JPH0432170B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for constructing an underground structure using an underground continuous wall.

(Prior Art) Underground continuous walls are used not only as temporary water-stop walls and retaining walls, but also as underground structures.

When using a diaphragm wall as an underground structure,
Conventionally, after constructing an underground continuous wall, the inside of the wall is excavated, and post-cast structures such as columns, beams, and floor slabs are constructed on the inner surface of the continuous wall, and these are joined to the continuous wall to integrate them.

This is due to the following reasons. In other words, since the underground continuous wall is constructed for each unit wall, there are joints between the unit walls, but at the joint, the horizontal reinforcement of the reinforcing bar cage in the leading wall is used as a joint member to protrude from the partition plate to the trailing wall. , overlaps with the horizontal reinforcement of the reinforcing bar cage on the trailing wall. In this overlapped part, the transverse bars cannot be integrally connected to each other, nor can they be restrained by restraint bars, so the joint is vulnerable to out-of-plane shear forces that act from the ground side after excavation. Columns and beams are constructed on the inner surface as a post-cast framework, and the out-of-plane shear force is borne by these columns and beams.

(Problems to be Solved by the Invention) However, the conventional construction method of joining the post-casting frame after constructing a continuous wall does not allow for: (2) Since the continuous wall piles, wall columns, and beams are eccentric, a large number of shear connectors are required for joining, which not only increases the construction cost but also lengthens the construction period. 3) The joints between post-cast columns and beams and continuous walls are double-invested with concrete, reinforcing bars, etc.
It had various problems such as being uneconomical.

The object of the present invention is to provide a construction method that can solve the various problems mentioned above.

(Means for Solving the Problems) This invention has discovered a method of integrally joining the horizontal reinforcement of the reinforcing bar cage of the leading wall and the horizontal reinforcement of the reinforcing bar cage of the trailing wall at the joint between unit walls of a continuous wall. Ta. This invention is based on such a method, and includes the steps of inserting and installing a reinforcing bar cage for a column into an excavated first groove, and then constructing a column by pouring and hardening concrete. Reinforcement cages for beams and walls are inserted into the continuous second slots, concrete is poured into the second slots and hardened to construct the beams and walls, and the ends of the reinforcing bar cages for columns and the beams are placed. and a step of integrally joining the ends of the reinforcing bar cage for the wall. According to the present invention, the above-mentioned problem is solved because the continuous wall itself forms columns and beams.

(Example) FIG. 1 is a plan view of an underground structure with underground continuous walls, where A shows a leading wall that becomes a column, and B shows a trailing wall that becomes a beam and a wall.

FIG. 2 shows a reinforcing bar cage assembly 1 for a column, which assembly comprises a pair of partition plates 2, 2 and a reinforcing bar cage 3. As shown in FIG. The partition plate 2 includes a pair of end partition plates 2a arranged in the width direction of the slot, and a pair of corrugated central partition plates 2b arranged in the length direction of the slot. A vertically extending sleeve 4 having a U-shaped cross section is fixed between the partition plate 2b and the partition plate 2b. The sleeve 4 is closed at its lower end and has a flange 5 at its open side end. Reference numeral 20 indicates a protrusion provided on the inner surface of the sleeve, 21 indicates a rib fixed between the sleeves 4, and 22 indicates a concrete leakage prevention sheet.

The column reinforcement cage 3 has hoop reinforcements 3 around the column main reinforcement 3a.
b, and a main beam reinforcement 6 is provided inside, and the end of the main beam reinforcement 6 is fixed to a screw type coupler 7 fixed to the back wall of the sleeve 4. Above assembly 1
will be pre-assembled before construction.

During construction, as shown in FIG.
The lower part of the support layer 9 is made to reach the support layer 9 (see FIG. 5). Next, insert the reinforcing bar cage assembly 1 for the column into the slot 8.
are inserted and installed, concrete is poured between the pair of partition plates 2, 2 and hardened, and the columns 10,
A pile 11 is formed in the lower part (see Figure 5).

Next, a trailing slot 12 continuous with the leading slot 8 is excavated, and a reinforcing bar cage 13 for beams and walls is inserted into this slot 12 as shown in FIGS. 3 to 5. Rebar cage 1
3 is the upper and lower main beam reinforcement 14, and the hoop reinforcement 1 surrounding it
5. It is composed of vertical reinforcements 16 and horizontal reinforcements 17 for walls, and when the reinforcing bar basket 13 is inserted, the ends of the main beam reinforcement 14 and the horizontal reinforcement 17 are inserted into the sleeve 4 from its upper opening. At this time, the stopper plate 18 provided at the end of the beam main reinforcement 14 is fitted into the flange 5 to restrain the flange. 18a indicates a sealing material.

After the reinforcing bar baskets 13 for the walls and beams are erected as described above, concrete is poured into the trailing grooves 12 and hardened. In addition, since the sleeve 4 is filled with stabilizing liquid, high-pressure water is used to clean it and replace it with the stabilizing liquid, and then a high-strength non-shrinkable injection material 19 is injected into the sleeve 4 and hardened. 19
The beam main reinforcements 6 of the column reinforcement cages 3 and the beam main reinforcements 14 of the beam and wall reinforcement cages 13 are integrally joined through the
(see figure). As the injection material, cement-based or epoxy-based materials, such as Master Follow manufactured by Nisso Masters Co., Ltd., can be used.

The ground inside the continuous wall was excavated, and the main beam reinforcement at the center perpendicular to the wall to be connected to the column was connected to the reinforcing bar cage for the column via a coupler that was pre-attached to the reinforcing bar cage (not shown). The slab reinforcements are then joined by bending and stretching.

In the continuous wall as described above, the in-plane shear force acting in the longitudinal direction of the continuous wall is transmitted by the bearing pressure of the corrugated central partition plate 2b and the cotter reinforcements 21, which has been a problem in the past. The tensile stress acting on the beam main reinforcements 6, 14 due to the out-of-plane shear force is transmitted via the sleeve 4, the injection material 19, and the coupler 7, and the beam main reinforcements 6, 14 are integrated by the injection material. Can sufficiently resist out-of-plane shear forces.

In the above embodiment, the columns are the leading walls, and the beams and walls are the trailing walls, but the reverse may be used. In this case, the reinforcing bars for the beams and walls may be provided with partition plates and sleeves. The structure of connecting reinforcing bar cages using partition plates, sleeves, injection materials, etc. can be applied not only to the above-mentioned embodiments but also to cases where conventional continuous wall joints, that is, unit walls are used only for walls.

(Effects of the Invention) As described above, according to the present invention, the columns and beams are formed by the continuous wall itself, so the columns and beams do not protrude from the wall surface or can be reduced in width. , the interior space can be used effectively. In addition, since the center lines of the piles, columns, and beams coincide, there is no eccentric load between the members, resulting in a simple structure, and since shear connectors are not required, construction costs and construction times can be reduced. Furthermore, it is possible to avoid double investment in concrete, reinforcing bars, etc., which is economical.

[Brief explanation of drawings]

Fig. 1 is an overall plan view showing one embodiment of the present invention, Fig. 2 is a plan view of a reinforcing bar cage assembly for columns, Fig. 3 is an enlarged plan view of part A in Fig. 1, and Fig. 4 is the same as above. FIG. 5 is a side view showing the entire reinforcement arrangement, and FIG. 6 is a perspective view showing the opening stop plate. 1... Rebar cage assembly for pillars, 2... Partition plate, 3...
...Reinforcing bar cage for columns, 4...Sleeve, 6...Beam main reinforcement,
8... Leading trench, 10... Pillar, 11... Pile, 12
... Trailing groove, 13 ... Rebar cage for beams and walls, 1
4... Beam main reinforcement, 19... Injection material, 23... Beam, 2
4...Wall.

Claims (1)

[Claims] 1. A process of inserting and installing reinforcing bar cages for columns into the excavated first groove, and then pouring and hardening concrete to construct columns, and installing reinforcement cages for beams and walls into second grooves that are continuous with the first groove. Reinforcement cages are inserted and installed, and concrete is cast and hardened in the second groove to construct beams and walls, and the ends of the reinforcing bar cages for columns and the ends of the reinforcing bar cages for beams and walls are connected. A method for constructing an underground structure using an underground continuous wall, comprising the step of integrally joining the wall.