JPS601451B2 - Water stop mountain stop wall construction method using Benoto pile excavator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the provision of a water stop pile construction method, a so-called sea cant pile construction method, using a novel pot pile excavator.

Seacant means secant or cut.
The pile construction method is a method of constructing cast-in-place reinforced concrete earth retaining walls by constructing Benoto-style piles in succession.

This earth retaining wall has no effect on adjacent structures, and the required strength can be freely set, making it extremely reliable.
It has the advantage that it is easy to fix some or all of the pyas on the support layer and also serve as a support pile, so it has been adopted in the water-stopping mountain wall construction method. There is.

The construction procedure for this pia is (1) Provide a base point that can constantly check [square row arrangement].

(0) Equip the swinging pet of the Benoto machine with a sliding tube guide.

This tube guide is capable of supporting the vicinity of the end of the casing tube, and has a structure that allows it to be press-fitted while ensuring verticality. (m) Place the Benoto machine horizontally in the specified position and erect the casing tube, aligning it accurately [with the columns].

(W) Correct the verticality of the casing tube by carefully checking it 2 to 3 times before press-fitting it.

If it is pressed in any further, it will be difficult to correct it. (V) Subsequent construction procedures will be based on the Benoto method, including casing and
Repeat the rocking of the tube, insertion, and digging with a hammer/grab to excavate to a specified depth.

A reinforcing cage was erected and the construction was quickly carried out using the tremie method.
Concrete was poured and the construction of Pya was completed. As shown in Figure 1 A, B, and C, there are various ways to arrange the piers, including staggered, linear overlap, and tangential types. Build one block consisting of textbooks as indicated by the numbers, connecting them in succession, and then move on to the next block.

Among these, especially for the straight-line overlap type, when excavating the intermediate pits such as ■, ■, the existing adjacent piers must be scraped, so Although there is the disadvantage that it will be difficult to dig the trench if it is not done while the water is still young, since it is wrapped, this method is the best in that it can be expected to create a completely watertight wall. Overall,
Regarding the construction procedure for the row of pya columns, as mentioned in the section on the formation of the types of secant pile construction methods, after the construction of pyas such as ■, ■, ■, intermediate pyas such as ■, ■ are immediately constructed to complete one block. Therefore, in this case, when excavating intermediate trenches such as ■ and ■, the adjacent existing pits such as ■, ■, and ■ may be cut, so construction should be done before the concrete has completely hardened. There must be.

Therefore, it is necessary to add a curing retarder to the concrete and adjust the curing time, and at the same time, special attention must be paid to continuous construction in the shortest possible time, which is a difficult point. be.

This construction method is particularly suitable when there are a large number of underground obstructions such as pine piles deep underground.

In other words, some obstacles in relatively shallow areas can be relatively easily removed by temporarily installing a mountain stop, grasping the exposed head of the underground obstacle, and pulling it out. Although it is possible to construct a retaining wall, it is necessary to construct it deep underground (GL
-low degree), it is practically impossible to treat them with the construction described above.

In order for workers to descend to the bottom of the borehole to grasp underground obstacles, treatment must be taken to prevent the walls of the borehole from collapsing. Whereas the work is necessarily exaggerated and disturbs the strata, in the seacant pile method, the casing tube prevents the wall of the candle hole from collapsing, so no additional treatment is required. This is due to the fact that the operator can descend into the casing tube and carry out the gripping operation without any trouble.

However, problems arise after removing the underground obstruction.

In other words, if concrete is placed in the void left by removing underground obstructions, the resulting piers will not be the same as planned, but instead will be irregularly shaped piers with protrusions protruding beyond the surface. However, this protrusion becomes an obstacle to excavation when constructing an adjacent pit later. The present invention has been made in view of the above points, and its gist is that an inner casing is inserted into a casing tube with a hole made by a Benoto machine, and the inner casing is inserted into the casing tube. concrete is poured, and the outer periphery is backfilled with waterproof soft hardening material (K-soil, soil concrete, etc.).
The pit is constructed of a double layer with the outer periphery wrapped in a soft material, and this outer layer is overlapped so that the hole is drilled by a Benoto machine for constructing the adjacent pit.

Hereinafter, details of the present invention will be explained based on the drawings. The construction procedure of the construction method of the present invention is shown in the plan and longitudinal front views of Figure 2, in which step (1) is the state in which the digging by the Benoto machine has been completed, and 1 in the figure is the casing tube. . In step (B), the inner casing 2 is inserted into the casing tube, and 3 in the figure is a bag for preventing concrete leakage that is preferably attached to the lower end of the inner casing 2.

In step (m), the outer periphery of the inner casing 2 is coated with a water-stopping material such as stabilizing liquid + water glass or soil concrete, and base/
backfilling with a soft hardened material 4 strong enough to be cut in a machine;
This is a mode in which the casing tube 1 is being pulled out.

Step (N) is a mode in which concrete 5 is poured into the inner casing 2 in a tremie step and the inner casing 2 is pulled out, and 6 in the figure is a tremie pipe. Note that the inner casing 2 may be buried and left without being pulled out. Step (V) shows a mode in which the above-mentioned pia construction process is repeatedly carried out while wrapping the outer layer part, and the pia is made continuous.

Since the construction method of the present invention has the above-mentioned configuration, it not only eliminates the need for rapid continuous construction during uncured work and consideration of curing retarders when rapping with existing piers, as in the conventional method, but also eliminates the need for consideration of curing retarders. In the case of moderate failure, only the soft outer layer is cut away when constructing the adjacent piers, and the concrete IJ core part is molded into a regular shape by the inner casing 2 and will never protrude. There are no problems with drilling.

[Brief explanation of the drawing]

Fig. 1 shows rows of pillar columns of various formations in the sea cant pile construction method, and Fig. 2 is a construction procedure diagram of the construction method of the present invention. Brief explanation of symbols, 1...Casing tube, 2
... Inner casing, 3... Concrete leakage prevention bag, 4... Soft hardening material, 5... Concrete,
6...tremie tube. Puta/Sardine is Z Sardine

Claims (1)

[Claims] 1. The inner casing shall be inserted into the casing tube of the hole drilled with a Benoto machine, and concrete will be placed inside it, while the outer periphery will be backfilled with water-stopping soft hardened material. A water stop mountain stop wall construction method using a Benoto pile excavator, characterized in that the pier is constructed in a double layer with the outer periphery wrapped in a soft material, and the adjacent pier is constructed by overlapping with this outer layer part.