JPH05132939A - Installation method of underwater strut - Google Patents

Abstract

PURPOSE:To facilitate underwater construction work by manufacturing temporary bearing beams capable of piling struts in a plurality of stages, suspending and installing them after land slide protection walls are constructed, and suspending the struts with the progress of excavation to indicate the landslide protection walls. CONSTITUTION:On the ground, temporary bearing beams 1 and 2 having two stages of up and down providing construction jacks 21 to the sides are manufactured. The temporary bearing beams 1 and 2 is so constructed that struts 4 can be piled up in a plurality of stages. After landslide-protection walls are constructed on the ground, suspension lanes 6 are installed, the temporary bearing beams 1 and 2 are suspended with cables 3, and the landslide protection walls are held by the construction jacks 21. After that, the struts 4,... are suspended in accordance with the progress of excavation of the landslide protection walls 5, the landslide protection walls 5 are temporarily held and, at the same time, the struts are provided between the landslide protection walls 5 from the top to the bottom. According to the constitution, underwater construction can be mechanically made, and underwater work by divers and others can be omitted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of installing an underwater girder.

[0002]

2. Description of the Related Art In recent years, there is an increasing need for deep underground use in cities, and therefore, the development of a deep depth excavation method is urgent. At present, as one of effective methods for deep-depth drilling, there is a method of reducing the earth pressure and water pressure acting on the retaining wall by performing the drilling underwater. In this underwater excavation, as shown in FIG. 10, conventionally, a diver enters the water and installs a crossbeam b between the mountain retaining walls a in water by the same method as installing a crossbeam in a general shaft. ..

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
There are the following problems. <B> Since heavy objects are handled underwater, the level of danger is higher than that of general cutting beam installation methods. <B> Since it is an underwater operation, it takes more time than the general method of installing a crossbeam. <C> Since people work underwater, there is a limit to the depth of cutting beams that can be installed, making it difficult to meet the needs for deep drilling.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an installation of an underwater girder capable of quickly and easily performing an installation work of an underwater girder. The purpose is to provide a method. That is, the present invention, when excavating the ground between the mountain retaining walls underwater, in the method of installing the beams to be installed between the mountain retaining walls, stacking the beams in a plurality of stages and connecting them so that they can be suspended by a cable. The sill beams are suspended according to the progress of excavation in between, and the mountain retaining walls are temporarily supported while being rearranged by the lower and upper tier beams, and the sill beams are placed between the mountain retaining walls in descending order from the upper tier beam. It is a method of installing an underwater girder, which is characterized by being installed in.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. <B> Temporary Support Beams (FIGS. 1 and 7) Temporary support beams are provided at the lowermost stage and the upper stage of the beam group, as shown in FIG. 1, to form upper and lower temporary support beams 1 and 2. .. Although FIG. 7 shows the upper temporary support beam 1, the lower temporary support beam 2 has the same structure. These temporary support beams have a hollow structure,
It is constructed so that its own weight can be kept small by buoyancy in water. In addition, the side walls are provided with erection jacks 11 and 21, and by projecting these, the surrounding mountain retaining wall can be pressed and temporarily supported. Then, the upper and lower temporary support beams 1 and 2 are connected to each other in the vertical direction by the suspension cable 3.

<B> Cut Beam (FIGS. 1, 8 and 9) The cut beam 4 is a portion stacked on the upper part of the upper temporary support beam 1 as shown in FIG. 1, and has a hollow structure similar to the temporary support beam. And reduce the underwater weight. 8 and 9 show the structure of the cross beam 4. The cutting beam 4 has a form tube 41 on the outer peripheral edge of the bottom surface.
The mold tube 41 is filled with an injection material through the mold tube injection pipe 42 so that the mold tube 41 can be expanded. In addition, a filling concrete injection port 44 communicating with the filling concrete injection pipe 43 is appropriately provided on the side surface of the girder 4. Further, a cable through hole 45 for penetrating the hanging cable 3 is appropriately opened.

<C> Arrangement of Temporary Support Beam and Crane (FIGS. 2 and 3) First, as shown in FIG. 2, a mountain retaining wall 5 is constructed on the ground by a known method. Next, as shown in FIG. 3, the suspension crane 6 is installed, and the upper and lower temporary support beams 1, which are produced on land,
2 is suspended by the suspension cable 3.

<D> Arrangement of Girder (FIGS. 4 and 5) Next, as shown in FIG. 4, after underwater excavation to some extent, the lower stage temporary support beam 2 is hung and the erection jack 21 is projected to make a mountain clasp. Temporarily support the wall 5. Then, as shown in FIG. 5, a required number of cut beams 4 are stacked and arranged on the upper part of the upper temporary support beam 1, and are connected by the hanging cable 3.

<E> Installation of the girder between the mountain retaining walls (Fig. 1,
6, 9) Following the progress of the underwater excavation, the group of beams is suspended as shown in FIG. 6, and the mountain retaining wall 5 is temporarily supported while the lower temporary support beam 2 and the upper temporary support beam 1 are rearranged, Girder 4 on the upper stage
It is installed between the mountain retaining walls 5 in order from the bottom. When installing the girder 4, as shown in FIG. 9, the formwork tube 41 is inflated and brought into close contact with the mountain retaining wall 5, and the space-filled concrete 4 is inserted above the space-filled concrete injection pipe 43.
6 is placed to achieve integration. By repeating the above work, the crossbeam 4 is installed to a predetermined depth as shown in FIG. 1, and the work is completed.

[0010]

Since the present invention is as described above, the following effects can be obtained. <B> Since the beams can be produced on land and can be erected mechanically underwater, there is no need for underwater work by divers and safe construction is possible.

<B> Since the entire construction is mechanized by the underwater excavation and the mechanical installation of the cross beam, the construction efficiency is improved.

<C> Since excavation and erection of beams can be performed in a fixed cycle, there is no need to change the work procedure and the process can be shortened.

[Brief description of drawings]

[Fig. 1] An explanatory diagram of the completed installation of the cross beam

FIG. 2 is an explanatory view of a construction process of a mountain retaining wall.

FIG. 3 is an explanatory diagram of a process of arranging a temporary support beam and a crane.

FIG. 4 is an explanatory diagram of a cutting beam arrangement process.

FIG. 5 is an explanatory diagram of a cutting beam installation process.

FIG. 6 is an explanatory diagram of a cutting beam installation process.

FIG. 7 is an explanatory diagram of a temporary support beam.

FIG. 8 is an explanatory view of a cross beam

FIG. 9 is an explanatory view of a cross beam

FIG. 10 is an explanatory diagram of a conventional technique.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kennosuke Watanabe 1-25-1 Nishishinjuku, Shinjuku-ku, Tokyo Taisei Corporation

Claims (1)

[Claims] 1. When excavating the ground between the mountain retaining walls underwater,
In the method of installing the beams to be installed between the retaining walls, stacking the beams in multiple stages and connecting them so that they can be suspended with a cable, and suspending the beams in accordance with the progress of excavation between the retaining walls, An underwater truss installation method characterized by temporarily supporting the mountain retaining wall while reassembling with the upper beam, and installing the lower beam between the mountain retaining walls in order from the upper beam.