JPH042727B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of constructing double wall structures. The present invention is particularly valuable when applied to double wall structures used for mountain and flood control. Our country is often hit by torrential rains caused by typhoons and has steep mountainous areas.
Water flowing down steep slopes not only erodes and devastates slopes and riverbeds, but also turns into mudflows that attack forests, rivers, civil engineering structures, cultivated land, and villages, causing great damage. In addition, damage caused by mudflows and landslides caused by rain or collapse of volcanic ash and debris deposited by volcanic eruptions is also significant. A particular object of the present invention is to provide a method for constructing a double wall structure, such as a double wall erosion control dam, to prevent such damage.

Conventionally, known methods for constructing such double wall structures include the Terre Alme construction method, which uses reinforced concrete or metal skin segments and strips, and the TUV construction method, which uses expanded metal skin segments and tie rods. However, since the Terre Alme construction method relies on the frictional force between the strip and the filling earth and sand, there are significant restrictions on the filling earth and sand material and on the distance between walls based on the strip length. In other words, if the soil generated on site during excavation cannot be used for filling, it is necessary to dispose of it and use separately prepared soil, or to stabilize the generated soil and use it. Also, it is often necessary to perform large-scale excavation to ensure sufficient distance between walls. Expanded metal structures are very advantageous because they can be constructed quickly and only require a small amount of materials to prepare and transport; however, if the filling material flows out or settles after construction, the wall surface may become deformed. Therefore, it is necessary to carefully consider various conditions such as the selection of filling materials, compaction, and the use of anti-wicking materials when designing.

Therefore, the present inventor conducted repeated research and discovered a new method for constructing a double wall structure that is easier to design and construct and can construct a stronger double wall structure, and completed the present invention.

That is, the present invention provides (a) a plurality of steel sheet pile segments that can be connected to each other at the side ends, and (b) each segment, with horizontally adjacent segments being vertically shifted from each other. (c) Repeat the connection process in (b) above to form a double wall in which multiple rows of segments each lined up in the vertical direction are connected in the horizontal direction. (d) At any appropriate stage during the connection process of (b) and (c) above, both walls of the double wall are connected with a tie member, and earth and sand is filled between the two walls. , provides a method for constructing a steel sheet pile segment double wall structure.

The double partition wall construction method using steel sheet piles is known per se. However, this construction method involves driving a steel sheet pile, that is, a steel plate shaft, into the ground in the form of a double wall, and is merely one form of using steel sheet piles as a plate shaft. The present invention makes use of the characteristic of steel sheet piles, in which the butts on both side end faces of adjacent plate-like piles are interconnected, and the basic characteristics of the piles are segmented into blocks. Based on the unique idea of changing to a unit. This idea of segmenting a shaft to be driven into the ground and assembling it as a unit in multiple stages on the ground is completely new and not found in the prior art.

According to the present invention, by segmenting steel sheet piles, the weight of the members is reduced, and by assembling these lightweight segments from below in multiple stages, this method eliminates the need for conventional steel sheet pile double partition wall construction methods. Large, hot construction machines are no longer necessary,
It has become possible to construct the system in areas with poor road conditions. Segmentation does not reduce the tensile strength of the interconnecting joints on both sides, but rather increases their ability to deform as the filling material settles or the ground settles, thereby increasing the overall strength and strength of the structure. Produces more favorable results in terms of stability.

In the method of the present invention, the filling earth and sand is supported by the rigidity of the steel sheet pile segment wall itself and the tension applied to the tie members, so it is different from the Terre Arme method, which relies on the frictional force between the strip and the filling earth and sand. In contrast, there are fewer limitations on the filling material and fewer limitations on the distance between walls.

Although steel sheet pile segments are heavier per unit than expanded metal units, they have excellent wear resistance and impact resistance, and because they do not have mesh openings, they can be used as filling materials using soil materials and construction methods. Great freedom of choice.

Although the steel sheet pile segments may be made in advance to a desired length, it is more advantageous to cut commercially available steel sheet piles into appropriate lengths and use them at lower cost.
Among commercially available steel sheet piles, it is preferable to use U-shaped steel sheet piles, which have a large moment of inertia. The use of lining material becomes unnecessary. The shape and structure of the joint of the connecting portion is arbitrary and can be appropriately selected from known ones.

Each segment is connected such that horizontally adjacent segments are vertically shifted from each other. By repeating this process, a plurality of segment rows in which a plurality of segments are lined up in the vertical direction are connected in the horizontal direction. Connections between rows are made by shifting the longitudinal position of the segments between adjacent rows of segments. The distance to shift is 1/of the length.
It is preferable to set it to 2. In this case, in order to make the heights of the top and bottom tiers of the double wall the same, it is sufficient to separately prepare a segment with a length of 1/2.

The tie member can be appropriately selected from known joint materials. It is preferable that both wall surfaces be quickly and firmly connected, and the protrusion to the outside of the wall surface may be small. A deformed steel bar with threaded joints is used as the longitudinal member, and an eye bolt is used as the connecting member.
Universal joints, coupling couplers, washers, L-shaped plates, nuts, etc. can be used. The arrangement of tie members can be designed as appropriate depending on the purpose, but in general, sufficient strength can be obtained by positioning every other segment row with one tie member in the center of each segment. It is also advantageous in terms of construction efficiency.

When the segment length is one level, it is advantageous to fill the earth and sand in each level. Filling increases the independence of each tier, and also facilitates the subsequent construction of the upper tier and the filling of the upper tier. The height of one stage, that is, the segment length, can be appropriately determined by taking into account the ease of transporting and assembling the segments and the overall construction efficiency.

The segments used do not necessarily have to have the same size and shape as long as they can be connected to each other.
If preferred for design reasons, it is easy to use materials with different dimensions and shapes together. For example, segments with drainage openings can be placed at desired locations.

Hereinafter, the present invention will be described in more detail with reference to the embodiments illustrated in the accompanying drawings.

A commercially available U-shaped steel sheet pile with a width of 0.8 m is cut in the transverse direction to produce a plurality of two types of segments: segment A with a length of 1 m and segment B with a length of 0.5 m.

FIG. 1 shows a perspective view of one embodiment of a double wall structure constructed according to the method of the present invention. For construction, first connect segments A and B alternately in the horizontal direction to form segment rows (1 to 2N
+1) The first stage (1/2 to 2N+1/1) has two sides, and both sides are connected with a tie member. Next, fill with earth and sand up to the height of segment B in the even numbered rows (2n: n=1 to N). Next, on each surface, the lower half of another segment A is connected between the upper half of the first stage segment A in the odd numbered row (2n-1) to form the second stage segment A in the even numbered row (2n). The lower half of another segment A is connected between the upper half of the second stage segment A of the even numbered row (2n) to form the second stage segment A of the odd numbered row (2n-1), and a tie member is used between both sides. Connect and fill with earth and sand to the height of the even-numbered row (2n) second stage segment A. By repeating this process and using segment B as the odd-numbered row (2n-1) segment in the uppermost stage T, a double wall structure with uniform height as shown in FIG. 1 can be obtained.

FIGS. 2 and 3 are a plan view and a side view, respectively, of the double wall structure shown in FIG. 1, and the details of the tie members, which are shown simply in broken lines in FIG. 1, are clearly shown. In this example, the tie member consists of an eye bolt 11, a universal joint 12, a deformed steel bar with threaded joints, and a joint coupler 14, and connects segments 10 forming odd-numbered rows of segments recessed from both wall surfaces to the inside of the wall. It is arranged like this.

FIGS. 4 to 7 are plan views (only FIG. 6 is a side view) of modified examples of the connecting portion between the tie member and the segment. In the example shown in FIG. 4, a universal joint 21 is fitted into the segment 20 and fastened with a washer 22, and a threaded deformed steel bar 23 screwed to the universal joint 21 connects both wall surfaces. In the example shown in FIG. 5, an L-shaped plate 34 is fastened to the segment 30 with bolts and nuts, and a universal joint 31 and a threaded deformed steel bar 33 are joined to this L-shaped plate 34. FIG. 6 is a side view of FIG. 5. In the example shown in FIG. 7, the segment 40 has a threaded deformed steel bar 44.
are directly joined with a nut 45.

Examples of erosion control dams using double wall structures shown in Figures 1 to 3 are shown in Figures 8 (front view) and 9.
(a front view and a sectional view taken along the line X-X) and FIG. 10 (a top view).

Dam 50, constructed using segments of 0.8 m wide, 1 m long and 0.5 m long, has a maximum width of 93.6 m and a maximum height
It measures 14.3m and has a maximum depth of 49m. The double wall structure has its main dam 51 and vertical wall 5
It is used in 2. Main dam 51 and vertical wall 52
Water passages 53 and 54 are formed in each, and the top and water passage side walls are protected with concrete. The main dam 51 and the vertical wall 52 are connected by a water tap 55 and its side wall 56. 57 shows the foundation concrete work, 58 shows the field line, 59 shows the segments, and 60 shows the tie members.

Since the main dam 51 and the vertical wall 52 are composed of multi-stage segments, they can easily be divided into multiple sections and raised with height differences in order to facilitate water treatment during construction. It is.

Even if the filler material sinks after construction, there is little chance that it will cause the wall surface to deform. There is a great degree of freedom in selecting soil materials and construction methods for filling, and river bed excavation for foundation work can be kept to a minimum area directly below the wall surface.

Furthermore, the outer wall structure is as strong as a steel sheet pile wall, has excellent abrasion resistance and impact resistance, and there is no need to use anti-wicking materials on the wall surface.

Assembly work is simple as it only involves fitting the segments and connecting them with tie members on both walls, making it easy to match the basic shape of the dam to the topography of the foundation ground. Therefore, not only construction but also design work can be done easily.

As is clear from the above, the present invention provides a method for constructing a double wall structure in a very clever manner based on the unique idea of segmenting steel sheet piles and assembling them into units in multiple stages on the ground. This is an extremely useful product for industry.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing one embodiment of a steel sheet pile segment double wall structure constructed according to the method of the present invention, and FIGS. 2 and 3 are plan views of the structure shown in FIG. 1, respectively. and a side view. Figures 4 to 7 are plan views showing modified examples of the connecting parts shown in Figures 2 to 3 (Figure 6 is a side view only).
It is. 8 to 10 are a front view, a cross-sectional view taken along the line X--X, and a plan view, respectively, showing an example of an erosion control dam using the structure shown in FIGS. 1 to 3. 50... Sabo dam, 51... Main dam, 52...
Vertical wall, 53, 54...Water passage, 55...Water tapping, 57...Foundation concrete work, 58...Site board line, 59...Segment, 60...Tie member.

Claims (1)

[Claims] 1. (a) A plurality of steel sheet pile segments that can be connected to each other at the side ends are prepared, and (b) each segment is arranged such that horizontally adjacent segments are shifted from each other in the vertical direction. (c) Repeat the connection process in (b) above to connect multiple rows of segments in the horizontal direction. (d) At any appropriate stage during the connection process of (b) and (c) above, both walls of the double wall are connected with a tie member, and earth and sand is filled between the two walls. A method of constructing a steel sheet pile segment double wall structure. 2. The method according to item 1 above, in which commercially available steel sheet piles are cut transversely into appropriate lengths as the steel sheet pile segments. 3. The method according to item 1, wherein the segments are connected to each other at their side ends such that horizontally adjacent segments are shifted from each other by 1/2 of their length in the vertical direction. 4. The method described in the preceding paragraph 1, in which the segment length is one level, and the double wall is constructed by alternately repeating the connection of one level, the connection of that level with a tie member, and the filling of earth and sand inside that level. . 5. The method described in 1 above, which uses threaded deformed steel bars as tie members.