The braided pipes 10 forming the drainage channel are made of material that is sufficiently resistant to a pavement temperature of 160 to 180 degrees Centigrade, and therefore the drainage channel will not be damaged as a result of the paving work. Further, since the braided pipes 10 are cylindrically formed from synthetic fiber having a required size, they never deteriorate during the paving work. Furthermore, the braided pipe can deflect by virtue of its mesh, and the end of another braided pipe can be easily inserted into the mesh. In consequence, it is easy to connect another braided pipe to the side of the braided pipe at right angles. In the present embodiment, the rainwater having penetrated through the top/second 6 of the road 1 flows over the graded portions 5 and 5' of the first layer 3 graded toward the gutters on both sides of the road 1. The thus flowing rainwater enters the drainage channel on the first layer 3 which is made up of the braided pipes 10, 10, 10... disposed at an angle with respect to the longitudinal direction of the road 1. The rainwater having flowed into the braided pipes 10, 10, 10... further flows as a result of the gradient of the braided pipes in the downward direction and flows into the drainage guide pipe 14 that is connected to the downstream-side ends of the braided pipes 10 and is made of other braided pipes consisting of the same material as the braided pipe 10. The rainwater then flows into the catch basin 9 via the conduit 16 connected to the catch basin 9 after having flowed through the inside of the drainage guide pipe 14. As previously mentioned, it is possible for the rainwater having penetrated through the top/second layer 6 of the road 1 to flow into the braided pipes 10, 10, 10... disposed on the top surface of the first layer 3 at an angle to the longitudinal direction of the road 1. For this reason, even if the width over which the rainwater flows is increased as in a multi-lane road, the rainwater is guided to the braided pipes and easily flows through the pipes. The rainwater can be drained to the outside via the drainage guide pipe 14 that is provided at the downstream-side ends of the first layer 3 and is disposed along the gutters 8 and 8'. In consequence, the rainwater neither permeates through nor remains in the first layer 3, thereby preventing the aggregate from coming away from the asphalt mixture and preventing, in turn, fracturing of the pavement. The surface of the braided pipe 10 may be sheathed with the nonwoven fabric 13, as required. As a result, it becomes possible to introduce only the rainwater into the braided pipe 10. Figs. 8 and 9 show examples wherein the drainage channel 20 is formed from the drainage guide pipe 14 comprising braided pipes disposed along the gutter 8 and from the plurality of braided pipes 10 which are disposed on the first layer 3 at an angle with respect to the longitudinal direction of the road and are connected to the drainage guide pipe 14. Fig. 8 shows an example in which the end of the drainage guide pipe 14 is connected to the gutter 8 on one side of the road 1. Fig. 9 is another similar example in which the drainage guide pipe 14 is connected to the catch basin 9 that is communicated to the L-shaped ditch 19. The same reference numerals are provided to designate elements corresponding to those of the second embodiment shown in Figs. 6 and 7, and these elements are the same in operation as those of the second embodiment. In the second embodiment, the explanation was given of the first layer 3 and the top layer 6 are downwardly graded from the center to both ends of the road 1 in its transverse direction. However, they may be downwardly graded from both ends to the center separator of the road 1 in its transverse direction. Third embodiment Fig. 10 shows a drainage system for use with a paved road according to a third embodiment of the present invention. The braided long pipe 10 is bent substantially at its center 31, and it is disposed on the first layer 3 of the road 1 while its bent portion is aligned with the longitudinal center of the road 1. Legs 10a and 10b of the braided long pipe 10 are temporarily fixed on the portions of the top surface of the first layer 3 that are graded toward the gutters 8 and 8' while being arranged at predetermined intervals at an angle with respect to the longitudinal direction of the road 1. The downstream-side ends of the legs 10a and 10b are connected to the drainage guide pipes 14 and 14 disposed along the gutters 8 and 8'. The braided pipes 10 and the drainage guide pipes 14 connected thereto are surfaced with asphalt mixture. The same reference numerals are provided to designate elements corresponding to the elements of the first embodiment shown in Figs. 1 and 2, and these elements are the same in operation as those of the second embodiment. Fourth embodiment Fig. 11 shows a drainage system for use with a paved road according to a fourth embodiment of the present invention. In the present embodiment, the road is grooved, for example, at an angle with respect to its longitudinal direction, so that slots 22 are formed. The braided pipes 10 consisting of the synthetic fiber are fitted into these slots 22. The second and third embodiments are applied to the braided pipes 10 fitted into the slots 22, thereby forming the drainage system for use with the paved road. The slots 22 are not only formed by grooving but by any other alternative means. The braided pipes 10 of the present embodiment are disposed on the first layer 3 at an angle in relation to the longitudinal direction of the road. Although the angle is not limited to a specific angle, they should preferably be disposed at an angle of substantially 45 degrees with respect to the longitudinal direction of the road. The interval between the braided pipes 10 is not limited to a specific value. However, the interval should preferable be determined in such a way that an imaginary line crossing the longitudinal center line of the road at right angles at the bent portion of one braided pipe 10 intersects both downstream-side ends of the adjacent braided pipe. As previously mentioned, the drainage channel is made up of the braided pipe that consists of synthetic fiber, and hence any part of the drainage channel permits the flow of water. If the drainage channel is extended or is connected to another drainage channel at right angles, the drainage channel can be extended or divided by only butt-joining the braided pipe in another drainage channel or sticking the end of the braided pipe into the mesh of another drainage channel, thereby providing a degree of freedom of design for a drainage channel. In the drainage system for use with a paved road according to the present invention, a plurality of first braided pipes which are fabricated by weaving a plenty of heat resistant synthetic fiber are laid on the first layer of the road at predetermined intervals at an angle with respect to the longitudinal direction of the road. The gutter-side ends of the braided pipes are connected to a similar second braided pipe, that is, a drainage guide pipe which is disposed along a gutter on each side of the road and is connected to the catch basins, thereby forming a drainage channel. The asphalt mixture is laid on the top surfaces of the drainage channel and the first layer. As a result, the rainwater having penetrated through the road surface and flowed along the graded top surface of the first layer flows into the braided pipe disposed on the first layer at an angle to the longitudinal direction of the road from the side of the braided pipe. The rainwater is then collected to the drainage guide pipe that is connected to the gutter-side ends of the braided pipes, and the thus collected rainwater is drained to the gutter via the drainage guide pipe. In this way, the rainwater is prevented from permeating through or remaining in the first layer, which in turn prevents the aggregate from coming away from the asphalt mixture. Particularly in the present invention, a plurality of braided pipes are disposed on the first layer course at an angle with respect to the longitudinal direction of the road so as to take the rainwater flowing over the top surface of the first layer With this construction, the rainwater linearly flowing over the graded top surface of the first layer in the downstream direction meets and flows into the side of the braided pipe through its meshes. For this reason, even if the width over which the rainwater flows is increased as in the multi-lane road, the rainwater is guided along the inside of the braided pipe, and it can be efficiently drained. If the braided pipes are fixedly fitted into a plurality of slots grooved in the first layer of the road at predetermined intervals at an angle with respect to the longitudinal direction of the road, the braided pipes fixedly remain in their positions while being paved. Further, it becomes possible to ensure the inflow of the rainwater into the braided pipes. The asphalt pavement is cut and removed from the waterproof layer for maintenance or repair of the road after the lapse of a predetermined period of time, and the waterproof layer is paved again. The drainage channel that is made up of the braided pipes consisting of heat resistant synthetic fiber can be removed without putting a strain on or providing damage to a cutting machine when they are cut. Even if the removed asphalt pavement is fed into a crusher for recycling purposes, no problems will arise. Further, it is easy to separate only the drainage channel from the water proof layer. The volume of wastes resulting from separation and discarding of the removed asphalt mixture becomes small, which results in superior workability.

Claims: A drainage system for use with a paved road comprising: a base layer; a first layer laid on said base layer; a second layer laid on said first layer; a pair of gutters longitudinally provided one on each side of said road; a first braided pipe fabricated by weaving together a predetermined number of warps and a lot of woofs made of heat resistant synthetic fiber, said braided pipe being disposed along the gutter and the downstream-side end of the top surface of said first layer; the first braided pipe being communicated to the gutter at locations where the gutter is formed with catch basins. A drainage system for use with a paved road as claimed in Claim 1, wherein said first braided pipe is sheathed with non-woven fabric. A drainage system for use with a paved road as claimed in Claim 1, further comprising: a second braided pipe fabricated by weaving together a predetermined number of warps and a lot of woofs made of heat resistant synthetic fiber, said second braided pipe being disposed on said first layer at an angle of substantially 45 degrees with respect to said gutters, said second braided pipe being connected to said first braided pipe. A drainage system for use with a paved road as claimed in Claim 3, wherein said second braided pipe is fitted into a slot formed in said second layer. A drainage system for use with a paved road as claimed in any of claims 1 and 3, wherein said braided pipe has a diameter within 3 to 35 mm. A drainage system for use with a paved road as claimed in any of claims 1 and 3, wherein said heat resistant synthetic fiber is selected from the group consisting of Polyester, alamide resin and polyamide with a size with thread being set to 167 to 3889 tex (1500 to 35,000 deniers). A method for producing a drainage system for use with a paved road comprising the steps of: forming a base layer; forming a first layer on said base layer; providing a pair of longitudinally extending gutters, one on each side of the road; providing a first braided pipe, fabricated by weaving together a predetermined number of warps and a lot of woofs made of heat resistant synthetic fibre, along the gutters and the down-stream ends of the top surface of said first layer; providing said gutters with catch basins; communicating said first braided pipe with its associated gutter at locations where its associated gutter is formed with catch basins; and forming a second layer on said first layer. A method for producing a drainage system for use with a paved road as claimed in Claim 7, further comprising: disposing a second braided pipe fabricated by weaving together a predetermined number of warps and a lot of woofs made of heat resistant synthetic fiber, said second braided pipe being disposed on said first layer at an angle of substantially 45 degrees with respect to said gutters, said second braided pipe being connected said first braided pipe. A method for producing a drainage system for use with a paved road as claimed in Claim 8, wherein said first braided pipe is sheathed with non-woven fabric. A drainage system for use with a paved road as claimed in Claim 3, wherein said second braided pipe is fitted into a slot formed in said first layer, said slot in the first layer facing said second layer. A method for producing a drainage system for use with a paved road as claimed in Claim 7, and further comprising: disposing a second braided pipe fabricated by weaving together a predetermined number of warps and a lot of woofs made of heat resistant synthetic fibre, and disposing said second braided pipe in a slot formed in said first layer at an angle of substantially 45 degrees with respect to said gutters, said second braided pipe being connected to said first braided pipe, said slot in the first layer facing said second layer. A drainage system for use with a paved road as claimed in Claim 3 wherein said second braided pipe is bent substantially at the center thereof, the bent portion being aligned with the longitudinal center of the road, said second braided pipe having one of the ends connected to a said first braided pipe on one side of the road; and having the other of its ends connected to a said first braided pipe on the other side of the road.

Inventors: SAKUMA YOSHIMITSU, SASAKI YOSHIOMI, SATO ISAO, SAKUMA, YOSHIMITSU, SASAKI, YOSHIOMI, SATO, ISAO, Sakuma, Yoshimitsu, c/o Shoseki Kakoh K.K., Sasaki, Yoshiomi, c/o Maeda Kosen Co., Ltd., Sato, Isao, c/o Shoseki Kakoh K.K.
Applicants: SHOWA SHELL SEKIYU, SHOWA SHELL SEKIYU KABUSHIKI KAISHA
Application year: 1995
Main classification: E01C1
IPC codes: E01D19, E01C11