KR200331377Y1 - Soil Cement Wall with Removable H-Pile - Google Patents

Abstract

The present invention recovers Hp pile when dismantling temporary facilities due to attachment of Soil Cement and H-Pile steel in Soil Cement Wall (SCW) By solving the problem that must be buried in the ground as it does not, it is to recycle the steel materials to reduce construction costs and remove underground obstacles. The present invention prevents the attachment of H-PILE and Soil Cement by wrapping H-PILE purchased during Soil Cement Wall (SCW) construction with Geotextile and embedding in Soil Cement. After the excavation is completed, H-PILE is to be collected and retrieved using a vibro hammer.

Description

H Pile Cement Wall with Removable H-Pile

Soil cement wall (S.C.W) as shown in Figure 1 is a temporary temporary barrier wall that is very frequently applied in the construction of a large depth of excavation, such as subway, underground storage facilities, high-rise building construction. Construction of a soil cement wall (S.C.W) made of steel such as the soil cement (1) and the H pile (2), and excavation while supporting with a strut (5) or anchor (6) as the excavation proceeds. The construction of the small cement wall (SCW) is carried out by cutting the auger on the base and stirring the hardened materials of cement milk and bentonite with the base soil, as shown in FIG. Soil cement (1) consists of a continuous wall and embeds the H pile (2) in the soil cement (1) circular bulb to suppress the ground breakage and displacement caused by vertical excavation, to prevent groundwater outflow, and to reduce the groundwater level in the surrounding area do.

design

The basic concept of design of S.C.W is to transfer earth pressure from excavation to steel materials such as H pile (2), which is loaded by Soil cement (1). At the time of design, the soil cement (1) and the H pile (2) are separated and examined for stability.

In the case of the small cement (1), the design strength of the small cement (1) is determined and the compounding ratio is determined so that compressive fracture and shear failure do not occur with respect to the working earth pressure. Compression failure of the soil cement (1) is examined assuming the arching shape, and shear failure is considered assuming the fracture section of the soil cement (1) corresponding to the width of the steel (Structure Foundation Design Criteria (Ministry of Construction and Transportation) ), See pages 347-352).

During the axial load due to the load transmitted to the H pile 2, the bending moment and the shear force are applied in the same manner as the design of temporary walls such as a solid pile. The relationship between the soil cement (1) and the H pile (2) can be said to be the same as the relationship between the earth plate and the thumb pile in the thumb pile drilling rig. That is, the load acting on the small cement 1 is transmitted to the H pile 2 in the horizontal direction, and the H pile 2 is designed to independently ensure its stability. Therefore, the adhesion force and frictional force of the soil cement 1 and the H pile 2 are independent of the stability of the temporary installation and are not a problem even if the adhesion force or frictional force is lost or reduced.

City ball

Construction of small cement wall (SCW) is cut by overlapping with 3-axis auger (1-axis auger may be used depending on the ground condition), and cement milk injection material pressure is 3 ~ 5kg through hollow loader of auger / cm2 is injected and mixed with the soil of the ground with stirring blades attached around the auger loader to make the wall of soil cement (1). After inserting steel materials such as H-pile 2 as stress reinforcement materials in the soil cement 1 at regular intervals based on the design, the work is carried out after a certain curing period. Even when the trench and backfill are completed, the H pile 2 embedded in the soil cement 1 cannot be pulled out by attachment and is left in the ground as it is.

Basic principles

The content of the design is very clear and simple. As shown in Figs. 3 and 4, instead of the conventional soil cement wall composed of the soil cement (1) and the H pile (2), the soil fiber (1) and geotextiles of single or double depending on the site conditions ( It is a small cement wall which consists of H pile 2 covered with 3). By enclosing the outside of the H pile 2 with the geosynthetic fiber 3, the attachment of the external soil cement 1 and the H pile 2 is prevented. After curing, the H pile 2 comes into contact with the coated geotextile 3 so that unlike the conventional SCW wall, there is no attachment of the H pile 2 and the SOIL cement 1, thereby vibro hammer. It is possible to recover the draw using such.

Design background

a. Soil cement wall (S.C.W) is a temporary structural structure, but the H pile (2) is still in the ground, the loss of steel is enormous, and has a problem of leaving the ground obstacle.

b. In the design concept, the attachment of the small cement (1) and the H pile (2) does not affect the stability of the temporary facility.

c. Recently, with the development of geotextile (3) technology, materials with high water tightness and high strength are being developed one after another.

Considerations

The following points were considered in the design.

a. Cement milk penetrates between the geosynthetic fibers 3 and may cause a problem of adhesion. It can be prevented by adopting the civil fiber (3) excellent in watertightness, and can be solved by covering the double civil fiber (3) or by placing a vinyl sheet (VINYL SHEET) inside the civil fiber (3) if necessary.

b. When the geosynthetic fiber 3 and the H pile 2 are simultaneously entered, a problem may occur in which the geotextile 3 is broken. This is expected to vary depending on the ground conditions, which can be solved by identifying sufficient ground conditions in advance and adopting geotextiles 3 of appropriate strength. If there is a risk of damage to the tip portion, adopting a high-strength geotextile (3) and at the same time as attached to the steel reinforcement cap (4) at the tip as shown in Figure 5 can be solved the problem of breakage.

Figure 1 is a representative order earthquake construction section to which the Soil Cement Wall (S.C.W) method is applied

FIG. 2 is a plan view of a small cement wall (S.C.W) that has been conventionally applied. The spacing, the strength and composition of the small cement (1) and the size of the H pile (2) are determined by design.

Figure 3 is a plan view of the soil cement wall (S.C.W) proposed in the present invention to cover the H pile (2) with a single or double geosynthetic fiber (3) embedded in the soil cement (1)

4 is a sectional view of the small cement wall (S.C.W) proposed in the present invention

FIG. 5 illustrates that when the H pile (2) is embedded in the soil cement (1), when the civil fiber (3) located at the distal end may be damaged, the steel reinforcing cap (4) is covered with the steel fiber (3).

<Description of the symbols for the main parts of the drawings>

1. Soil Cement 2. H-Pile

3. Geotextile 4. Steel reinforcement cap

5. Strut 6.Anchor

7. King Post

The content of the invention is described below.

a. Soil cement wall consisting of a stirred soil cement (1) and the H pile (2) wrapped in a single or double geosynthetic fiber (see Figs. 3 and 4).

b. Steel reinforcing cap (4) installed on the tip to prevent damage to the geotextile (3) according to the ground conditions (see Fig. 5).

The basic purpose of the present invention is the recovery of the H pile (2) steel and additionally several effects can be expected. The main effects are as follows.

a. Save resources with steel recycling

b. Cost reduction

c. Underground obstacle removal

Claims (2)

Soil Cement Wall with embedded H-pile (2) coated with single or double geotextile (3) inside the stirred soil cement (1) delete