JPS6234887B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for constructing an earth retaining wall on sloped ground such as a mountainous area.

When constructing roads, railways, etc. along the slopes of mountains, river cliffs, etc., and when creating various types of flat land such as industrial land and residential land, it is normal to construct areas higher than the planned ground. Excavate the mountain side and fill the lower valley side with earth to form a flat surface of the required width or area. Various earth retaining walls will be installed to ensure the stability of the cut and embankment slopes that will be formed at this time and to ensure the safety of the facility. Retaining walls installed on the cut side are relatively easy to install because the ground in front of the wall is a flat construction surface, but retaining walls installed on the embankment side have the base of the wall on sloping ground. Because of its location, it is not easy to secure a solid foundation ground surface with the width necessary to install the retaining wall, and as a result, the higher the wall height, the larger the retaining wall must be installed, which increases the construction cost. It will become bulky.

Conventionally, earth retaining walls installed on sloping ground take into consideration ground conditions from various types such as gravity walls, sloping walls (including stone masonry and block masonry), cantilever retaining walls, buttress retaining walls, etc. and choose.

On the other hand, in recent years, construction methods in which earth retaining walls are constructed using precast members made of concrete or steel have come into widespread use, and in order to reduce the thickness of the members and reduce the weight of the walls, the embankment that is backfilled is strengthened. Methods of construction that reduce the earth pressure caused by soil pressure, and methods of reinforcing the retaining wall by anchoring it to the ground behind it or installing a retaining wall to connect the retaining wall are being used.

However, in any of the above-mentioned conventional earth retaining walls, the retaining wall forming surface is vertical or slopes downward, and the supporting force and shear resistance in the vertical direction against the foundation supporting the retaining wall. It is stabilized by force to prevent it from tipping over and sliding sideways.

Next, regarding the expanded width of the road R located halfway up the sloped ground S, we will discuss the first to third embodiments using the conventional method.
Examples will be explained in detail with reference to FIGS. 1 to 3 in order. However, in the figure, W ₀ is the original width dimension of the road R, W ₁ is the widening dimension, and W is the width dimension after widening. In Fig. 2, Wa is the widening dimension on the embankment slope side, and Wb is the cut road width dimension. The required widening dimension on the side is (Wa+Wb).

Hereinafter, the side higher than road R (the right side when facing the figure) will be referred to as the mountain side, and the side lower than the road R (the left side when facing the figure) will be referred to as the valley side.

Now, in the first conventional embodiment shown in FIG. 1, in order to widen the road R only toward the valley side of the sloped ground S, embankment is carried out on the valley side until the widening dimension W ₁ is obtained. A technique is illustrated in which M is provided and a retaining wall Y is constructed below it. In this example, a slope M is provided and the embankment is carried out until the total widening dimension W ₁ is obtained, so a large amount of embankment is required and a large-scale retaining wall Y is required.

Moreover, the above-mentioned retaining wall Y is constructed vertically, and the rear earth pressure generates a vertical partial pressure F ₁ and a horizontal component force F ₂ , and this horizontal component force F ₂ tends to cause the retaining wall Y to topple over. In order to do this, the retaining wall Y is formed into a substantially L-shape with a horizontal flat base B integrally provided at the lower end. Therefore, construction of the retaining wall Y requires large-scale ground excavation, which requires a large amount of construction cost and construction time.

In addition, in the second conventional embodiment shown in FIG. 2, the total widening dimension is obtained by widening the road R by a dimension Wa toward the valley side and by a dimension Wb toward the mountain side. be.

Therefore, in this example, compared to the first embodiment, the amount of embankment on the valley side can be made approximately Wa/W ₁ , and the slope M ₁ can be shortened, and the retaining wall Y ₁ can also be made similar to that of the first embodiment. Although it can be made smaller than wall Y,
On the mountain side, it is necessary to perform cutting C until the widening dimension Wb is obtained and then construct a retaining wall _Y2 . In this example, the retaining wall _Y1 is the retaining wall Y of the first embodiment described above.
It was constructed in the same manner as the retaining wall Y2, and the retaining wall _Y2 is sloped forward to prevent it from falling over.

In addition, in the conventional third embodiment shown in Fig. 3, embankment is performed to widen the width only toward the valley side, but retaining wall Y ₃ is built sequentially without forming a slope against the embankment. It is constructed in an inclined manner.
Therefore, in order to construct the retaining wall _Y3 , a large amount of cutting earth _C1 is required, and the retaining wall _Y3 has to be large-scale.

That is, in the conventional method, in order to create a flat area such as a road on the ground surface of a steep slope, as shown in the examples shown in Figures 1 to 3, it is necessary to form a long embankment or cut slope, or to create a long slope. This resulted in the installation of a retaining wall, which had the disadvantage of increasing construction costs and land requirements.

In view of the drawbacks of the conventional methods described above, the present invention enables the construction of an earth retaining wall easily on sloping ground without performing large-scale excavation, and supports the load of the earth retaining wall body in a direction perpendicular to the sloping ground. This method prevents the earth retaining wall body from sliding sideways along the sloped ground, and actively prevents the earth retaining wall body from falling over to construct a safe and stable earth retaining wall in a short period of time and economically. The purpose of this invention is to provide a method of constructing an earth retaining wall that can contribute to the preservation of the natural environment.

In the earth retaining wall construction method according to the present invention, a supporting ground is formed to support the earth retaining wall body at the site where the earth retaining wall body is to be constructed, and a retaining wall is formed at the back portion of the earth retaining wall body. A retaining portion consisting of support piles, lock anchors, etc. is formed, and the earth retaining wall body is configured on the supporting ground in a reverse slope so that the load of the earth retaining wall body is applied to the supporting ground in a vertical direction. The earth retaining wall is constructed by connecting the earth retaining wall body to the retaining part through a retaining member made of cables, etc., and filling the back side of the earth retaining wall body to a required height.

Hereinafter, embodiments of the method of the present invention will be described based on the drawings.

First, the earth retaining wall body (hereinafter simply referred to as the body).
Three embodiments regarding the longitudinal cross-sectional shape of will be explained with reference to FIGS. 4 to 6.

FIG. 4 shows that the wall surface 2 of the main body 1 is formed by a combination of a vertical surface portion 3 and a circular arc surface portion 4.
The lower end portion 8 is perpendicularly in contact with the support ground surface 9, and is connected to a bracing portion to be described later by an upper cable 11 and a lower cable 12 as a bracing member, respectively, at a boundary point 10 of the above-mentioned double-sided portions and the lower end portion 8. Indicates when you are nervous. Note that 43 indicates the center point of the arc of the arc surface portion 4, 7 indicates the wall top of the main body 1, and 23 indicates the flat surface created by the back embankment 20.

In FIG. 5, the wall surface 2 of the main body 1 is formed from a vertical surface section 3, an arcuate surface section 4, and a lower surface section 5. 3 and the arcuate surface portion 4, and the lower end portion 8 are connected to the retaining portion by an upper cable 11 and a lower cable 12, respectively.

6 is similar to FIG. 4 and 5 except that the wall surface 2 of the main body 1 is formed from a vertical surface portion 3 and a paraboloid surface portion 6.
A case in which the configuration is similar to that shown in the figure is shown.

Now, as shown in these three examples, in the earth retaining wall according to the method of the present invention, the base surface of the lower end of the main body 1 is perpendicular to the supporting ground surface 9 at a position retreated backward from the vertical plane passing through the wall top 7 of the main body 1. The wall surface 2 is a combination of various surface shapes such as a face, an arcuate surface, and a paraboloid. Therefore, the selection of the combination of wall shapes depends on the height of the retaining wall, the degree of inclination of the supporting ground, the position of the retaining part, and the lower cable 1 described later.
This is done so that a highly stable and inexpensive earth retaining wall is installed that has an appropriate shape for the position of the direction change point, etc. of No. 2.

Next, a method for constructing an earth retaining wall according to the present invention will be specifically explained using an example of a structure using precast concrete members shown in FIGS. 7 to 16.

In the figure, 13 is an upper panel forming a vertical surface part at the upper part of main body 1, 14 is an intermediate panel forming an intermediate circular arc part at the center part of main body 1, and 15 is a lower panel forming a lower circular arc part at the lower part of main body 1. As shown in FIG. 9, these panels are stacked in a so-called staggered pattern, and are fastened vertically by PC steel bars 32, which will be described later, and are connected to the upper cable 11 and the lower cable 12. It is connected to the retainer section 17 by.

Hereinafter, each member will be explained in detail. The upper panel 13 is formed into a rectangular flat plate shape as shown in FIG. Two vertical stiffening ribs 26, 26 are provided to protrude in the vertical direction, and
The horizontal stiffening rib 27 is the vertical stiffening rib 2.
6 and 26 in a protruding manner. Moreover, a square-shaped fastening hole 28 is provided at the intersection of the vertical stiffening rib 26 and the horizontal stiffening rib 27 for inserting the upper cable 11 and fastening its end. The rigid ribs 26 are each provided with two insertion holes 31 for inserting the PC steel rods 32 therethrough, and the vertical stiffening ribs 26 have the above-mentioned holes at both upper and lower ends.
A locking part 30 in the shape of a rectangular cutout for locking and fastening the end of the PC steel rod 32 is provided with upper and lower openings.

Further, the upper panel 13 has a planar upper end surface 33 formed at its upper end, and a lower joining surface 35 for joining a lower adjacent panel at its lower end in a half-shaped manner.

Also, on the left and right end surfaces of the upper panel 13, there are side joint surfaces 3 for joining with laterally adjacent panels.
6 and 36 are formed in a point-symmetrical phase-cutting shape.

Next, the middle panel 14 is the upper panel 13 described above.
It is formed in the shape of a rectangular flat plate having the same size as , and is curved in a convex arc shape toward its surface 24A, that is, toward the left side in FIG. Also, on the surface 24A, there are two symmetrical vertical stiffening ribs 26A, 26A.
protrudes vertically. Moreover, the stiffening ribs 26A, 26A are formed in the same manner as the upper panel 13.
It has a PC steel bar locking part 30 and a PC steel bar insertion hole 31. Also, the middle panel 14 is replaced by the upper panel 13.
The stiffening ribs 26A, 26A are formed so that when stacked in a staggered manner between the upper panel 13 and the lower panel 15, the stiffening ribs 26A, 26A are located on the downward extension line of the vertical stiffening rib 26 of the upper panel 13. Further, the intermediate panel 14 is provided with a half-shaped upper joint surface 34 that engages with the lower joint surface 35 of the upper panel 13 on its upper surface, and side joint surfaces 36A having the same shape as the upper panel 13 on both left and right end surfaces. Equipped with 36A.

Next, the lower panel 15 that constitutes the lower arc surface part
The same shape as the intermediate panel 14 is applied, but the lower fastening hole of the PC steel rod 32 is not provided, the lower end joint surface is not a phase cutout, but a face, and as described later, the base during construction A mounting bolt for a temporary stiffening diagonal member 39 is attached to supplement the rigid connection with the panel 16.

Now, the upper panel 13 formed as above
The intermediate panel 14, the lower panel 15, and the base panel 16, which will be described later, are integrally fastened together via a PC steel rod 32 inserted into a PC steel rod insertion hole 31 of each panel. Moreover, the middle panel 14 and the lower panel 15
is formed along an arc centered on a center point 43 (shown in FIG. 7) on the sloped ground S.

Next, 16 is a base panel that is installed along the slope of the earth retaining wall construction to form the base of the earth retaining wall body, and as shown in Figure 12, it is formed into a rectangular flat shape and its The lower joint surface of the lower panel 15 is engaged with the upper surface of the lower panel 1.
5 is provided with an engagement groove 37 for orthogonally supporting the lower part of the member 5.

Further, inside the base panel 16, two cable insertion holes 29, 29 are provided through which the lower cable 12 for pulling the base panel 16 upwardly along the earth retaining wall construction slope is inserted. A fastening hole 28 for fastening the end of the lower cable 12 is recessed in one end (lower end as viewed in FIG. 12).

Furthermore, the base panel 16 includes the above-mentioned upper panel 13, intermediate panel 14, lower panel 15, etc.
An insertion hole 31A for inserting and fastening the lower end of the PC steel rod 32 inserted into the PC steel rod insertion hole 31 is provided outside the joining groove 37.

Next, reference numeral 17 shown in FIGS. 7 and 8 is a retaining portion formed in the shape of a buttress against the ground at the upper part of the sloped ground on which the earth retaining wall is constructed, and the fastening hole 28 between the retaining portion 17 and the upper panel 13 The upper cable 11 is stretched horizontally between the upper cable 11 and the lower cable 1 between the retaining part 17 and the fastening hole 28 of the base panel 16.
2 is stretched. However, the lower cable 1
2 is an intermediate support 1 fixed to the upper end of the sloped ground
At 8, the direction is changed and stretched in the shape of a letter.

Next, a construction example of constructing an earth retaining wall using each member configured as described above will be specifically explained with reference to FIGS. 13 to 16. First, the ground is shaped so that the retaining portion 17, the intermediate support stand 18, and the foundation work 19 for supporting the main body can be placed in predetermined positions, and that the tension arrangement of the upper cable 11 and the lower cable 12 is not hindered. . The retaining portion 17 is made of cast-in-place reinforced concrete, and its size and penetration depth are determined by examining the strength of the ground so as to have sufficient horizontal tensile resistance. If the ground strength is low, consider reinforcing it with lock anchors or using other types of restraints, such as support piles. The intermediate support 18 is also made of cast-in-place reinforced concrete and placed on the ground having the required strength. The shape of the foundation work 19 differs depending on the strength of the ground, but in the case of hard ground, it is sufficient to smooth the ground surface with concrete.

When the above-mentioned cast-in-place concrete construction is completed, the lower panel 15 and base panel 16 are assembled in advance.
A member integrated with the PC steel rods 32 and temporary stiffening diagonal members 39 is installed at a predetermined position on the foundation work 19 using a crane. Since the surface of the foundation 19 is steeply sloped, the panel is fixed with temporary fixing bolts 40 to prevent it from sliding, and the lower cable 12 is passed through the cable insertion hole 29 of the base panel 16 and the corresponding insertion hole of the retaining part 17 at both ends. The agreement will be tentatively concluded. Lower cable 1
It is preferable to perform the tension in step 2 by placing a turnbuckle in the middle. Now, after the lower panels 15 to 15 adjacent to each other on both left and right sides are successively joined and the lower panels are installed continuously, back embankment is carried out up to the primary embankment surface 38 shown in FIG. 13. The purpose of embanking to the height shown in the figure is to install the intermediate panel 14 and the upper panel 13 to resist the overturning force of the main body that occurs when the upper cable 11 is placed. The middle panel 14 is staggered with respect to the lower panel 15, that is, it is laterally shifted by half the panel width,
The upper panel 13 is stacked so as to be shifted laterally by half the panel width with respect to the middle panel 14, so that the panels are integrated in the lateral direction. The manner in which the panels are joined is shown in FIGS. 8 and 9. However, 25 in the figure indicates a panel joining line.

When each panel is stacked, the PC steel rod 32 is passed through the insertion hole, and the PC steel rod of the lower panel is connected to the coupler 44 by the coupler 44, and the panels are tension-fastened through the upper fastening hole (see FIG. 15). The upper cable 11 is loosely fastened so as not to overturn the main body, and as the back embankment progresses, it is tensed by the turnbuckles so that the main body maintains a predetermined shape.

In Figures 14 and 15, 41 is a PC
A nut for fastening the steel rod, 42 a nut for fastening the cable, and 44 a turnbuckle-shaped coupler.

It is clear from the above description that the method of the present invention can be applied not only to the precast concrete members disclosed in the above-mentioned embodiments but also to structures made of cast-in-place concrete and structures made of steel shapes and steel plates. .
There are various methods other than those described above for temporary construction methods, that is, methods for holding the earth retaining wall body so that it does not fall during construction, and these methods can be easily solved using known construction techniques. can.

There are remarkable effects that can be produced by applying the earth retaining wall of the present invention to road construction on sloping ground, but as an example, the case where the earth retaining wall of the present invention is applied to road widening shown in Fig. 16 is as follows. If you compare and contrast with the conventional examples shown in Figures 1, 2, and 3, it will be clear at first glance that it is possible to avoid the formation of long slopes and the construction of huge earth retaining walls, and it is possible to avoid roads of the same width. Even when compared to the case where road facilities are constructed, the scale of the entire road facility is smaller, which not only reduces construction costs but also immeasurably improves the stability and safety of the facilities. The ability to reduce the facility scale in this way expands the range of ground slopes on which roads can be constructed, making it easier to construct roads in mountainous areas. This applies not only to roads but also to all facilities built on steeply sloping ground.

That is, according to the method of the present invention, it is possible to easily construct an earth retaining wall on sloping ground without performing large-scale excavation, and moreover, the earth retaining wall can be constructed by supporting the load of the earth retaining wall body in a direction perpendicular to the sloping ground. It is possible to prevent the wall body from sliding sideways along the sloped ground and actively prevent the earth retaining wall body from falling over, making it possible to construct a safe and stable earth retaining wall in a short period of time and economically. In addition, it can also contribute to the conservation of the natural environment. Therefore, it can be said that the method for constructing a retaining wall according to the present invention is an invention having extremely large effects.

[Brief explanation of the drawing]

Figures 1 to 3 are longitudinal cross-sectional views showing each example of the conventional method on the same scale, and Figure 1 shows an example in which a road is widened by embankment on sloping ground.
Figure 2 shows an example in which the amount of embankment in Figure 1 is reduced and a cut is provided on the mountain side, and Figure 3 shows an example in which the embankment is protected by a retaining wall without providing an embankment slope compared to Figure 1. This figure shows an example. 4 to 6 are for explaining each embodiment of the longitudinal cross-sectional shape of the main body of the method of the present invention, FIG. 4 is a combination of a vertical surface part and a circular arc surface part, and FIG. 5 is a combination of a vertical surface part and a circular arc surface part. A combination of a face part and a lower face part, No. 6
The figure is a longitudinal sectional view showing a combination of a vertical surface portion and a paraboloid surface portion. Figures 7 to 16 show an example of constructing an earth retaining wall by the method of the present invention.
The figure is a vertical cross-sectional view of the overall structure, Figure 8 is a plan view cut along the A-A cutting line in Figure 7 and the back embankment has been removed, and Figure 9 is a B-B in Figure 7. A front view along the arrow line, FIG. 10 is a perspective view of the upper panel,
Figure 11 is a perspective view of the middle panel, Figure 12 is a plan view of the base panel, Figure 13 is an enlarged vertical cross-sectional view of the main part explaining the specific procedure for constructing an earth retaining wall, and Figure 14 is the base panel and lower panel. FIG. 15 is a longitudinal cross-sectional view showing the main parts of the connection between the upper panel, the middle panel, and the lower panel. Further, FIG. 16 is a longitudinal sectional view showing an example of road widening by the method of the present invention.
It is illustrated to the same scale as FIGS. 2 and 3. 1...Main body of earth retaining wall, 11...Upper cable,
12...Lower cable, 13...Upper panel, 1
4...Middle panel, 15...Lower panel, 16...
...Base panel, 17...Abutment, 32...PC steel bar.

Claims (1)

[Scope of Claims] 1. Supporting ground that supports the earth retaining wall body is formed at the site where the earth retaining wall body is constructed for the sloped ground, and a retaining wall is provided at the back part of the earth retaining wall body.
A retaining portion consisting of support piles, lock anchors, etc. is formed, and the retaining wall body is configured on the supporting ground in a reverse slope so that the load of the retaining wall body is applied in a vertical direction to the supporting ground. An earth retaining wall for sloping ground, characterized in that the earth retaining wall is constructed by connecting the earth retaining wall body to the retaining part via a retaining member made of cables or the like, and embanking the earth retaining wall body to a required height on the back side of the earth retaining wall body. How to build a wall. 2 Claim 1, characterized in that the retaining wall body is constructed of cast-in-place reinforced concrete.
Method for constructing earth retaining walls on sloping ground as described in section. 3. A method for constructing an earth retaining wall on sloping ground according to claim 1, characterized in that the earth retaining wall main body is constructed by using precast concrete members and integrally made of prestressed steel or the like. 4. A method for constructing an earth retaining wall on sloped ground according to claim 1, characterized in that the earth retaining wall main body is constructed by assembling and integrating steel shapes, steel plates, etc. 5 Claim 1 characterized in that the earth retaining wall main body and the retaining part are connected via a cable.
Method for constructing earth retaining walls on sloping ground as described in section.