Abstract:
A reinforcing geotextile mat and an embankment method using the same. The mat comprises support means for supporting backfilled soil at one end or both ends of the mat. The support means comprises a horizontal support section for supporting the backfilled soil in a vertical direction; a vertical support section for supporting the backfilled soil in a horizontal direction; and an inclined support section defined with openings through which the backfilling soil passes and inclinedly embedded in the backfilled soil. The method comprises the steps of positioning a reinforcing geotextile mat on the ground or hardened embankment soil; inserting external support members in horizontal, vertical and inclined receiving portions of the mat; and backfilling horizontal, vertical and inclined support sections of the mat with soil, and then placing and hardening embankment soil on the mat. These steps are implemented one or more times.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates, in general, to a reinforcing geotextile mat and an embankment method using the same, and more particularly, to a reinforcing geotextile mat which is manufactured by assembling support members in a geotextile mat to serve as a retaining wall and an embankment method which uses the reinforcing geotextile mat to reduce the construction cost and shorten the construction period.  
         [0003]     2. Description of the Prior Art  
         [0004]     Due to environmental or economic issues, it is frequently required to form a steeply inclined natural or artificial slope. In such a situation, in order to secure structural and dynamic stability of the slope, multiple layers of geotextile are used while constructing the slope.  
         [0005]     In addition to the case of forming a steeply inclined slope, geotextile is used in the case of restoring a broken slope with the aim of reinforcing the ground.  
         [0006]     In addition, geotextile is used to reinforce areas upstream and downstream from a dam and increase the height of the dam, construct a temporary flood control structure, reinforce an abutment of a bridge and decrease the span of the bridge, construct a temporary bypass road, and construct a levee using water-containing fine particles.  
         [0007]     An example of a conventional construction method using the geotextile is disclosed in Korean Patent No. 10-419883 entitled “Slope plantation earth reinforcement method”, which will be described with reference to  FIGS. 8   a  through  8   i.    
         [0008]     The conventional slope plantation earth reinforcement method is implemented as described below.  
         [0009]     As shown in  FIG. 8A , after the in-situ ground is hardened, a plurality of steel bars  10  are laid out on the in-situ ground.  
         [0010]     Next, as shown in  FIG. 8B , support tubes  36  of a form board  30  are inserted around ends of the steel bars  10  to fix the form board  30  at a predetermined position.  
         [0011]     Then, as shown in  FIG. 8C , a vegetation mat  40  and a lapping textile  42  are installed on the in-situ ground and the form board  30 , and then a first embankment layer  52  having a predetermined height is formed and hardened on the in-situ ground.  
         [0012]     Thereafter, as shown in  FIG. 8D , a step-shaped embankment wall  54  is formed on the first embankment layer  52 .  
         [0013]     Successively, as shown in  FIG. 8E , the first embankment layer  52  and the embankment wall  54  are lapped using a lapping textile  42 .  
         [0014]     Next, as shown in  FIG. 8F , a second embankment layer  56  is formed on the first embankment layer  52  to have the same height as a support section  32 .  
         [0015]     Then, as shown in  FIG. 8G , by moving the form board  30  forward by a predetermined distance and fixing the form board  30  to steel bars  10 ,  
         [0016]     Then, as shown in  FIG. 8H , a predetermined space  57  is defined in front of the embankment layers  52  and  56 , and a vegetation soil layer  58  is formed in the space  57 .  
         [0017]     Finally, as shown in  FIG. 8I , the upper part of the vegetation soil layer  58  is covered by a vegetation mat  40 , and ends of the vegetation mat  40  are appropriately fixed.  
         [0018]     However, the conventional earth reinforcement method has a drawback in that, since the form board must be repeatedly installed and uninstalled in order to form the embankment layers, the construction cost increases and the construction period is lengthened.  
         [0019]     Further, because an embankment layer may only be formed after a previous embankment layer is completely hardened, the construction period is further lengthened.  
         [0020]     Meanwhile, U.S. Pat. No. 5,161,917 discloses a method of and an element for the production of structures for containing areas of ground. In this publication, an element for use in producing stabilized soil structures comprises a sheet of double-twisted galvanized and plastic-coated metal mesh which has on one end a box portion made from panel of the sheet panels and folded up from the end of the sheet and an additional transverse panel fixed to the sheet. In use, a plurality of elements are superposed with the box portions providing the anterior wall of the structure and the remainder of each sheet extending back into the structure to stabilize the structure. Each element is filled and covered with fill material before a succeeding element is positioned on it. The fold lines of panels are defined by strips introduced into the mesh of sheet during manufacture.  
         [0021]     This conventional technique suffers from defects in that, since the box portions must be folded and installed in situ, workability is degraded, and since specific holding means is not provided, it is difficult to handle the element.  
         [0022]     Also, U.S. Pat. No. 6,357,970 discloses an improved method and apparatus for constructing a soil reinforced earthen retaining wall. In this publication, successive soil reinforcing mats embedded within an earthen formation have bent-up face elements which are slidably engaged to enable the earthen formation to settle without bulging the face elements. Backing mats are disposed behind the face elements for movement relative thereto in generally vertical planes. The backing mats serve to support the successive soil reinforcing mats and permit the mats to more toward one another to accommodate settling of the formation without bulging of the face elements.  
         [0023]     However, this technique still encounters the same problems as described above in connection with the conventional arts.  
       SUMMARY OF THE INVENTION  
       [0024]     Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a reinforcing geotextile mat which has support members capable of supporting an embankment layer.  
         [0025]     Another object of the present invention is to provide an embankment method which uses a reinforcing geotextile mat to reduce a construction cost and shorten a construction period.  
         [0026]     In order to achieve the first object, according to one aspect of the present invention, there is provided a reinforcing geotextile mat comprising support means arranged at both ends of the reinforcing geotextile mat, to support a predetermined amount of embankment soil, with a portion of each support means embedded in backfilled soil.  
         [0027]     According to another aspect of the present invention, there is provided a reinforcing geotextile mat comprising support means arranged at one end of the reinforcing geotextile mat, to support a predetermined amount of embankment soil, with a portion of the support means embedded in backfilled soil; and an accommodating section arranged at the other end of the reinforcing geotextile mat, to accommodate an element to be fixedly held, with the entire accommodating section embedded in the embankment soil.  
         [0028]     According to another aspect of the present invention, the support means comprises a horizontal support section for supporting the backfilled soil in a vertical direction; a vertical support section for supporting the backfilled soil in a horizontal direction; and an inclined support section defined with openings through which the backfilling soil passes and inclinedly embedded in the backfilled soil.  
         [0029]     According to another aspect of the present invention, when assuming that lengths of the horizontal support section, the vertical support section and the inclined support section are respectively L H1 , L V1  and L C1 , L H1 =3.5˜4.5*L V1  and L C1 =3.9˜5.0*L V1 .  
         [0030]     According to another aspect of the present invention, the horizontal support section, the vertical support section and the inclined support section have a horizontal receiving portion, a vertical receiving portion and an inclined receiving portion, respectively, into which external support members for increasing supporting force are inserted.  
         [0031]     According to another aspect of the present invention, when assuming that lengths of the horizontal receiving portion, the vertical receiving portion and the inclined receiving portion are respectively L H2 , L V2  and L C2 , L H2 =0.6˜1.0*L V2  and L C2 =0.2˜0.5*L V2 .  
         [0032]     In order to achieve the second object, according to another aspect of the present invention, there is provided an embankment method using a reinforcing geotextile mat, comprising (a) step for positioning the reinforcing geotextile mat on the ground or hardened embankment soil in a deployed state; (b) step for inserting external support members in a horizontal receiving portion, a vertical receiving portion and an inclined receiving portion of the reinforcing geotextile mat; and (c) step for backfilling a horizontal support section, a vertical support section and an inclined support section of the reinforcing geotextile mat with soil, and then placing and hardening embankment soil on the reinforcing geotextile mat so that the embankment soil has a predetermined height, wherein steps (a), (b) and (c) are implemented one or more times.  
         [0033]     According to still another aspect of the present invention, step (b) comprises the step of inserting the external support members through the receiving portions of a plurality of reinforcing geotextile mats to laterally couple the plurality of reinforcing geotextile mats to one another.  
         [0034]     According to yet still another aspect of the present invention, step (c) comprises the step of installing a drainpipe defined with a plurality of through-holes, adjacent to the support sections of the reinforcing geotextile mat. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0035]     The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description when taken in conjunction with the accompanying drawings, in which:  
         [0036]      FIG. 1  is a schematic perspective view illustrating a reinforcing geotextile mat in accordance with a first preferred embodiment of the present invention;  
         [0037]      FIGS. 2A through 2C  are schematic views illustrating a procedure for manufacturing the reinforcing geotextile mat shown in  FIG. 1 ;  
         [0038]      FIG. 3  is a schematic perspective view illustrating a reinforcing geotextile mat in accordance with a second preferred embodiment of the present invention;  
         [0039]      FIGS. 4A through 4C  are schematic views illustrating a procedure for manufacturing the reinforcing geotextile mat shown in  FIG. 3 ;  
         [0040]      FIGS. 5A through 5E  are schematic views illustrating an embankment method in accordance with a third preferred embodiment of the present invention, which uses the reinforcing geotextile mat shown in  FIG. 1 ;  
         [0041]      FIGS. 6A through 6E  are schematic views illustrating an embankment method in accordance with a fourth preferred embodiment of the present invention, which uses the reinforcing geotextile mat shown in  FIG. 3 ;  
         [0042]      FIG. 7  is a schematic view illustrating a state in which a plurality of reinforcing geotextile mats shown in  FIGS. 1 and 3  are coupled to one another; and  
         [0043]      FIGS. 8A through 8I  are schematic views illustrating a conventional earth reinforcement method. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0044]     Reference will now be made in greater detail to preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings and the description to refer to the same or like parts.  
         [0045]     First, reinforcing geotextile mats in accordance with preferred embodiments of the present invention will be described with reference to  FIGS. 1 through 4 C.  
       First Embodiment  
       [0046]     A reinforcing geotextile mat in accordance with a first preferred embodiment of the present invention will be described with reference to  FIGS. 1 through 2 C.  
         [0047]     As shown in  FIG. 1 , a reinforced geotextile mat  100  has at both ends thereof support means each of which serves as a retaining wall for supporting embankment soil.  
         [0048]     The support means is composed of an inclined support section  110 , a vertical support section  120  and a horizontal support section  130 .  
         [0049]     The inclined support section  110  is a section to be embedded and fixedly maintained in the embankment soil. The inclined support section  110  is formed with a first opening  101 , a second opening  102  and a third opening  103 .  
         [0050]     While, in this embodiment of the present invention, the openings  101 ,  102  and  103  are defined to have a rectangular shape, the shape and number of the openings are not specifically limited so long as backfilling soil can easily pass through the openings.  
         [0051]     The inclined support section  110  has a first stitched portion  111 , a second stitched portion  112  and a third stitched portion  113  which are formed by turning over or superposing and stitching one or more cut portions of the reinforcing geotextile mat  100 .  
         [0052]     In this way, by turning over or superposing one or more cut portions at one side or both sides of each of the openings  101 ,  102  and  103  and then forming the stitched portions  111 ,  112  and  113 , the tensile strength of the inclined support section  110  is increased.  
         [0053]     The vertical support section  120  is a section to support backfilled soil in a horizontal direction, and has a first superposed portion  121  which is partially connected to the inclined support section  110 .  
         [0054]     A vertical receiving portion  132  into which a first external support member (not shown) is inserted is formed between the vertical support section  120  and the first superposed portion  121 , and an inclined receiving portion  131  into which the first external support member (not shown) is inserted is formed between the inclined support section  110  and the first superposed portion  121 .  
         [0055]     While, in this embodiment, the inclined receiving portion  131  and the vertical receiving portion  132  are formed to communicate with each other, it is to be readily understood that they may be formed to be partitioned from each other.  
         [0056]     The horizontal support section  130  is a section to support the backfilled soil in a vertical direction, and is connected at one end thereof to the vertical support section  120  and at the other end thereof to a base  150  of the reinforcing geotextile mat  100 .  
         [0057]     The horizontal support section  130  has a second superposed portion  122 .  
         [0058]     A horizontal receiving portion  133  into which a second external support member (not shown) is inserted is formed between the horizontal support section  130  and the second superposed portion  122 .  
         [0059]     When assuming that lengths of the inclined support section  110 , the vertical support section  120  and the horizontal support section  130  are respectively L H1 , L V1  and L C1 , lengths of the inclined receiving portion  131 , the vertical receiving portion  132  and the horizontal receiving portion  133  are respectively L H2 , L V2  and L C2 , and L V1 ≅L V2 =L, it is preferred from structural and dynamic points of view that the lengths satisfy the following equations 1. 
 
 L   C1 =3.9˜5.0 *L  
 
 L   H1 =3.5˜4.5 *L  
 
 L   C2 =0.2˜0.5 *L  
 
 L   H2 =0.6˜1.0 *L   [Equations 1]
 
         [0060]     The above-described reinforcing geotextile mat  100  is manufactured as shown in  FIGS. 2A through 2C .  
         [0061]     First, as shown in  FIG. 2A , on each end of the reinforcing geotextile mat  100 , the first opening  101 , the second opening  102  and the third opening  103  are defined by cutting portions of the reinforcing geotextile mat  100  to have a predetermined interval and a predetermined length.  
         [0062]     Next, as shown in  FIG. 2B , in order to form the openings  101 ,  102  and  103 , one or more cut portions are turned over or superposed and then stitched to the reinforcing geotextile mat  100  to form the first stitched portion  111 , the second stitched portion  112  and the third stitched portion  113 .  
         [0063]     Further, a piece of preselected material, preferably, a piece of geotextile, is superposed on the reinforcing geotextile mat  100  adjacent to the openings  101 ,  102  and  103  and then stitched to the reinforcing geotextile mat  100  to form the first superposed portion  121 , the second superposed portion  122 , a fourth stitched portion  114 , a fifth stitched portion  115  and a sixth stitched portion  116 .  
         [0064]     At this time, it is preferred that the length of the first superposed portion  121  be set to be slightly greater than the sum of the lengths of the inclined receiving portion  131  and the vertical receiving portion  132 , and the length of the second superposed portion  122  be set to be slightly greater than the length of the horizontal receiving portion  133 .  
         [0065]     Finally, as shown in  FIG. 2C , a portion of the reinforcing geotextile mat  100 , which is to be formed as the inclined support section  110  having the openings  101 ,  102  and  103 , is folded in the direction indicated by the arrow, and the distal end of the folded portion is stitched to the reinforcing geotextile mat  100  to form a seventh stitched portion  117 .  
       Second Embodiment  
       [0066]     A reinforcing geotextile mat in accordance with a second preferred embodiment of the present invention will be described with reference to  FIGS. 3 through 4 C.  
         [0067]     As shown in  FIG. 3 , a reinforcing geotextile mat  200  has support means which is arranged at one end of the reinforcing geotextile mat  200  and serves as a retaining wall for supporting embankment soil, and an accommodating section  260  which is arranged at the other end of the reinforcing geotextile mat  200  and is embedded in the embankment soil to accommodate an element to be fixed and thereby fixedly hold the reinforcing geotextile mat  200  with respect to the embankment soil.  
         [0068]     Since the support means is constructed in the same manner as in the first embodiment, detailed description thereof will be omitted herein.  
         [0069]     The accommodating section  260  is defined by forming an eighth stitched portion  118  through folding the other end of the reinforcing geotextile mat  200  and stitching the folded end to the reinforcing geotextile mat  200 .  
         [0070]     While it is preferred that the accommodating section  260  be embedded in the embankment soil in a state in which a drainpipe  290  having a predetermined length is accommodated in the accommodating section  260 , the accommodating section  260  can be embedded in the embankment soil without using the drainpipe  290 .  
         [0071]     The drainpipe  290  not only serves to fixedly hold the reinforcing geotextile mat  200  in the embankment soil, but also is formed with a plurality of through-holes  291  to drain water contained in the embankment soil to the outside.  
         [0072]     The above-described reinforcing geotextile mat  200  is manufactured as shown in  FIGS. 4A through 4C .  
         [0073]     First, as shown in  FIG. 4A , on one end of the reinforcing geotextile mat  200 , a first opening  201 , a second opening  202  and a third opening  203  are defined by cutting portions of the reinforcing geotextile mat  200  to have a predetermined interval and a predetermined length, and from the other end of the reinforcing geotextile mat  200 , a folding portion  200   a  having a predetermined length is established.  
         [0074]     Next, as shown in  FIG. 4B , in order to form the openings  201 ,  202  and  203 , one or more cut portions are turned over or superposed and then stitched to the reinforcing geotextile mat  200  to form a first stitched portion  211 , a second stitched portion  212  and a third stitched portion  213 .  
         [0075]     Further, a piece of preselected material, preferably, a piece of geotextile, is superposed on the reinforcing geotextile mat  200  adjacent to the openings  201 ,  202  and  203  and then stitched to the reinforcing geotextile mat  200  to form a first superposed portion  221 , a second superposed portion  222 , a fourth stitched portion  214 , a fifth stitched portion  215  and a sixth stitched portion  216 . And, the folding portion  200   a  is folded and stitched to the reinforcing geotextile mat  200  to form an eighth stitched portion  218 .  
         [0076]     At this time, it is preferred that the length of the first superposed portion  221  be set to be slightly greater than the sum of the lengths of an inclined receiving portion  231  and a vertical receiving portion  232 , and the length of the second superposed portion  222  be set to be slightly greater than the length of a horizontal receiving portion  233 .  
         [0077]     Finally, as shown in  FIG. 4C , a portion of the reinforcing geotextile mat  200 , which is to be formed as an inclined support section  210  having the openings  201 ,  202  and  203 , is folded in the direction indicated by the arrow, and the distal end of the folded portion is stitched to the reinforcing geotextile mat  200  to form a seventh stitched portion  217 .  
         [0078]     Next, embankment methods in accordance with preferred embodiments of the present invention will be described with reference to  FIGS. 5A through 6E .  
       Third Embodiment  
       [0079]     An embankment method in accordance with a third preferred embodiment of the present invention which uses the reinforcing geotextile mat shown in  FIG. 1  will be described with reference to  FIGS. 5A through 5E .  
         [0080]     First, as shown in  FIG. 5A , the reinforcing geotextile mat  100  is positioned on the ground in a deployed state.  
         [0081]     Next, as shown in  FIG. 5B , by inserting the first external support member  141  into the inclined receiving portion  131  and the vertical receiving portion  132  and inserting the second external support member  142  into the horizontal receiving portion  133 , the retaining wall for supporting the backfilled soil is formed. At this time, the embankment soil  10  is placed on the reinforcing geotextile mat  100 . In the case that a drainage system is required, depending upon the circumstances at an embankment installation spot, a drainpipe  143  may be installed at a predetermined location.  
         [0082]     Then, as shown in  FIG. 5C , after implementing backfilling work by evenly distributing the embankment soil  10 , the embankment soil  10  is hardened to have a predetermined height.  
         [0083]     Thereupon, as shown in  FIG. 5D , after a new reinforcing geotextile mat  100  is deployed on the embankment soil hardened in this way, the above-described procedure is repeated. In this regard, it is preferred that the size of the new mat installed on the hardened embankment soil be less than that of the previously installed mat.  
         [0084]     Finally, as shown in  FIG. 5E , green soil  20  is provided to each stepped portion which is formed between two layers of embankment soil.  
       Fourth Embodiment  
       [0085]     An embankment method in accordance with a fourth preferred embodiment of the present invention which uses the reinforcing geotextile mat shown in  FIG. 3  will be described with reference to  FIGS. 6A through 6E .  
         [0086]     First, as shown in  FIG. 6A , the reinforcing geotextile mat  200  is positioned in a deployed state on the ground being adjacent to a slope  30 .  
         [0087]     Next, as shown in  FIG. 6B , by inserting a first external support member  241  into the inclined receiving portion  231  and the vertical receiving portion  232  and inserting a second external support member  242  into the horizontal receiving portion  233 , the retaining wall for supporting the backfilled soil is formed. At this time, the embankment soil  10  is placed on the reinforcing geotextile mat  200 . In the case that a drainage system is required, depending upon the circumstances at an embankment installation spot, a drainpipe  243  may be installed at a predetermined location.  
         [0088]     Then, as shown in  FIG. 6C , after implementing backfilling work by evenly distributing the embankment soil  10 , the embankment soil  10  is hardened to have a predetermined height.  
         [0089]     Thereupon, as shown in  FIG. 6D , after a new reinforcing geotextile mat  200  is deployed on the embankment soil hardened in this way, the above-described procedure is repeated. In this regard, it is preferred that the size of the new mat installed on the hardened embankment soil be less than that of the previously installed mat.  
         [0090]     Finally, as shown in  FIG. 6E , green soil  40  is provided to each stepped portion formed between two layers of embankment soil.  
         [0091]     A plurality of the reinforcing geotextile mats  100  and  200  according to the above-described embodiments can be used in a state in which they are coupled to each other as shown in  FIG. 7 .  
         [0092]     As shown in the drawing, by placing the reinforcing geotextile mats  100  and  200  parallel to each other and inserting the first external support members  141  and  241  and the second external support members  142  and  242  through the inclined receiving portions  131  and  231 , the vertical receiving portions  132  and  232  and the horizontal receiving portions  133  and  233  of the respective reinforcing geotextile mats  100  and  200 , the plurality of mats  100  and  200  are coupled with one another.  
         [0093]     At this time, it is to be noted that the first external support members  141  and  241  may be used in a bent state or may comprise two separate members.  
         [0094]     As apparent from the above description, the reinforcing geotextile mat according to the present invention provides advantages in that, since the reinforcing geotextile mat itself has support members capable of supporting backfilled soil, auxiliary support structures such as a retaining wall and so forth are not needed when implementing the embankment.  
         [0095]     Also, due to the fact that an inclined support section of the reinforcing geotextile mat is defined with a plurality of openings, it is possible to backfill soil through the openings.  
         [0096]     Further, because the reinforcing geotextile mat has a plurality of superposed portions and stitched portions, the reinforcing geotextile mat has increased tensile strength.  
         [0097]     Moreover, due to the fact that the reinforcing geotextile mat can be manufactured in large quantities for various sizes in a factory and then can be used through simple assembly work at embankment implementation spots, a construction cost can be significantly reduced.  
         [0098]     Furthermore, as a plurality of reinforcing geotextile mats can be used in a state in which they are connected to one another, the reinforcing geotextile mat can be freely used irrespective of the scale of an embankment implementation spot.  
         [0099]     In addition, the embankment method according to the present invention which uses the above-described reinforcing geotextile mat provides advantages in that, since it is possible to stack another reinforcing geotextile mat on an embankment layer in a state in which backfilled soil of the embankment layer has not completely hardened, a construction period can be remarkably shortened.  
         [0100]     Although preferred embodiments of the present invention have been described for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.