JPS61191724A - Drawing work for closed steel sheet pile - Google Patents

Abstract

PURPOSE:To easily drawn out steel sheet piles by a method in which a steel sheet pile is cut off in the longitudinal direction at the center of its widthwise direction and a coupler and a sealing member are provided to the cut parts in such a way as to reduce the horizontal pulling force of the sheet pile. CONSTITUTION:A steel sheet pile 6a is cut off in the longitudinal direction at the center of its widthwise direction, and a U-shaped coupler 6c whose outside is opened is fixed to the end face of one cut part 6b. The other cut part 6d is inserted into the coupler 6c. Two steel bars 15 covered with a sealant 14 are airtightly inserted between the coupler 6c and the cut part 6d to form a steel sheet pile 6a of almost the same shape as the sheet pile 6. The piles 6a are connected and inserted into a or several places of the sheet pile 6 in such a way as to reduce the horizontal pulling force of the pile 6. In drawing out the piles, the bars 15 are pulled out in advance for loosening between the coupler 6c and the cut part 6d, and then the piles 6a are drawn out.

Description

[Detailed description of the invention] There are many types of earth retaining methods for excavation construction, but in the past, the steel sheet pile method and the H-copper loss sheet pile method were used.
PIF construction method and continuous underground wall construction method have been widely used as mountain retaining wall construction methods since before 1999, and continuous underground walls with high rigidity are being frequently constructed in relatively deep excavations.

Recently, mud water solidification method and three-speed organ illumination method have been adopted for cut-and-cover construction in large urban areas to minimize noise, vibration, groundwater drop, and ground subsidence that interfere with the lives of residents around the construction site. .

However, even in these earth retaining methods, steel sheet piles and H steel piles are used as stressed steel materials, and when the stressed materials exceed 20 m, they are buried even though they are no longer needed after the construction is completed. Currently, this is because no method has been found to economically pull out the stressed materials, but it is now required to pull them out and remove them after construction is completed.

This is done not only to save resources and reduce costs, but also to excavate underground areas of public and private land, so if it is long, excavate it with earth retaining material on both sides from the ground surface to about 6 meters underground. This requires the double and triple effort of cutting the stressed material and backfilling it again.

Therefore, currently, steel sheet piles are mainly used as stress materials in the mud water solidification method, and H steel piles are mainly used as stress materials in the double organ illumination method. limited to.

The present invention is an invention of a method for pulling out long objects of 20 m or more, which has not been attempted yet, and a method for pulling out objects under sandy and gravel ground conditions.

To explain this example, double-sided tape (2) is pasted on one side of a wide polyethylene film (1) in the longitudinal direction and at or near the outer edge to form a covering material (5). Is it possible to form a covering material (5) by pasting asphalt tape (4) on one side of a wide asphalt paper (3) at the middle and outer edges in the longitudinal direction? Form and prepare.

In the width direction of the covering material (5), from the outer end extension line part (8) of the engaging part (7) of the steel sheet pile (6) to the outer end front corner part (9) of the engaging part (7) The covering material is adhered to the entire surface except for the interval (2) up to the end, and the entire length in the longitudinal direction except for the lower end part 100 to 2001111. (5) and the steel sheet pile (6), apply auxiliary tape On such as gummed tape or asphalt tape from the outside so that it spans both the steel sheet pile (6) and the covering material (5).
Prevent muddy water from entering the gap 1■.

Furthermore, an antifriction agent such as grease is applied to the bare surface part αυ of the steel sheet pile (6) to which the covering material (5) and the auxiliary tape frame are not attached. As an anti-friction agent, Sanhitstorefgo,
Manor, puck release D.

Clean F
D. An oil layer such as high slide wax, a coating system such as Pirares, vinyl coat, IPA wax, etc., waste oil, aluminum powder, etc. can be used.

As mentioned above, the preparation of the steel sheet pile (6) for erection is completed,
In parallel with this, excavation holes U2 are excavated at regular intervals by an excavator in a predetermined location in the ground, the remaining soil is treated, mud water solidification liquid is filled in the excavation holes (ta), and the steel sheet piles (6) are lifted by a crane. Erecting, several steel sheet piles (6) are connected to each other at their engaging parts (7
), and after the predetermined number of erections are completed, the vertical accuracy and alignment of the steel sheet pile (6) are checked by f4.
12 excavated holes were drilled, filled with muddy water solidification wall, and steel sheet piles (
6) Z construction forms a continuous earth retaining wall u3.

The steel sheet pile (6) is pulled out using a mule crane.

Steel sheet pile (6) has 4 sheathing materials (5)! L is overturned and can be easily removed with force.

Next, the overall pulling method is as described above, but steel sheet piles (6
), a large pulling force is required when pulling out the steel sheet pile (6) (especially the first one) due to the horizontal tension (closability) of the steel sheet pile (6) during the four steps. This causes problems such as not being able to completely pull it out and remove it.

In order to solve this problem, in addition to the above-mentioned overall drawing method, the following configuration is added. ・One steel sheet pile (6a) is placed in the longitudinal joint member (6c) at the center of the width direction, and the cutting member (6c) on the other side is inserted. 6d) 'a' Insert two steel rods (19) coated with sealing material I between the joint member (6c) and cutting member (6d) and insert the steel sheet pile (
6) forms a steel sheet pile (6a) with the same shape as y, and the steel sheet pile (6a) is
6a) are inserted into one or several locations of the steel sheet piles (6) that are continuously engaged and connected to reduce the horizontal tensile force to form the earth retaining wall u3, or the steel sheet piles (6) ) of the steel sheet pile (6) on the inner side of the inclined part (6) of the steel sheet pile (6) overlaps the inclined part (6) of the inclined part (6) of the steel sheet pile (6) without engaging and connecting with force. -' location or number of steel sheet piles (6) to which an expandable sealing material (LE is pasted to maintain airtightness, such an overlapping part U?) is connected between the steel sheet pile (6) and the inclined part (6). It is formed in the soil to reduce the horizontal tensile force.

In the case of steel sheet piles (6a), first pull out the steel bar housing 9 to give slack between the joint member (6C) and the cutting member (6d), and then remove the cutting member (6b) or cutting member of the steel sheet pile (6a). (
It can be easily pulled out by pulling out 6d).

When the inclined parts (d) and the inclined parts (d) are overlapped, the steel sheet pile (6) having the inclined parts (d) can be easily pulled out by first pulling out the steel sheet pile (6). It can be pulled out easily and quietly with a tensile force of tons.

Furthermore, due to regulations such as the Road Traffic Act, steel sheet piles (6) that are as long as 25 meters cannot be transported, so they are welded on site to form a long object. This is done by butt welding (21) or by overlapping and welding plates on one or both sides of the location where the steel sheet piles (6) are butted together.

Further, the plate u8 may be a rectangular member, but if the plate u8 is made into a vertically long diamond-shaped plate 4 in consideration of the pull-out resistance, the pull-out resistance can be further reduced.

When welding joints in such a busy period, there is no problem in the case of butt welding D, but because the plate (if welded by overlapping II) UL19 is thick, it is difficult to attach the covering material (5). Steel sheet piles (
6) and the step part of the plate (11) is filled with clay, etc. to form a triangular butt@, and from this outer surface, cover material (5)
Damage can be prevented by pasting it.

Even when it is pulled out, the two batts reduce the resistance and can be pulled out smoothly.

Next, we will discuss the pull-out experiment.

Pulling out experiment 1) Comparative experiment of anti-friction agents and coating anti-friction agents Among the classified anti-friction agents, three types of anti-friction agents were selected based on their particularly low pull-out resistance and economic efficiency.
We selected two types of coating materials that completely eliminate adhesion to steel materials and conducted experiments. The anti-friction agents and coating materials used in the experiment are as follows.

a) Adding anti-friction agent - High Slide Wax - Waste oil + aluminum powder b) Covering material - Polyethylene film (0.3M) - Asphalt paper 2) Test sample The formulation was the same as in the comparison experiment of anti-friction agent. The same is true, and the compressive strength is 3.83 at 7 days of age, 9/CI! :Met.

3) Experimental results of maximum resistance force and frictional resistance force during sliding are shown in Table-1 and Figure-1.
4 to Figure 19.

As described above, it was found that asphalt paper and polyethylene film have very small maximum resistance and frictional resistance, and can be pulled out with a small tensile force.

A covering material such as polyethylene film or asphalt paper is applied to the entire front and back surfaces of the sheet piles, and the rest of the sheet piles that are not pasted are coated with grease. The purpose described below can be achieved after constructing an earth retaining wall around the entire circumference within the excavation hole.

[Brief explanation of drawings]

Figures 1 and 2 are perspective views of the covering material, Figure 3 is a plan view of the steel sheet pile, Figure 4 is a front view of the same, Figure 5 is a plan view of the ground in the excavated area, and Figure 6 is the overall view. A plan view of the ground that formed the retaining wall,
Figures 7 and 8 are plan views of the deformed joints of steel sheet piles;
The figure is a front view of a long steel sheet pile, Figures 10 and 11 are front views of the joint, Figure 12 is a sectional view of the joint, Figure 13 is a cross-sectional view of the joint, and Figure 14. 19 to 19 show experimental results of the pulling resistance force and the amount of pulling displacement.

Claims (3)

[Claims] (1) In the muddy water solidification method using steel sheet piles, the construction of a structure to reduce the horizontal tension on the steel sheet piles at one or more places in the vertical shaft closed with steel sheet piles is delayed after the construction of the underground structure is completed. A method for pulling out closed steel sheet piles, which is characterized by pulling out steel sheet piles with a structure that reduces tension in the horizontal direction. (2) Drawing of a closed steel sheet pile, characterized in that the structure for reducing horizontal tension according to claim 1 is provided with an engaging portion in the longitudinal direction at the center of the width direction of the steel sheet pile. Construction method. (3) The structure for reducing horizontal tension as set forth in claim 1 is formed by superimposing the inclined parts of the steel sheet piles on both sides inside the inclined part of the steel sheet piles via an expandable sealing material. A method for drawing closed steel sheet piles.