JP-7856478-B2 - Method for constructing earth retaining structures using steel shell elements

Inventors

• 浅野 均
• 田中 孝
• 田中 宏典

Assignees

• 戸田建設株式会社

Dates

Publication Date

20260511

Application Date

20220428

Claims (4)

1. A method for constructing an earth retaining structure using steel shell elements, wherein multiple rows of steel shell elements are arranged in parallel, with multiple steel shell elements connected in the direction of penetration , by sequentially penetrating the ground downwards while connecting them to already penetrated steel shell elements, Earth anchoring work involves installing earth anchors near the area where the earth retaining structure is planned to be constructed, The steel shell elements are provided with joints to sequentially connect the steel shell elements that have already been penetrated, and by pre-drilling the planned penetration area of the joints, the in-situ ground in the planned penetration area is loosened and relaxed without completely removing the in-situ soil, and The system is equipped with a thruster that excavates the tip when the steel shell element is penetrated, and a push jack that secures reaction force with the earth anchor is installed on the launching side, and the steel shell element is sequentially driven into the thruster at the tip in a standard element construction process, A push jack with a reaction force secured by the aforementioned earth anchor is installed on the launching side, and the subsequent element installation is carried out by sequentially attaching the steel shell elements to the thrusting machine at the tip, connecting them with the already-attached steel shell elements as they penetrate, An element-inter-element soil removal work for removing soil between the aforementioned steel shell elements, A stress member installation method is used to install stress members within the steel shell element, at a location that bears the stress of the earth retaining structure, and along one side and the other side of the earth retaining structure, extending a portion or the entire length of the penetration direction of the steel shell element. A concrete filling process for filling the inside of the steel shell element and the spaces between the steel shell elements with concrete, A method for constructing an earth retaining structure using a steel shell element, characterized by including the element.
2. A method for constructing an earth retaining structure using steel shell elements according to claim 1, wherein in adjacent rows of steel shell elements, the joints between adjacent steel shell elements in the penetration direction are provided at different positions with respect to the penetration direction.
3. A method for constructing an earth retaining structure using steel shell elements according to claim 1 , wherein, after the earth removal work between the elements, a joint grouting work is provided in which grout material is filled into the joint.
4. The method for constructing an earth retaining structure using a steel shell element according to claim 1 , wherein, after the completion of excavation, the thrusting machine recovers as much of the material inside other than the skin plate as possible , leaving at least the skin plate at the lower end of the earth retaining structure.

Description

This invention relates to a retaining wall structure and a method for constructing the same, using steel shell elements formed by sequentially penetrating steel shell elements downward into the ground while connecting them with pre-penetrated steel shell elements. Conventionally, the diaphragm wall method has been known as one of the earth retention (shoring) methods for constructing open-cut tunnels, shafts, and the underground sections of buildings. In large-scale open-cut excavations, the diaphragm wall method involves excavating in a trench shape (trench excavation) while stabilizing the trench wall using a stabilizing fluid such as bentonite. After excavation is complete, core materials such as reinforcing cages or H-beams are installed in the trench, and concrete is poured while replacing the stabilizing fluid to construct a continuous reinforced concrete wall (RC diaphragm wall) underground (for example, see Patent Documents 1 and 2 below). Japanese Patent Publication No. 2001-303553Japanese Patent Publication No. 2003-155742Japanese Patent Publication No. 2015-71904 This is a plan view of the earth retaining structure 1 according to the present invention.That frontal declaration.This is a cross-sectional view taken during tunneling construction.This is a perspective view showing the steel shell element 2.This is a cross-sectional view of joint J.This is a cross-sectional view of the concave joint 23.This is a plan view showing the earth anchor installation.This is a cross-sectional view showing the earth anchoring work (viewed along the line VIII-VIII in Figure 7).This is a plan view showing the pre-drilling work at the joint.This is a cross-sectional view showing the pre-drilling work at the joint (viewed along the line X-X in Figure 9).This is a plan view showing the installation of the standard element.This is a cross-sectional view showing the construction of the standard element (viewed along the line XII-XII in Figure 11).This is a plan view showing the construction of the subsequent elements.This is a cross-sectional view showing the construction of the subsequent element (viewed along the line XIV-XIV in Figure 13).This is a plan view showing the removal of sediment between elements.This is a cross-sectional view showing the removal of sediment between elements (viewed along the line XVI-XVI in Figure 15).This is a plan view showing the grout filling process inside the joint.This is an enlarged cross-sectional view of joint J.This is a plan view showing the concrete filling process.This is a cross-sectional view showing the concrete filling process (viewed along the line XX-XX in Figure 19). The embodiments of the present invention will be described in detail below with reference to the drawings. The earth retaining structure 1 according to the present invention, as shown in Figure 1, is an earth retaining wall constructed in close proximity to important underground structures such as subway lines and stations. It is constructed by interconnecting multiple steel shell elements 2 from the ground surface to a predetermined depth in the ground, in order to minimize ground displacement. As shown in Figures 1 to 3, the earth retaining structure 1 is formed by sequentially penetrating steel shell elements 2 downwards into the ground, connecting them with pre-penetrated steel shell elements 2, thereby creating a structure in which multiple rows of steel shell elements 3 are arranged in parallel . In other words, a wall is formed by connecting multiple steel shell elements 2 downwards into the ground from the ground surface to form rows of steel shell elements 3 extending to a predetermined depth, and arranging multiple rows of these steel shell element rows 3 horizontally while connecting them to each other. To penetrate the steel shell element 2 into the ground, as shown in Figure 3, a push jack 5, secured by a reaction force from an earth anchor 4 driven deep into the ground near the planned construction area of the earth retaining structure 1, is installed on the starting side, and the steel shell element 2 is driven behind the thruster 6 at the tip. In this way, the excavation wall is covered by the following steel shell element 2 immediately after excavation by the thruster 6, so the excavation wall is not left in an excavated state, ground deformation is suppressed, and the collapse of the trench wall is prevented. Furthermore, since concrete is filled inside the penetrated steel shell element 2 and between adjacent steel shell elements 2, 2, and integrated, a highly rigid and high-quality earth-retaining structure is obtained. As the steel shell element 2, the one described in Patent Document 3 (Japanese Patent Publication No. 2015-71904) can be suitably used. Specifically, as shown in Figure 4, the steel shell element 2 is a rectangular cross-section element composed of an upper plate 20, a lower plate 21, and side plates 22, 22. In this steel shell element 2, the upper plate 20 or the lowe