JPH0470424A - Lift-down underground structure construction method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a lift-down underground framework construction method developed for constructing underground floors of buildings.

[Conventional technology]

Most buildings built in the city center have a basement of about 1 or 2 floors, but due to the recent rise in land prices, in order to secure as much floor space as possible within the limited building area, There is a strong demand for more effective use of underground areas.

For this reason, it is no longer possible to achieve sufficient underground utilization with only two floors underground, and recently, basements with about five floors are being constructed.

[Problem to be solved by the invention]

However, since underground construction is carried out below the ground surface, it not only inevitably takes a long time, but also costs more than ground floor construction, and it is also necessary to give due consideration to safety.

This invention was proposed in view of these circumstances.
The object of the present invention is to provide a lift-down underground structure construction method that makes it possible to solve the above three problems.

[Means to solve problems]

In order to achieve the above object, the lift-down underground framework construction method according to the present invention constructs an underground continuous wall around the outer periphery of the underground floor to be constructed, and then installs columns for the underground floor inside the underground continuous wall. Then, the floor slabs for each basement floor are constructed above ground, and the floor slabs are lifted down while excavating the area below the ground level surrounded by the underground continuous wall, and each floor The floor slab is installed at the location where the floor slab is installed, fixed to the underground continuous wall and columns.

In addition, a continuous underground wall is constructed around the outer periphery of the basement floor to be constructed, and then a framework covering all floors of the basement floor is constructed above ground, and then the ground level below the ground level surrounded by the continuous underground wall is constructed. The entire basement floor structure may be lifted down while the section is excavated underwater.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a lift-down frame construction method according to the present invention will be explained in order based on an embodiment illustrating the method.

■(Construction of an underground continuous wall) The underground continuous wall 1 is constructed around the outer periphery of the basement floor of the building to be constructed using cast-in-place reinforced concrete or PC concrete boards, etc., although it differs depending on the scale of the building etc.
(See Figures 1 and 2).

Further, the underground continuous wall 1 is constructed continuously from the ground level to the foundation of the lowest floor.

■(Column construction) Pillars 2 will be constructed at the predetermined location within the site surrounded by the underground continuous wall 1, spanning all floors of the underground floor, and if necessary, installed directly inside the underground continuous wall 1. It is constructed in addition to this (see Figures 1 and 2).

Column 2 is constructed of reinforced concrete, steel frame, steel reinforced concrete, steel frame concrete, etc., depending on the scale of the building, etc., and its cross-sectional shape may be rectangular or circular in addition to the cruciform cross-sectional shape shown in the figure. (See Figures 1 and 3)
.

(Construction of floor slabs) Floor slabs 3.4 and 5.6 for each floor are individually constructed on the ground surface within the underground continuous wall 1 according to the number of basement floors.

Floor slabs 3, 4, 5, 6. Although it varies depending on the scale of the building, etc., it is constructed using PC concrete boards or cast-in-place concrete.

In addition, if the floor area is quite large, install beams 7 such as steel beams, PC beams, or reinforced concrete beams at appropriate positions (
(See Figures 5 and 9).

■ (Excavation of the ground) Excavation shall be carried out using the conventionally widely used excavation method, and the ground immediately below floor slabs 3.4 and 5.6 shall be dug gradually over the entire area (2nd (see figure)
,.

Note that the floor slabs 3, 4, 5.6 are provided with several entrances and exits 8 for carrying in equipment during ground excavation and for discharging excavated soil (see Figure 1).

■(Lift-down of floor slabs) Lift-down of floor slabs 3, 4, 5.6 shall be carried out in parallel with the excavation of the ground (see Figure 2).

A plurality of jacks 9 and a plurality of rods 10 are used for the work (see FIGS. 6 and 7).

Ja-7ki 9 is constructed vertically and horizontally on the floor of the first floor above ground using underground continuous walls 1 and pillars 2 as supporting parts, and a platform 12 is placed on top of the beam 11 at approximately right angles thereto. The receivers are installed on both sides of the stand 12 (see Figures 6 and 7).

Further, the rod 10.10 is connected to the left and right jacks 99, respectively, and a bracket 1 is attached to the lower end of the rod 10.10.
Install 3 horizontally.

Then, on top of the bracket 13, the floor slab 3,4°5.6
Lay them on top of each other and hang them.

In addition, the number and installation location of jacks 9 and rods 10 are as follows:
It shall be determined appropriately based on the size and weight of the floor slabs 3, 4, 5, 6.

In such a configuration, by operating the jacks 9, 9, the floor slabs 3, 4, 5.6 are gradually lifted down to the installation position of the floor slab between basement and floor, and the installation position where even the floor between basement and floor is installed. When it reaches -, stop.

Then, the floor slab 3 of the basement floor is connected to the underground continuous wall 1 and the pillars 2.
It is integrally joined to the side part of.

When the joining of the floor slabs 3 is completed, excavation is started again and the other floor slabs 4, 5, 6 except the floor slab 3 are gradually lifted down to the floor slab installation position on the second basement floor (see Fig. 2).

When you reach the floor slab installation position on the second basement floor, stop at -
Next, the floor slab 4 is integrally joined to the sides of the underground continuous wall 1 and the columns 2.

Thereafter, in the same manner, the floor slabs 5 and 6 are gradually lifted down in parallel with the excavation and joined to the floor slab installation positions on the third and fourth basement floors, respectively.

The floor slabs 3, 4, 5.6 of each floor and the underground continuous walls 1 are joined by the method shown in FIGS. 3 and 4.

To explain the details, a support beam 14 made of reinforced concrete or steel reinforced concrete is constructed horizontally and continuously in the circumferential direction of the underground continuous wall 1, and one method slab 3.4.5. A concave and convex shaped cotter 15 is formed on the peripheral edge of 6.

Then, the peripheral edges of the floor slabs 3, 4, 5.6 of each floor are placed on the support beams 14, and the underground continuous wall 1-&floor slab 3,
4, 5.6 are integrated by filling concrete 16 between them.

Further, the floor slabs 3, 4, 5.6 of each floor and the columns 2 are joined by the method shown in FIGS. 3 and 4.

To explain the details, a bracket 17 is attached to the side of each pillar 2.
A joint fitting 18 is protruded from the end of the floor slab 3°4.5.6 on each floor.

Then, attach the floor slabs 3, 4, 5.6 of each floor to the bracket 1.
7, and the joining fitting 18 is integrally joined to the bracket 17 by welding or bolting.

As another method, the bracket 1-17 may be omitted, the shear bolt 1-19 may be provided protruding from the end of the floor slab, and the shear bolt 19 may be fixed to the beam 7 with the fixing nut 20 (see Fig. 8). ).

If the floor slab is provided with beams 7, please refer to Figures 5 and 9.
The beams 7 are joined to the side surfaces of the underground continuous walls 1 and columns 2 by the method shown in the figure.

To explain the details, the figure shows a joining method when both the column 2 and the beam 7 are made of steel frame materials. The ends of the beams 7 are connected to the metal fittings 21 by bolting them.

FIGS. 10 to 15 show another construction method, which will be explained step by step below.

■ First, construct the underground continuous wall 1 in exactly the same manner as the previous construction method (see Figure 1O).

■ Next, the framework for all basement floors will be constructed on the ground surface surrounded by underground walls I.

In the diagram, number 2 is the pillar, number 3, 4.5 is the floor slab of each floor,
Number 22 is the outer wall, and number 23 is the foundation.

■Next, we will gradually excavate all of the basement floors just constructed below the ground level directly under the frame using what is called underwater excavation, without draining the entire area.

Excavation of the ground will be carried out mainly by jet water, and excavated soil will be removed by dredging.

Also, be careful not to incline the diaphragm wall 1 toward the excavation side by constantly pouring water up to the ground level (see Figure 14).

In parallel with this excavation work, all basement floors will be lifted down.

To lift down the basement floor, a plurality of jacks 9 and a plurality of rods 10 are used as in the previous construction method.

The jack 9 is installed at the upper end of the underground continuous wall 1 on a stand 12, and the rod 10 is connected to the jack 9.

Further, a bracket 13 is horizontally protruded from the lower end of the basement floor, and the lower end of the rod 10 is connected to this bracket I3 to suspend the entire basement floor.

In addition, the number and installation location of jacks 9 and rods 10 are as follows:
It shall be determined appropriately based on the size and weight of the floor slabs 3, 4, 5, 6 (see Fig. 14).

In such a configuration, the underground portion is gradually lifted down by operating the jack 9.9 until it is completely submerged below the ground surface.

Once the basement floor installation is complete, the basement floor is completely fixed into the ground by filling the surrounding area of the basement floor and the underside of the foundation slab with grouting material such as concrete.

The method of adjusting the anchorage (including positioning) on the basement floor after the underground floor is submerged is to use a wire using the underground continuous wall as a reaction force, to use the buoyancy of an air bag, or to adjust the anchorage to a table using a column jet, etc. One possible method is to level the ground in a shape.

Then, when the grout material has developed sufficient strength, it is drained.

Note that, similar to the previous construction method, the foundation slab 23 is provided with several entrances and exits 8 for carrying in equipment and discharging excavated soil during ground excavation.

Further, guide rollers 24 are provided around the outer periphery of the basement floor so that the underground portion can descend smoothly in a horizontal state.

〔Effect of the invention〕

■ Since the floor slabs or floor slabs and their beams for each floor of the underground section are all constructed above ground, quality, safety and work efficiency can be significantly improved.

■ During construction, the floor slabs on each floor are also used as pile-stopping materials for cut beams, raised-backs, etc., so there is no need for the conventionally required pile-stopping materials such as beam-cut beams, raised-backs, etc., and their assembly. Therefore, it is possible to reduce the cost of temporary construction materials and shorten the construction period.

■ Since ground floor construction can be carried out in parallel from the initial stage of underground construction, the overall construction period can be shortened.

■Furthermore, by pre-improving the ground on the surface of the flooring and stopping water, water treatment during underground excavation becomes extremely easy, improving work efficiency and safety.

[Brief explanation of drawings]

1 to 9 show an embodiment of the invention as claimed in claim 1, in which FIG. 1 is a plan view of the basement floor of a building;
The figure is a vertical cross-sectional view during construction, Figure 3 is a partially enlarged plan view of the basement floor, Figures 4 and 5 are vertical cross-sectional views, and Figure 6 is a vertical cross-sectional view of the construction.
The figure is a plan view of the basement floor part under construction, Figure 7 is a partially enlarged side view, Figures 8 and 9 are plan views of the joint between the floor slab and columns, and Figures 10 to 15. 10 to 13 are process diagrams showing the construction method, FIG. 14 is a vertical cross-sectional view of a part of the basement floor structure, and FIG. The figure is a plan view thereof. l... Underground continuous wall, 2... Column, 3.4, 5.6... Floor slab, 7... Beam, 8...
Entrance/exit, 9...jazz, lO...mouth, de, 11
...The receiver is a beam, 12...The receiver is a stand, 13...The bracket,
7, I4...The support is a beam, 15...Cock 16...Concrete, I7...Bracket, 18
...Joining metal fitting, 19... Shear bolt, 20... Fixed nand, 21... Joining metal fitting, 22... Outer wall, 23
...Basic, 24...Guide roller. ('r') Figure 14 Figure n Figure Figure 15 Figure]] Figure

Claims (2)

[Claims] (1) Construct an underground continuous wall around the outer periphery of the underground floor to be constructed, then construct columns for the underground floor inside the underground continuous wall, and then construct the floors of each basement floor above ground. Construct a slab, then lift down the floor slab while excavating the area below the ground surface surrounded by the underground continuous wall, and fix it to the underground continuous wall and columns at the floor slab installation position of each floor. A lift-down underground structure construction method characterized by installation. (2) Construct a continuous underground wall around the outer periphery of the underground floor to be constructed, then construct a frame that spans all floors of the underground floor above ground, and then build the ground surface surrounded by the continuous underground wall. A lift-down underground structure construction method characterized by lifting down all floors of the basement floor while excavating the following parts underwater.