Abstract:
A fastening system is invented for fasten the soil nails (which are used in cut areas) and the reinforced retaining structures (which are used in fill areas). The system is to connect the two and form an integrated body to prevent sliding plane passing through the interface of the two. The fastening system includes coupling elements, struts, flanges, steel pipes, cables, annular sleeve and clamps.

Description:
FIELD OF THE INVENTION 
     The present invention relates to fastening structure for coupling soil nails and reinforced soil retaining wall. 
     BACKGROUND OF THE INVENTION 
     In recent years, reinforced soil retaining walls have been extensively used to replace conventional concrete wall for fill work. For cutting areas, soil nailings are developed to reinforce the existing ground for preventing landslides. However, there is a need to combine soil nailing and reinforced soil structure if both cut and fill conditions are encountered at the same time. 
     SUMMARY OF THE INVENTION 
     The primary object of the invention is to fulfill aforesaid needs. The invention provides a fastening structure to couple soil nailing and reinforced soil retaining wall for forming an integrated structure. 
     Another object of the invention is to utilize resistant force of the reinforced retaining wall to increase the stability of the soil nailing on the excavation site and offers a construction method safer than conventional soil nailing construction technique. 
     Yet another object of the invention is to fasten the soil nailing and the reinforced soil retaining wall to become an integrated body to prevent sliding plane from passing through the interface of the two. 
     In order to achieve the foregoing objects, the retaining structure of the invention includes soil nailings, a fastening structure and a reinforced retaining wall. The soil nailings are installed and buried into the earth through the wall of the work site, and then the fastening structure is assembled to the soil nailing. Finally, the reinforced retaining wall is fastened to the fastening structure to complete the construction of the invention. 
     The construction thus combines and integrates the soil nailing and reinforced soil walls to increase the stability of the whole system. After a number of soil nailings have been installed into the slope wall, zinc coated and spot soldered wire meshes are laid with non-woven fabrics and water permeable gravel materials on sloped wall over the soil nailings, then fasten the reinforced retaining wall to the soil nailings. 
     The following is a detailed description of the invention with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic view of excavating a construction site on a slope land. 
     FIG. 2 is a schematic view of first soil nailing installation. 
     FIG. 3 is a schematic view of the completed set of soil nailings. 
     FIG. 4 is a schematic view of zinc coated and spot soldered wire meshes, non-woven fabrics and water permeable gravel materials laid on the excavated area. 
     FIG. 5A is a schematic view of fastening the reinforced retaining wall to soil nailing. 
     FIG. 5B is an enlarged view of FIG.  5 A. 
     FIG. 6 is a schematic view of the fastening structure of the invention, coupling with a soil nailing. 
     FIG. 7 is an enlarged view of FIG. 5B, for a single reinforced layer. 
     FIG. 8 is a schematic view of the invention with the reinforced materials (geogrid or grill meshes) fastened to soil nailing. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIGS. 1,  2  and  3  for an embodiment of the invention, prior to the construction and installation of the invention, setup a work site  1  by excavating a slope land. After the work site  1  is ready, install soil nailing  2  into the earth through the wall of the work site  1 . After complete installation of the soil nailing  2 , lay a zinc-coated and spot-soldered wire meshes  3 , non-woven fabrics  4  and water permeable gravel materials  5  on the slope wall over the soil nailing (as shown in FIG. 4) to ensure safety and convenience of the work in the later phases. Then the work for fastening the soil nailing  2  and reinforced retaining wall  6  (as shown in FIG. 5A) may be started. 
     Referring to FIGS. 5B and 6, to fasten the soil nailing  2  and reinforced retaining wall  6 , each soil nailing  2  is engaged with a fastening means  7 . The fastening means  7  includes a coupling element  71  and a strut  72  made of solid or hollow steel pipes. The coupling element  71  has an annular sleeve  712  to hold the strut  72  and a flange  711  engaging with the soil nailing  2  through a fasten element  21  made of a screw nut. A series of soil nailing  2  may be linked and fastened by a series of struts  72  (as shown in FIG.  8 ). 
     Referring to FIGS. 7 and 8, after the fastening means  7  is assembled on the soil nailing  2 , install the reinforced retaining wall  6  on the fastening means  7 . 
     The reinforced retaining wall  6  includes a reinforced grill mesh or geogrid  61 , a support beam  62 , a rope  63  and a clamp means  64 . The reinforced grill mesh or geogrid  61  is to reinforce retaining earth (not shown in the drawings). 
     The support beam  62  may be made of stainless steel pipe and is wrapped by the reinforced grill mesh or geogrid  61 . The reinforced grill mesh or geogrid  61  wraps around the support beam  62  and is overlapped and engaged with another reinforced grill mesh or geogrid  61  by clip devices  65 . 
     The rope  63  may be made of a steel cable to wind around the support beam  62  and the strut  72  for anchoring the reinforced grill mesh or geogrid  61 . The rope  63  may be slid on the strut  72  up or down without breaking away. 
     The clamp means  64  clamps and fastens two free ends of the rope  63  after winding around the support beam  62  and strut  72  so that the reinforced grill mesh or geogrid  61  will be harnessed by the strut  72  without slipping away. 
     During construction of one layer of the reinforced retaining wall  6 , lay the reinforced grill mesh or geogrid  61  on the work site  1 , then lay and pile up sacks of retaining earth (not shown in the drawings) on the reinforced grill mesh or geogrid  61  and compact to desired density. Then wind the reinforced grill mesh or geogrid  61  around the support beam  62  to couple with another layer of reinforced grill mesh or geogrid  61  through the clip devices  65 . Then wind the rope  63  around the support beam  62  and strut  72 , and clamp the rope  63  at the two free ends thereof by the clamp means  64  to complete the installation of the reinforced retaining wall  6 . 
     As the rope  63  may be slid up or down on the strut  72  according geographical conditions, the fastening means may be free from stress concentration resulting from settlement of foundation or sagging of the reinforced materials. 
     Furthermore, the fastening means  7  can integrate the soil nailing  2  and reinforced retaining wall  6  to become one rigid body. Sliding at the interface between the two can be prevented from incurring. Construction thus can be done more rapidly to save time and work. Consumption of the soil nailing  2  can also be reduced, and the foundation width of the reinforced retaining wall  6  can also be decreased.