JP6324916B2 - Measures to improve long-term maintenance performance by reducing earthquake resistance and residual deformation of double-wall reinforced embankment method with large slenderness ratio - Google Patents

Description

  The present invention is a embankment construction method for greatly improving long-term maintenance management performance by reducing earthquake resistance and residual deformation of both ends reinforced embankment walls with a large slenderness ratio among reinforced embankment walls constructed in railways, roads, etc. It is about.

  In recent years, construction of reinforced embankments has been increasing in railway embankments and road embankment structures. In many cases, a geotextile (planar reinforcing material) is used as the reinforcing material in the reinforced embankment, but if the slope is steep, a wall work is required. There are many wall works in the form of wrapping sandbags and welded wire mesh with geotextiles, and wall works with small rigidity such as L-shaped expanded metal connected to geotextiles. Alternatively, there is also a divided type wall work in which blocks and divided panels are stacked. These wall surfaces are called divided wall surfaces.

  On the other hand, the wall surface in the form of wrapping the earthen wall or welded wire mesh with geotextile is used as the primary wall surface, and after the deformation of the reinforcing embankment has converged, it is constructed as the secondary wall surface. There is an RRR method having a “wall surface”. It has been clarified that the strength of the reinforced embankment is generally improved as the rigidity of the wall construction is higher if other conditions are the same.

  The RRR method is a method of constructing a rigid wall reinforced embankment with a steep or vertical slope using an integral wall surface with bending rigidity and a planar reinforcing material. Yes.

  In such a development, when the reinforced embankment wall method is adopted instead of the viaduct from the viewpoint of economic efficiency or from the viewpoint of effective use of tunnel excavated sand (tunnel), even in urban areas where there are many land restrictions There are many more. The reinforced embankment wall method used for such a purpose is often used in the form of a reinforced embankment wall with a so-called slenderness ratio and a long extension distance. In this case, because the embankment width is relatively small and the embankment height is a short columnar structure, when the wall height exceeds about 10 m, the long-term maintenance performance is improved by reducing earthquake resistance and residual deformation. Technology development is an urgent need. That is, as the ratio of the height to the width of the embankment-reinforced embankment wall (elongation ratio) is larger, the overturning / bending deformation in the cross section perpendicular to the extending direction becomes more prominent and the earthquake resistance is lowered. On the other hand, geosynthetic reinforced earth wall structure with rigid integral wall construction resists effectively. However, it is necessary to further improve stability in order to ensure stability against the level 2 ground motions experienced in the 1995 Hanshin-Awaji Earthquake and the 2011 Great East Japan Earthquake. At the same time, it is necessary to further improve the long-term maintenance performance by suppressing the long-term residual deformation that tends to be a problem as the wall height increases.

JP 2014-091915 A

Fumio Tatsuoka: Reinforced soil structure for restoration / reconstruction from the 2011 Great East Japan Earthquake. 13, August 2011 Geotechnical Society: Issues and Countermeasures for Ground Disasters during Earthquakes: Lessons and Recommendations for the 2011 Great East Japan Earthquake (First), July 2011 Nikkei Construction, pp. 34-43, 2011.10.20

  However, when a large earthquake such as L2 ground motion acts on both ends of the reinforced embankment wall, the function may be impaired due to excessive shear deformation or overturning failure. In other words, at this time, an excessive tensile force is applied to one vertical wall work and embankment of both ends reinforced embankment, and an excessive compressive force is applied to the other vertical wall work and embankment, respectively. May cause tensile failure, buckling failure in wall construction and compression failure of embankment.

  In view of the above situation, the present invention increases the rigidity of the structure of both ends reinforced embankment wall having a large slenderness ratio and suppresses long-term residual deformation even if a large earthquake such as L2 ground motion acts on both ends reinforced embankment walls. It is an object of the present invention to provide a method for improving the long-term maintenance performance by reducing the earthquake resistance and residual deformation of the double-walled reinforced embankment method with a large slenderness ratio that can maintain them.

In order to achieve the above object, the present invention provides
[1] In the measures for improving long-term maintenance performance by reducing the seismic resistance and residual deformation of the double-walled reinforced embankment method with a large slenderness ratio, the top- face work and the double-sided reinforced embankment covering the entire top edge of the double-walled reinforced wall By connecting the beam arranged in the length direction of the wall to the tie rod that penetrates the wall work at both ends and is anchored at the wall work work bottom end with the vertical tension material, The vertical tension material is fastened, and preload and prestress are vertically applied to the reinforcing embankment.

  [2] A beam disposed in the length direction of the both-end reinforced embankment wall in the method for improving long-term maintenance performance by reducing earthquake resistance and residual deformation of the both-end reinforced embankment wall method having a large slenderness ratio as described in [1] Are arranged with a predetermined interval.

  [3] In the measures for improving long-term maintenance performance by reducing the earthquake resistance and residual deformation of the double-end reinforced embankment wall method having a large slenderness ratio as described in [2] above, a beam disposed in the length direction of the double-wall reinforced embankment wall Has a predetermined interval of 5 m.

  [4] A beam arranged in the length direction of the both-end reinforced embankment wall in the method for improving long-term maintenance performance by reducing earthquake resistance and residual deformation of the both-end reinforced embankment wall method having a large slenderness ratio as described in [2] above The vertical tension material for embankment prestress and the vertical tension material for wall construction prestress are alternately arranged at both ends of the wall.

  [5] In the construction method for improving long-term maintenance performance by reducing the seismic resistance and residual deformation of the double-wall reinforced embankment method with a large slenderness ratio as described in [1] above, (a) constructing the foundation of the wall construction, (b) Remove and compact the soil layer, (c) build higher layers sequentially, (d) place the beams in the length direction of the embossed embankment wall on the top layer and tighten the vertical tension material to fill the embankment And (e) performing concrete placement on the retaining wall frame to complete the embankment.

  [6] In the method for improving long-term maintenance performance by reducing the seismic resistance and residual deformation of the double-end reinforced embankment method with a large slenderness ratio as described in [1] above, It is characterized by arranging a roadbed.

  [7] In the construction method for improving long-term maintenance performance by reducing the seismic resistance and residual deformation of the double-walled reinforced embankment method with a large slenderness ratio as described in [1] above, the depth and width of the foundation in order to prevent overturning failure It is characterized by increasing.

  [8] In the measures for improving long-term maintenance performance by reducing the seismic resistance and residual deformation of the double-wall reinforced embankment method with a large slenderness ratio as described in [1] above, the restraint pressure maintenance function during embankment compression and the suppression during embankment expansion It comprises a ratchet device that performs its function with a separate rod.

  [9] The prestress maintenance function device at the time of embankment compression is provided in the measures for improving long-term maintenance performance by reducing the earthquake resistance and residual deformation of the double-wall reinforced embankment wall construction method having a large slenderness ratio as described in [1] above. It is characterized by.

  [10] In the above-mentioned construction method for improving the long-term maintenance performance by reducing the seismic resistance and residual deformation of the double-walled reinforced embankment method with a large slenderness ratio as described in [1] above, a function device for suppressing the rise of the reaction beam during embankment compression is provided. It is characterized by doing.

According to the present invention, the following effects can be achieved.
(1) The overall structure of the embossed embankment wall having a large slenderness ratio increases the bending frequency by increasing the natural frequency f ₀ with respect to the bending vibration, and the bending vibration response is lowered, and the structure is increased by increasing the rigidity of the embankment. Bending deformation and shear deformation are suppressed, and the tensile strength of the wall construction and embankment and the compressive strength of the embankment are improved, so that the strength of the structure against overturning and bending failure is increased. With these effects, the seismic resistance and long-term maintenance performance as a structure are significantly improved.
(2) By using a beam (about 1 place in 5m) connected to the wall work of the embankment retaining wall on both ends, or using a concrete roadbed under a slab track, connect these to the wall work on both ends. It is possible to increase the rigidity of the reinforced embankment by preloading and prestressing the reinforced embankment vertically by a simple method such as taking a vertical reaction force and tightening a nut. As a result, the natural frequency f ₀ with respect to the bending vibration of the structure can be increased and maintained, and at the same time, the residual deformation of the embankment can be reduced.
(3) Cover the entire reinforced embankment with a concrete roadbed under the slab track, take vertical reaction force at both end wall works, and apply preload and prestress vertically to the reinforced embankment by simple methods such as tightening nuts. The tensile strength is exerted on the high-strength geosynthetic reinforcement material tightly bound to the outer rigid wall surface, so that the rigidity of the embankment is efficiently improved. As a result, the natural frequency f ₀ with respect to the bending deformation of the entire reinforced embankment is improved and the shear deformation is greatly suppressed. At the same time, the residual deformation of the embankment can be reduced. Since the embankment is reinforced with geosynthetics, the yield strength due to the compressive load generated in the embankment when the structure undergoes bending deformation is improved, and residual deformation is suppressed.
(4) By introducing compressive pre-stress into the wall work, the strength against the tensile load of the wall work is improved, so that the resistance force against the vertical tension of the foundation concrete part of the wall work can be used effectively, and the structure The stability against overturning and bending fracture is improved, and residual deformation is suppressed.
(5) As a result of the above, it becomes possible to make the wall height of the both-ends reinforced embankment wall having a long extension distance significantly higher than the embankment width.
(6) When the embankment height of the both-ends reinforced embankment wall can be increased, it becomes possible to effectively utilize tunnel excavation shears and the like as a embankment material. In particular, it is possible to effectively utilize materials that are soil-contaminated by natural sources as embankment materials by separately taking measures against pollution.

It is a schematic diagram of the destruction mode at the time of the big earthquake of the both-ends reinforced embankment wall which concerns on this invention. It is a cross-sectional schematic diagram of the beam form of the both-ends reinforcement embankment body with a large slenderness ratio which shows 1st Example of this invention. It is a plane schematic diagram of the beam form of the both ends reinforcement embankment with a large slenderness ratio which shows 1st Example of this invention. It is a figure which shows the concrete construction procedure which implemented the construction method of the both-ends reinforcement embankment body with a large slenderness ratio of this invention by the beam form. It is a figure which shows the example applied to the concrete roadbed under the slab track of the both ends reinforcement embankment body with a large slenderness ratio which shows 2nd Example of this invention. It is a schematic diagram of the deformation / stress situation at the time of earthquake of both ends reinforced embankment wall. It is a figure which shows the conventional wall surface construction penetration condition. It is a figure which shows the example which made the rooting depth and width | variety of the base part larger than the conventional method shown in FIG. It is a figure which shows the conventional method in the case of the slab track | orbit on a typical both-ends reinforcement embankment. It is a schematic diagram of the ratchet device for demonstrating the maintenance function of the restraint pressure at the time of embankment compression, and the raise suppression function of the reaction beam at the time of embankment expansion using two different rods, respectively. It is a figure which shows the maintenance function apparatus of the prestress (restraint pressure) at the time of embankment settlement (compression). It is a figure which shows the raise suppression function apparatus of the reaction beam at the time of embankment expansion.

The improvement method of long-term maintenance and management performance by seismic resistance and residual deformation reduction of the double-sided reinforced embankment method with a large slenderness ratio of the present invention is a top-end surface method that covers the entire top end of the double-sided reinforced embankment wall and a double-sided reinforced embankment By connecting the beam arranged in the length direction of the wall to the tie rod that penetrates the wall work at both ends and is anchored at the wall work work bottom end with the vertical tension material, The vertical tension material is fastened and preloaded and prestressed vertically on the reinforced embankment.

  Hereinafter, embodiments of the present invention will be described in detail.

  FIG. 1 is a schematic view of a failure mode in a large earthquake of a double-sided reinforced embankment according to the present invention.

As shown in this figure, when a large earthquake such as L2 ground motion acts on both-end reinforced embankment walls, the function is impaired due to excessive shear deformation or overturning failure. At this time, an excessive tensile force 103 is applied to one vertical wall work (vertical wall work) 101 and the embankment 102 of both ends reinforced embankment, and an excessive tension force 103 is applied to the other vertical wall work (vertical wall work) 104 and the embankment 105. The compressive force 106 acts, and tensile failure occurs in the wall surface work and embankment, and buckling failure and embankment compression failure occur in the wall surface work, respectively. Here, 107 is a top end face work, B is the embankment width of the both-ends reinforced embankment wall, and H is the height of both-ends reinforced embankment.

  In addition, when the embankment becomes higher, residual deformation such as settlement of the embankment over a long period of time becomes larger, and the usability of the embankment may be significantly reduced.

As these countermeasures, the following methods function effectively.
(1) A structure with a large slenderness ratio may lose its function as a structure due to overturning, bending fracture, or excessive shear deformation during a large earthquake. Therefore, seismic stability is improved by keeping the natural frequency f ₀ for bending and shear vibrations large as a whole structure, keeping the response to earthquake motion small and suppressing bending and shear deformation, and increasing the resistance to overturn and bending shear failure. To improve. At the same time, the long-term maintenance performance of the embankment is improved by improving the rigidity of the embankment and reducing the residual deformation.
(2) Reinforced embankment with a simple method such as installing beams (about 1 place in 5m) connected to the wall work of both-ends reinforced embankment retaining wall, taking vertical reaction force at both wall works, and tightening nuts. Applying pre-load vertically to the body to make it elastic and then applying pre-stress makes the reinforced embankment more rigid and reduces residual deformability.
(3) By making the high-strength geosynthetic reinforcement connected to the wall surface work efficiently and exhibiting tensile resistance, a large vertical load is applied without destroying the embankment. Efficiently realize high rigidity of embankment. As a result, the natural frequency f ₀ with respect to the bending deformation of the entire reinforced embankment is greatly improved, and a decrease in f ₀ due to a decrease in rigidity due to strong ground motion can be suppressed. At the same time, bending deformation and shear deformation are greatly suppressed. The embankment is reinforced with geosynthetics, and at the same time, it prevents the occurrence of compressive failure due to the vertical load that increases during bending deformation, and suppresses residual deformability.
(4) At the same time, the tensile failure due to the vertical tensile force is less likely to occur. Moreover, the compressive prestress is applied to the wall surface work in the vertical direction, thereby improving the strength of the wall work against tensile fracture. With this and the functions (2) and (3) above, the yield strength against overturning and bending breakage of the double-sided reinforced embankment retaining wall is improved.
(5) In the L2 ground motion where the maximum horizontal acceleration is close to 1 g (Earth's acceleration), in the double-sided reinforced embankment where the slenderness ratio H / B> 1/3, the fall displacement due to the lifting of the edge is When H / B> 1, tipping destruction becomes a problem. Therefore, in addition to improving the resistance to tensile failure of the wall work and embankment, in order to add an anchor function to the foundation concrete part of the wall work, the foundation concrete part is deepened, and the width is increased as necessary.
(6) In order to preload and prestress the entire reinforced embankment and apply compressive prestress to the wall work, a method of connecting the concrete roadbed under the slab track with the wall work of the reinforced embankment retaining wall on both ends is adopted. By doing so, it becomes high rigidity with respect to the bending deformation and shear deformation of the reinforced embankment, and the proof strength against overturning and bending failure is increased.
(7) As a device for maintaining the pre-stress, the stability of the embankment is achieved by using a ratchet device that exerts a restraining pressure maintaining function at the time of embankment compression and a suppression function at the time of embankment expansion using two different rods. Plan
(8) That is, the reaction beam for converting the tie rod tension into the vertical restraint force on the embankment sinks with the compressive deformation of the embankment, but does not rise with respect to the expansion of the embankment. As a result, the vertical force applied to the embankment increases. That is, the restraint pressure acting on the embankment is increased, and the embankment can be kept stable.
(9) Prestress (restraint pressure) maintenance function device at the time of embankment settlement (compression) is a device that applies a vertical compression force to the embankment with a certain amount of stroke and using a spring with a certain degree of rigidity. The reaction beam rise restraint device is a threaded rod with a bolt that is always going to rotate with a spring, etc., so that when the embankment sinks, the reaction beam will not rise freely. Device.
(10) In order to increase the rigidity of the reinforced embankment, cement-impregnated gravel soil is sandwiched or rolled out and rolled as necessary for constructing the reinforced embankment.

  FIG. 2 is a schematic cross-sectional view of a beam form of a double-end reinforced embankment having a large slenderness ratio according to the first embodiment of the present invention, and FIG. 3 is a schematic plan view of a beam form of the double-end reinforced embankment wall body.

In these figures, 1 is the ground, 2 is a reinforced embankment, 3 is a geotextile, 4 is a high-strength geotextile, 5 is a retaining wall frame (both ends reinforced embankment wall) , 6 is a beam, 7 is a vertical tension material (embankment prestress ), 7 'is a vertical tension material (for pre-stressing on the wall surface), 8 is a cement-improved gravel layer (sandwich or all layers), 9 is a sandbag or welded wire mesh, 10 is foundation concrete, 11 is a fixture , 12 is a vinyl chloride pipe, 15 is a compressible member , and 16 is a top face work .

Here, the vertical prestressing material 7 for embankment prestress and the vertical stressing material 7 'for wall surface prestressing are alternately arranged in the longitudinal direction (Y direction) of the structure. (Refer to FIGS. 10 to 12 for the structural form of the vertical tension material 7 for embankment prestress)
Thus, the construction method of the both-ends reinforced embankment with a large slenderness ratio of the present invention was carried out in a beam form.

  Hereinafter, a specific construction procedure will be described.

  FIG. 4 is a diagram showing a specific construction procedure in which the method for constructing a double-end reinforced embankment with a large slenderness ratio according to the present invention is implemented in a beam form.

  First, as shown in FIG. 4A, the foundation of the wall surface construction is constructed. The basic concrete wall frame reinforcing bar may be changed from the one used for a normal reinforcing earth retaining wall to a large-diameter reinforcing bar having a predetermined tensile strength, and this may also be used. As the vertical tension material 7, a material having a predetermined tensile strength is used.

Next, as shown in FIG. 4 (b) ~ FIG 4 (c), build one layer at a time of reinforcing embankment body 2 on the ground 1. At that time, a horizontal tensile reinforcing material 3 such as a normal strength geotextile is applied to the lower part of the reinforcing embankment 2, and a horizontal tensile reinforcing material such as a high strength geotextile 4 is applied to the upper part of the reinforcing embankment 2. However, it is installed in accordance with rolling and rolling pressure, and is rolled back to a crushed stone layer filled in a soil cave filled with crushed stone or a welded wire mesh 9 as a temporary restraint of the wall surface at both ends.

  When constructing this reinforced embankment body, in order to increase the rigidity of the reinforced embankment body, a cement improved gravel soil layer 8 is sandwiched as a embankment material for constructing the reinforced embankment body if necessary, or is spread over the entire layer. Take out and roll.

  This operation is repeated, and as shown in FIG. 4D, a reinforced embankment body is constructed to a predetermined embankment height, and a beam 6 (convex shape) is constructed thereon. The beam 6 is previously punched with a vinyl chloride pipe or the like so that the vertical tension member 7 can penetrate. Here, only one side is shown, but both sides have the same construction.

  In order to increase the rigidity of the entire embankment, the reinforced embankment uses a cement-modified gravel soil 8 in a sandwich shape or in all layers.

  After constructing the beam 6, a tensile force is applied to the vertical tension member 7 with a nut or the like, and a preload is applied to the reinforced embankment 2 for a certain period. After reaching the steady state where the progress of creep deformation of the embankment has been stopped by preloading, a part of the preloading load is released and a certain load is set as prestress. It should be noted that a load cell is previously installed in the fixing jig 11 that applies a tensile force to the vertical tension member 7 for prestress management. This load cell is made replaceable.

  Finally, as shown in FIG. 4 (e), after the settlement and deformation of the foundation ground 1 and the reinforcing embankment 2 are completed, the concrete of the retaining wall frame 5 is placed in the original position. At that time, the compressibility is high between the lower surface of the beam 6 and the upper end of the wall surface so that the prestress applied to the embankment is not reduced by the beam being supported by the upper end of the wall surface by compression of the future embankment. Insert a durable compressible member 15.

  As the compressible member 15, a sheet made of a special EVA (ethylene vinyl acetate copolymer) resin having a three-layer structure may be used.

  In addition, about the vertical tension material 7 which prestresses embankment, the method by the ratchet apparatus for maintaining the preload and prestress with respect to the long-term creep deformation of the both ends reinforcement embankment body mentioned later, and the bending and shear deformation at the time of an earthquake Please refer to.

  Next, an example in which the second embodiment of the present invention is applied to a concrete roadbed under a slab track of a double-end reinforced embankment with a large slenderness ratio will be described.

  FIG. 5 is a diagram showing an example in which the second embodiment of the present invention is applied to a concrete roadbed under a slab track of a double-end reinforced embankment with a large slenderness ratio.

  After completing the reinforced embankment constructed by the construction procedure as described above, the concrete roadbed (convex shape) 13 under the slab track is constructed thereon. The concrete roadbed 13 is punched in advance with a vinyl chloride pipe or the like so that the vertical tension member 7 or the frame reinforcing bars of the both-end retaining walls (thickness changed) can penetrate. In addition, 14 is a vertical wall and 15 is a compressible member.

  Thereafter, as in the case of the beam described above, a tensile force is applied to the vertical tension member 7 with a nut or the like, and a preload is applied to the reinforced embankment 2 for a certain period. After reaching a steady state where the progress of creep deformation of the embankment has been stopped by preloading, a part of the preloading load is released and a certain load is applied as prestress.

  Finally, after the settlement and deformation of the foundation ground 1 and the reinforcing embankment 2 are completed, the concrete of the retaining wall frame 5 is placed in the original position, and the vertical wall 14 is further constructed on the concrete roadbed.

  At that time, a highly compressible but durable compressible member 15 is inserted between the lower surface of the beam 6 and the upper end of the wall work in order to keep the reduction rate of the prestress due to the compression of the future embankment small. .

  Finally, vertical prestress is introduced into the wall surface by a normal method using the vertical tension member 7 'for wall surface prestressing as the wall surface.

  In addition, about the vertical tension material 7 which applies prestress to embankment, the vertical tension material for embankment prestress and the vertical tension material for wall construction prestress are the longitudinal direction of a structure similarly to the method shown in FIGS. Place them alternately. For the structure format, refer to FIGS. 10 to 12 described later and their descriptions.

  Next, a description will be given of a countermeasure method for the double-sided reinforced embankment so that the elongated ratio H / B> 1 according to the third embodiment of the present invention.

As mentioned above, as an earthquake resistance measure for both-end reinforced embankment walls, in order to increase the rigidity of the entire reinforced embankment and reduce the response displacement against excessive shear deformation that occurs during a large earthquake,
(1) Preload / stress is applied to the entire reinforced embankment.
(2) If necessary, use cement-improved gravel as embankment material.
(3) Integrate beams or concrete roadbed and vertical wall.

  In addition, for the tensile force acting on the vertical wall surface work, measures such as improving the resistance to tensile failure of the wall surface work by applying a compression prestress in the vertical direction to the wall surface work were adopted.

  However, when it is desired to increase the bank height H with respect to the bank width B, the slenderness ratio (H / B) is further increased, and further measures for preventing overturning are required. As a general guideline, in the case of a structure that satisfies H / B> 1, in order to add an anchor function to the foundation concrete part 10, the depth of insertion and the width are increased. It is necessary to further improve the seismic performance.

  When a large earthquake acts on a structure with a slenderness ratio H / B> 1, excessive tensile force (wall construction and embankment tensile failure and lifting of the entire structure), excessive bending / shear deformation occurs, The possibility of overturning is increased. In addition, an excessive compressive force (buckling occurs on the wall work and compressive fracture occurs on the embankment) acts.

  Fig. 6 is a schematic diagram of the deformation and stress status of the embankment-reinforced wall at the time of an earthquake. Fig. 7 is a diagram showing the conventional wall installation condition. Fig. 8 is a diagram of the foundation part than the conventional method shown in Fig. 7. It is a figure which shows the example which enlarged the penetration depth and width | variety.

In FIG. 6, 21 is an excessive tensile force (tension breakage of wall construction and embankment and lifting of the whole structure), 22 is an excessive bending / shear deformation, and the occurrence of this bending / shear deformation may cause a rollover failure. growing. 23 is an excessive compressive force (buckling failure occurs in the wall work), 24 is the ground surface, 25 is the top end face work, D is the depth of penetration (the necessary depth for normal use is 40 cm for D The following).

  As described above, the tensile failure of the embankment and the lifting of the entire structure occur.

  In FIG. 7, 30 is a ground surface, 31 is a wall construction intrusion part, 32 is leveled concrete, 33 is a base material, 34 is embankment, and a required penetration depth D = De + Do is 40 cm or less.

  The required penetration depth in the normal case is D ≧ 40 cm, and by increasing the penetration depth and width of the foundation, the passive resistance and anchor function of the penetration are greatly increased, as in L2 ground motion. Effectiveness against overturning failure of both-ends reinforced embankment predicted during a major earthquake.

  FIG. 9 is a diagram showing a conventional method in the case of a slab track on a typical both-end reinforced embankment. A resin foaming agent or joint material is installed on the reinforced embankment wall, and the concrete roadbed 41 is simply placed on the reinforced embankment wall. There was a problem with the stability of time.

  Next, a method using a ratchet device for maintaining preload / prestress against long-term creep deformation and bending / shear deformation at the time of earthquake will be described.

  The reinforced embankment sinks due to creep deformation and traffic load over a long period of time. In addition, when the compaction is loose, it will sink due to seismic load. Even in such a case, it is necessary to maintain the tension acting on the tie rod.

  On the other hand, during a large-scale earthquake, as shown in FIG. 6, shear deformation and bending deformation occur simultaneously in the double-end reinforced embankment with a large slenderness ratio. When shear deformation occurs, the reinforced embankment tends to expand due to dilatancy. Further, when subjected to bending deformation, one of the both-end reinforcing embankments tends to extend in the vertical direction. If the expansion of these embankments can be effectively constrained, the tension of the tie rods will increase and the vertical force applied to the embankments will increase when the embankments try to expand.

  By effectively utilizing these two functions, it is possible to maintain the stability of the both-end reinforced embankment during a large earthquake.

  FIG. 10 is a schematic diagram of a ratchet device for demonstrating the function of maintaining the vertical restraint pressure at the time of embankment compression and the function of suppressing the rise of the reaction beam at the time of embankment expansion using two different rods. In this figure, 51 is a reinforcing embankment, 52 is a reaction force beam, 53 is a function of maintaining restraint pressure when embankment is compressed (FIG. 11), and 54 is a function of suppressing the rise of reaction force beam when the embankment is expanded (FIG. 12). .

  Similarly, FIG. 11 is a diagram showing a prestress (restraint pressure) maintenance function device at the time of embankment settlement (shrinkage), and FIG. 12 is a diagram showing a reaction beam rise suppression function device at the time of embankment expansion.

  In FIG. 11, 61 is embankment, 62 is a reaction beam that converts tie rod tension into vertical restraint force on the embankment, 63 is a rod, 64 is washer, 65 is a reaction force plate screwed to the rod, and 66 is a stroke. There is a certain amount of rigidity, a certain degree of rigidity, and a spring that applies a vertical compressive force to the embankment.

  The prestress (restraint pressure) maintenance function device at the time of settlement (shrinkage) of the embankment is a device that applies a vertical compression force to the embankment by using a spring having a certain amount of stroke and a certain degree of rigidity.

  In FIG. 12, 71 is embankment, 72 is a reaction beam, 73 is a rod, 74 is a washer, 75 is a ball bearing for rotational displacement, 76 is a bolt to which rotation force is constantly applied by a spring or the like, When the embankment sinks, it rotates so that the reaction beam cannot rise freely. 77 is a spring or other device that applies a rotational force to the bolt, and 78 is a threaded rod.

  As shown in FIG. 12, the device for suppressing the rise of the reaction beam during expansion of the embankment is equipped with a bolt 76 which is always going to rotate with a spring 77 or the like on a threaded rod 78 and rotates when the embankment 71 sinks. Thus, the reaction beam 72 cannot be raised freely.

As mentioned above, according to the present invention,
(1) if increasing the rigidity of the entire structure of the slenderness ratio of the larger ends reinforcing embankments walls suppressed small decrease in the natural frequency f ₀ by keeping it, predominant frequency f during large earthquakes (strong ground motion) There is no resonance without approaching _p . As a result, the earthquake resistance of the both-ends reinforced embankment wall with a large slenderness ratio can be remarkably improved.

(2) When the natural frequency f ₀ of the entire structure of the double-walled reinforced embankment wall having a large slenderness ratio is reduced, the response displacement increases, and the risk of derailment increases in railways. On the other hand, if the natural frequency f ₀ of the entire structure can be maintained at a high value, the risk of derailment of a Shinkansen vehicle or the like can be reduced.

  (3) When the slenderness ratio of the double-sided reinforcement embankment increases, the overturning, bending, and shear deformation become prominent, and the vertical compressive force and the vertical tensile force acting on the wall work on both sides increase. By improving the proof strength against relatively small vertical tensile force of wall work, the resistance performance against overturning and bending / shear failure can be remarkably improved.

  (4) The horizontally disposed geosynthetic reinforcement and the vertical wall surfaces on both sides do not directly resist the shear deformation of the double-sided reinforced embankment wall structure. By stabilizing the embankment by exerting high tension on the high-strength geosynthetic reinforcement connected to the wall work, the entire embankment is elasticized by applying a high preload in the vertical direction and maintaining high prestress. Then, the restraint pressure in the embankment can be increased, and the rigidity of the embankment can be significantly increased. Thereby, the shear deformation of the structure can be effectively suppressed.

  (5) The structure is subjected to bending deformation and receives a vertical compressive force on one side and a vertical tensile force on the other side. The embankment is reinforced with geosynthetics reinforcement, which increases the resistance to vertical compression force, prestresses in the vertical direction, and restrains the expansion of the embankment in the vertical direction. Increases resistance to stretching in the direction. These functions can effectively suppress bending deformation of the structure.

  (6) As a result of greatly improving the earthquake resistance, it becomes possible to significantly increase the wall height of the double-sided reinforced embankment wall with an extended distance compared to the embankment width.

  In addition, this invention is not limited to the said Example, Based on the meaning of this invention, a various deformation | transformation is possible and these are not excluded from the scope of the present invention.

  The measures for improving long-term maintenance performance by reducing the seismic resistance and residual deformation of the double-end reinforced embankment method with a large slenderness ratio of the present invention is the slender ratio even if a large earthquake such as L2 earthquake motion acts on both-end reinforced embankment walls. Can increase the rigidity of the entire structure of the reinforced embankment wall with large both ends and maintain it, can suppress the long-term residual deformation, and the seismic resistance and residual deformation of the reinforced embankment wall method with large slenderness ratio It can be used as a countermeasure for improving long-term maintenance performance by mitigation.

1 Ground 2 Reinforced embankment 3 Geotextile 4 High-strength geotextile 5 Retaining wall frame (both ends reinforced embankment wall)
6 Beam 7 Vertical tension material (for embankment prestress)
7 'Vertical tension material (for wall construction prestress)
8 Cement improved gravel layer (sandwich or all layers)
9 Clay or welded wire mesh 10 Foundation concrete 11 Fixing jig 12 Vinyl chloride pipe 13 Concrete roadbed 14 Vertical wall 15 Compressible member
16, 25, 107 Top face work 101 One vertical wall work (vertical wall work)
102, 105 Embankment 103 Excessive tensile force 104 The other vertical wall construction (vertical wall construction)
106 Excessive compressive force B Embankment width H of both-ends reinforced embankment wall Height of both-ends reinforced embankment

Claims (10)

The top end work covering the entire top edge of the double-sided reinforcement embankment wall and the beam arranged in the length direction of the double-sided reinforcement embankment wall are anchored to the bottom end of the wall work by penetrating the both-end wall works by the vertical tension material. By connecting to the tie rod, the vertical reinforcement is taken at the lower end of the wall work on both ends, the vertical tension material is fastened, and the preload and prestress are applied vertically to the reinforcing embankment, and the both ends reinforcing embankment with a large slenderness ratio A countermeasure for improving long-term maintenance performance by reducing the earthquake resistance and residual deformation of the wall method.   In the method for improving long-term maintenance performance by reducing the seismic resistance and residual deformation of the double-end reinforced embankment method with a large slenderness ratio according to claim 1, the beams arranged in the length direction of the double-end reinforced embankment wall have a predetermined interval. A long-term maintenance performance improvement method by seismic resistance and residual deformation reduction of the double-walled reinforced embankment wall method with a large slenderness ratio, characterized by taking and arranging.   In the method for improving long-term maintenance performance by reducing the seismic resistance and residual deformation of the double-end reinforced embankment method with a large slenderness ratio according to claim 2, the beams arranged in the length direction of the double-end reinforced embankment wall have a predetermined interval. A long-term maintenance performance improvement construction method by seismic resistance and residual deformation reduction of the double-wall reinforced embankment wall construction method with a large slenderness ratio characterized by being 5 m.   In the measures for improving long-term maintenance management performance by reducing the seismic resistance and residual deformation of the double-wall reinforced embankment method with a large slenderness ratio according to claim 2, both ends of the beams arranged in the length direction of the double-wall reinforced embankment wall are Improvement of long-term maintenance performance by reducing seismic resistance and residual deformation of double-wall reinforced embankment method with large slenderness ratio, characterized by alternately placing vertical tension material for embankment prestress and vertical tension material for wall prestress Countermeasure method. In the measures for improving long-term maintenance performance by reducing earthquake resistance and residual deformation of both ends reinforced embankment wall construction method with a large slenderness ratio according to claim 1,
(A) Build the foundation of wall work,
(B) Remove and compact the soil layer,
(C) Build higher layers sequentially,
(D) A beam is arranged on the uppermost layer in the length direction of the embossed embankment wall, and a vertical tension member is fastened to construct the embankment.
(E) A method for improving long-term maintenance performance by reducing earthquake resistance and residual deformation of the double-walled reinforced embankment method with a large slenderness ratio, characterized in that concrete is placed in the retaining wall frame to complete the embankment.   In the construction method for improving long-term maintenance performance by reducing earthquake resistance and residual deformation of the double-end reinforced embankment wall method with a large slenderness ratio according to claim 1, a concrete roadbed under a slab track is disposed at the top end of the double-wall reinforced embankment wall A long-term maintenance performance improvement method by reducing earthquake resistance and residual deformation of the double-walled reinforced embankment method with a large slenderness ratio.   In the construction method for improving long-term maintenance performance by reducing the seismic resistance and residual deformation of the double-wall reinforced embankment method with a large slenderness ratio according to claim 1, increasing the depth and width of the foundation in order to prevent overturning failure A long-term maintenance performance improvement construction method by seismic resistance and residual deformation reduction of the double-wall reinforced embankment wall method with a large slenderness ratio.   In the measures for improving long-term maintenance performance by reducing earthquake resistance and residual deformation of the double-wall reinforced embankment wall construction method with a large slenderness ratio according to claim 1, the restraint pressure maintenance function during embankment compression and the suppression function during embankment expansion are separately provided A long-term maintenance management improvement method by seismic resistance and reduction of residual deformation of a double-wall reinforced embankment method with a large slenderness ratio, which is equipped with a ratchet device that can be exhibited by a rod of the same type.   The improvement method of long-term maintenance management performance by seismic resistance and residual deformation reduction of the double-end reinforced embankment wall construction method with a large slenderness ratio according to claim 1, comprising a pre-stress maintenance function device at the time of embankment pressure shrinkage A long-term maintenance management method that improves the long-term maintenance performance by reducing the residual deformation and seismic resistance of the double-wall reinforced embankment method with a large slenderness ratio.   In the countermeasure method for improving long-term maintenance performance by reducing the seismic resistance and residual deformation of the double-end reinforced embankment wall construction method having a large slenderness ratio according to claim 1, it is provided with a function device for suppressing the rise of the reaction beam during embankment compression. Measures to improve long-term maintenance performance by reducing earthquake resistance and residual deformation of the double-walled reinforced embankment method with a large slenderness ratio.

Images