JPH04169620A - Method of supporting multifunctional floor by sheathing wall in inverter-hammering process - Google Patents

Abstract

PURPOSE:To increase the efficiency and stability of an inverted-hammering process, by causing an oil-pressure driven jack and a screw jack, which are disposed between operation floors vertically movably installed to construction studs and a waling member inside sheathing walls, to be alternately operated to support the sheathing walls. CONSTITUTION:After completion of a primary excavation, an operation floor 1 constructed as a finally or normally installed floor slab is made and vertically movably installed onto construction studs 2. Next, in order to install waling members 8 and jacks, a space interval of about 1.0m is provided between the operation floor 1 and sheathing or landslide protection walls 7 and, after cleaning of excavation surfaces of the sheathing wall 7, the waling members 8 are installed. Subsequently, in a state wherein the soil pressure applied to the sheathing wall 7 is supported by an oil pressure jack provided between the waling member 8 and the operation floor 1, a screw jack which has simultaneously been provided is extended to fix the operation floor 1 and then the oil pressure jack is removed. And normally installed beams and slabs are finally installed and then excavation is carried out under the operation floor 1. Then, the screw jacks are removed. These process steps are repeated thereafter.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for supporting a multifunctional floor to a retaining wall in a reverse construction method.

(Conventional technology) With the reverse drilling method, when the ground is excavated, underground PC
a. Construction of the floor slab and earth pressure acting on the retaining wall,
This is a method of constructing underground structures while supporting water pressure.

However, reverse hitting has the following drawbacks.

1) The next excavation work cannot proceed until the constructed PCa beam supports the soil and water pressure of the mountain retaining wall. As a result, excavation work will be temporarily suspended.

2) After excavation, build PCa beams and reduce the soil and water pressure of the mountain retaining wall.
It takes a considerable amount of time to support it. During this time, deformation of the retaining wall may progress.

3) - For boat fishing, the height of the lowest floor is large, so in order to excavate the lowest floor, it is necessary to construct a temporary strut in the middle.

The present applicant has proposed a construction method that eliminates the disadvantages of the above-mentioned reverse construction method, saves temporary construction, saves labor, shortens the construction period, and improves safety in Japanese Patent Application No. 1-237216. The work floor is freely mounted, lowered to a predetermined position and crimped to the mountain retaining wall so that it also serves as a strut of the mountain retaining wall, and the formwork for constructing the underground framework is assembled and supported on the work floor; At the same time as pouring the concrete for the framework, excavate the lower part of the working floor, wait for the cast concrete for the framework to harden, remove the formwork on the working floor, and use the same working floor as the construction site for the next underground framework. "This is a reverse construction method using a multi-functional work floor, which is characterized by lowering the work surface to a maximum height and then repeating the above steps."

(Problems to be Solved by the Invention) In the above construction method, the working floor supports earth pressure as a retaining sill member until the permanent beams and floor slabs are erected, and the working floor There is a need for a method of supporting a work floor to a mountain retaining wall that can effectively support the earth pressure by the work floor, and can also quickly and reliably support the earth pressure at the new lowered position of the work bed. ing.

(Means for Solving the Problems) The method of supporting a multifunctional floor to a retaining wall in the reverse construction method according to the present invention was proposed in response to such demands.
A working floor is attached to the structure pillar so that it can be raised and lowered freely, and the working floor is lowered to a predetermined position and crimped to the retaining wall so that it also serves as a strut for the retaining wall, and the underground frame section is installed on the working floor. At the same time, the lower part of the working floor is excavated and the working bed is lowered to the next underground structure construction position. In the reverse construction method, which repeats the above process, the working floor and the inner side of the retaining wall are A group of hydraulic jacks and a group of screw jacks are interposed between the restoring structure constructed at This method is characterized by suppressing the floor and rising, and then removing the hydraulic jack group and reusing it for supporting work on the mountain retaining wall of the working floor at the lower position.

[Function] According to the present invention, as described above, when the work floor is lifted down to a predetermined position along the main structure pillar, the jack installed between it and the lift installed on the inner side of the retaining wall is immediately lifted down to a predetermined position. Of the group, the hydraulic jack group is operated to quickly support the earth pressure of the mountain retaining wall.

In this state, the screw jack group is operated and extended to prevent the work floor from lifting up, securely fix the work floor in the lift-down position, perform the required work on the work floor, and perform the work. Excavation of the lower part of the floor can be carried out.

After the work floor is fixed by the screw jack group in this way, the hydraulic jack group is removed and used for the work of fixing the work floor on the lower floor.

(Example) The present invention will be described below with reference to the illustrated embodiments.

After the first excavation is completed, a highly rigid working floor 1 configured as a permanent floor slab is constructed and mounted on the structure pillar 2 so as to be movable up and down.

In the figure, reference numeral 3 indicates an insertion hole for a PC steel wire 4 for suspending the work floor provided on the work floor 1, and 5 and 6 indicate a pit for transporting earth and sand and a pit for bringing in PC members provided on the work floor 1, respectively.

A distance of about 1.0 m is provided between the work floor 1 and the retaining wall 7 in order to attach the lifting material and the jack group.

Next, after cleaning the excavated surface of the mountain retaining wall 7, it was erected.
erect.

Two screw jacks 9 and four hydraulic jacks 10 with a force application capacity of about 100 tons are interposed between the hoisting machine 8 and the work floor 1, and the hydraulic jacks 10 are used to create a retaining wall. Support the earth pressure applied to 7, and in this state screw jack 9
After the work floor 1 is extended and the work floor 1 and the work floor 8 are fixed, the hydraulic jack 10 is removed.

Note that the above-mentioned work is performed at opposite ends of the work floor 1.

After fixing the working floor 1, the permanent beams and slabs are erected, and the lower part of the working floor 1 is excavated.Then, the screw jack 9 is removed, and the above steps are repeated.

(Effects of the Invention) According to the present invention, in the reverse construction method as described above, a group of hydraulic jacks, a screwer, and a group of screws are installed between the work floor and the backing built on the inner surface of the retaining wall. As the earth pressure of the retaining wall can be supported immediately after excavation is completed using a group of hydraulic jacks, deformation of the retaining wall can be minimized, improving construction safety. At the same time, the screw jack can reliably fix the lifted-down work floor to the backrest installed on the inner surface of the retaining wall. Further, after the work floor is fixed with the same screw jack, the hydraulic jack can be removed and used for other purposes.

At this time, by using a permanent slab or pressure platen on the lowest floor as a working floor that also serves as a strut material, it becomes possible to provide high rigidity and reliable support for the pile.

Further, according to the present invention, all work is performed on the work floor, so safety and work efficiency can be improved.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of the method for supporting a multi-functional floor to a retaining wall in the reverse construction method according to the present invention, and FIGS. 2 and 3 are hydraulic jacks, respectively. Side view showing the installation part of the key and screw jack, No. 4
5 and 5 are a cross-sectional view and a plan view, respectively, showing the implementation status of the reverse pouring method. 1... Working floor, 2... Structural pillar, 7... Retaining wall, 8... Rearranging, 9... Screw jar, Ki, 10... Hydraulic jack. Agent: Patent attorney Shige Okamoto (1 person) Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] A working floor is attached to the structure pillar so that it can be raised and lowered freely, and the working floor is lowered to a predetermined position and crimped to the retaining wall so that it also serves as a strut for the retaining wall, and the underground frame section is installed on the working floor. At the same time, the lower part of the working floor is excavated and the working bed is lowered to the next underground structure construction position. In the reverse construction method, which repeats the above process, the working floor and the inner side of the retaining wall are A group of hydraulic jacks and a group of screw jacks are interposed between the work floor and the raised bed, and after the hydraulic jack group supports the earth pressure of the retaining wall, the screw jack group is operated to connect the work floor and the bed. A method for supporting a multi-functional floor to a retaining wall in a reverse hammering method, which is characterized by suppressing uplift, then removing a group of hydraulic jacks, and reusing the work floor for supporting the retaining wall at a lower position. .