JP2007239202A - Aseismatic reinforcing structure of trough filling banking part - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aseismatic reinforcing structure for preventing a landslide-like slope variation and sliding falling-in of the whole trough filling banking part having a banking slope face in an earthquake. <P>SOLUTION: A division wall 2 is formed in banking in the trough part direction in the trough filling banking part 1 having the banking slope face 6. The division wall 2 is formed in a plurality of rows at a predetermined interval in the direction orthogonal to the trough part direction. The division wall 2 is formed by adding and hardening a cement-based solidifying material or a lime-based solidifying material to and in the banking. In a cross section in the direction orthogonal to the trough part direction of the trough filling banking part 1, an individual width of the banking part 1 is set small; the ratio of the length of a side surface (the natural ground and the division wall) contacting with the banking is enhanced; shearing resistance force of the whole banking part is increased; and deformation and sliding of the trough filling banking part are effectively prevented. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a seismic reinforcement structure in a valley-filled embankment such as in a large-scale residential land development site.

  In recent years, ground disasters in large-scale residential areas have been seen as a problem. Both the Great Hanshin-Awaji Earthquake in 1995 and the Chuetsu Earthquake in Niigata Prefecture in 2004 have caused problems such as landslide slope changes and sliding collapses in the whole embankment in the valley-filled embankment.

  Many large-scale residential areas have been created by combining cutting and embankment on sloped ground at a time when there is relatively little seismic activity. Unlike the so-called steeply sloped land, such a valley-filled embankment site is relatively flat and loosely sloped, so it does not appear to be a seemingly dangerous land. However, there are concerns about the occurrence of large-scale earthquakes, and such valley-filled embankments have existed throughout the country, and there is a need for countermeasures.

  So far, as a seismic structure of the embankment, in general, in order to remove the earth and sand with low shear strength near the surface of the natural ground and to improve the familiarity between the embankment and the natural ground, so-called step cutting is performed, and the horizontal layer is Rolling is performed to ensure the uniformity and compaction of the embankment near the boundary surface.

In addition to this, for example, the one described in Patent Document 1 below has a high tensile strength between the embankments, a so-called geotextile reinforcing material, and a block body connected to the reinforcing material on the side of the embankment. It is comprised so that it may be located and a retaining wall may be formed.
JP-A-2-167926

  In the step cutting, although some earthquake resistance is recognized, there is a problem that sufficient deformation restraint of embankment cannot be expected. Moreover, although it is recognized that the seismic structure of the embankment portion of Patent Document 1 is effective in the seismic resistance, the configuration is complicated because it constitutes a so-called geotextile reinforcing material or block body. There was a problem. Furthermore, there is a problem that it is not easy to apply the construction to the existing site.

  In the examination so far, some analyzes have been made as the cause of the landslide slope change and sliding collapse of the whole embankment in the valley filling embankment. As one of them, it is said that there is a decrease in the shear resistance of the embankment along the slip surface. It is said that the sliding force and displacement of the embankment caused by the earthquake motion are generated when the resistance force that becomes the limit along the slip surface becomes larger.

  The cause of the decrease in the shear resistance is, for example, the generation of saturated groundwater or excess pore water pressure accompanying an increase in the groundwater level. Therefore, lowering the groundwater level in the embankment is an effective means.

  The present invention is performed from a viewpoint different from the groundwater level, and in the embankment of the valley-filled embankment having a embankment slope, by forming a partition wall along the trough direction, The problem is to be solved by actively increasing the shear resistance of the embankment along.

  An object of the present invention is to provide an earthquake-resistant structure having a relatively simple configuration and improved stability against deformation and sliding in a valley-filled embankment.

  The seismic reinforcement structure of the valley filling embankment of the present invention has a configuration in which a partition wall is formed in the embankment along the valley direction in the valley filling embankment having a bank slope.

  In a preferred embodiment of the present invention, the partition wall is formed in a plurality of rows at a predetermined interval in a direction orthogonal to the valley direction.

  In a preferred embodiment of the present invention, the partition wall has a configuration in which a cement-based solidifying material is added to the embankment and hardened.

  Furthermore, in the preferable form of this invention, the said partition wall has comprised the structure which added and solidified the lime type solidification material to the embankment.

  According to the present invention, in the cross section in the direction perpendicular to the valley direction of the valley-filled embankment, the individual width of the embankment is made small, and the ratio of the lengths of the side surfaces (the ground and the partition wall) in contact with the embankment By raising and increasing the shear resistance of the whole embankment, it is possible to effectively prevent deformation and sliding of the embankment.

  Below, the partition wall as an earthquake-proof reinforcement structure of the embankment part which concerns on one Embodiment of this invention is demonstrated with reference to FIGS.

  FIG. 1 is a plan view of an embodiment of a partition wall as an earthquake-proof reinforcement structure for a valley-filled embankment having a embankment slope according to the present invention, and FIG. 2 is a cross-sectional view taken along line AA in FIGS. 3 is a cross-sectional view taken along line BB in FIG.

  The valley-filled embankment 1 is formed in a so-called valley where one side is open, surrounded on three sides by a natural mountain 7 such as a mountain or a hill. An embankment is formed on the ground line 4 inclined downward in the longitudinal direction of the trough while forming the open side of the trough with the embankment slope 6 and used for residential land or the like. Reference numeral 3 denotes a step cutting line, 5 denotes a creation plan line, and embankment is performed up to the creation plan line 5 to form the embankment portion 1. The embankment slope 6 of the construction plan line 5 is provided with a retaining wall on the frame, planting, or part of it, and a collapse prevention measure is taken. Reference numeral 2 denotes a partition wall formed inside the embankment according to the present embodiment. In the present embodiment, the partition wall 2 is formed along the longitudinal direction of the valley. However, when the width of the valley is wide, the partition wall 2 may not be the longitudinal direction. If the direction (longitudinal direction) toward the open side of the valley where the surface 6 is formed is the valley direction, the valley 6 is formed along this valley direction. The partition walls 2 are arranged in a plurality of rows at predetermined intervals in a direction perpendicular to the valley direction.

  The partition wall 2 is formed by, for example, adding cement-based solidified material or lime-based solidified material to the embankment and compacting. Or, by applying high-pressure jet agitation of slurry such as cement-based solidification material to the already-constructed embankment, or by agitation and mixing of mortar and embankment using a mixing processor Form. In particular, such high-pressure jet agitation and agitation mixing can also be applied to existing valley-filled embankments.

  The effect | action by the partition wall as an earthquake-proof reinforcement structure of the valley filling embankment which has the embankment slope formed in this way is demonstrated.

  It is said that the cross-sectional shape including the natural ground of the valley has an effect on the landslide slope change and sliding collapse at the time of the earthquake in the valley filling embankment. Specifically, it is known that it is particularly likely to occur when the ratio between the width of the valley where the embankment is performed and the depth of the embankment exceeds a certain value. In other words, when the width of the valley where the embankment is performed is larger than the depth of the embankment, these phenomena are likely to occur.

  The present invention forms a partition wall along the valley direction in the embankment of the valley-filled embankment having a embankment slope. By reducing the individual width of the section, increasing the ratio of the length of the side surface (the ground and the partition wall) in contact with the embankment, and increasing the shear resistance of the entire embankment section, the deformation and sliding of the valley-filled embankment section Effectively prevent.

  Next, one embodiment of construction for forming a partition wall as an earthquake-proof reinforcement structure for a valley-filled embankment having a embankment slope according to the present invention will be described with reference to FIGS.

  FIG. 4 is a schematic view showing a first stage of an embodiment of construction for forming a partition wall as a seismic reinforcement structure for a valley-filled embankment having a embankment slope according to the present invention, and FIG. It is a schematic diagram which shows the condition of the 2nd step of one Embodiment of the construction which forms the partition wall as a seismic reinforcement structure of the valley filling embankment which has the embankment slope which concerns on FIG. 6, FIG. 6 is the embankment slope which concerns on this invention FIG. 7 is a schematic view showing a third stage of an embodiment of construction for forming a partition wall as a seismic reinforcement structure for a valley-filled embankment having a valley, and FIG. 7 is a valley-filled embankment having a bank slope according to the present invention. FIG. 8 is a schematic diagram showing a fourth stage situation of an embodiment of construction for forming a partition wall as a seismic reinforcement structure for a section, and FIG. 8 is a seismic reinforcement structure for a valley-filled embankment having a bank slope according to the present invention. The situation after construction in one embodiment of construction to form a partition wall as It is to schematic diagrams.

  First, so-called step cutting is performed by removing earth and sand having low shear strength in the vicinity of the surface layer of the natural ground 7 along the inclined ground line 4. As the step height, a height of about 1.5 m can be normally assumed. After compacting the formed horizontal layer, the first embankment is performed (FIG. 4).

  Next, partition walls a are formed at predetermined intervals in the transverse direction width direction of the first embankment portion (FIG. 5).

  Similarly, the second embankment is performed (FIG. 6), and then connected to the previously formed partition wall a to form the partition wall b (FIG. 7). Finally, the partition wall 2 is formed in the embankment of the valley filling embankment 1 having an embankment slope along the trough direction. Then, the partition walls 2 are formed in a plurality of rows at predetermined intervals in a direction orthogonal to the valley direction (FIG. 8).

  In addition, the construction order demonstrated above is one embodiment to the last, and the method which does not depend on this construction order is also possible. In the above description, stepping is performed from the lower part in the downward inclination direction, and the construction is sequentially performed toward the upper part, but conversely, it is also possible to perform the construction from the upper part to the lower part sequentially. Also, only the embankment part is constructed first, and the already completed embankment part is subjected to high-pressure jet agitation of slurry such as cement-based solidification material, or mortar and embankment are mixed using a processing machine. It is also possible to form a partition wall as an earthquake-proof reinforcement structure for the embankment by performing agitation and solidification. In particular, according to such high-pressure jet agitation and agitation mixing, it can also be applied to existing valley-filled embankments.

The top view of one Embodiment of the partition wall as an earthquake-proof reinforcement structure of the valley filling embankment which has a embankment slope according to this invention AA sectional drawing of FIG. 1 and FIG. BB sectional drawing of FIG. The schematic diagram which shows the condition of the 1st step of one Embodiment of construction which forms the partition wall as a seismic reinforcement structure of the valley filling embankment which has a embankment slope according to this invention. The schematic diagram which shows the condition of the 2nd step of one Embodiment of the construction which forms the partition wall as an earthquake-proof reinforcement structure of the valley filling embankment which has the embankment slope according to this invention. The schematic diagram which shows the condition of the 3rd step of one Embodiment of construction which forms the partition wall as an earthquake-proof reinforcement structure of the valley filling embankment which has a embankment slope according to this invention. The schematic diagram which shows the condition of the 4th step of one Embodiment of construction which forms the partition wall as a seismic reinforcement structure of the valley filling embankment which has a embankment slope according to this invention. The schematic diagram which shows the condition after construction in one Embodiment of construction which forms the partition wall as an earthquake-proof reinforcement structure of the valley embankment embankment which has the embankment slope according to this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Embankment part 2 ... Partition wall 3 ... Step line 4 ... Ground line 5 ... Creation plan line 6 ... Embankment slope 7 ... Ground

Claims (4)

In the valley-filled embankment having a embankment slope, a partition wall was formed in the embankment along the valley direction.
Seismic reinforcement structure for valley-filled embankments.   The seismic reinforcement structure for a valley-filled embankment according to claim 1, wherein the partition walls are formed in a plurality of rows at a predetermined interval in a direction orthogonal to the valley direction.   The seismic reinforcement structure for a valley-filled embankment portion according to claim 1, wherein the partition wall is hardened by adding a cement-based solidifying material to the embankment.   The seismic reinforcement structure for a valley-filled embankment according to claim 1, wherein the partition wall is hardened by adding a lime-based solidified material to the embankment.

Images