JPH0347319A - Permeable pipe kettle equipment and excavation 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 (Field of Industrial Application) The present invention relates to the structure of a kettle for pumping up groundwater accompanying excavation work at a construction site, and an excavation method using the same.

(Prior art) Generally, during excavation work at a construction site, if the water level around the ground is higher than the base of the root cut, water accumulates at the bottom of the root cut, and the flow of water causes water to flow into weak areas of the root cut. The flow gathers and eventually becomes like it has scoured the nearby ground. This phenomenon is called a piping phenomenon, and the root truncation becomes sludge, making it difficult to excavate.

In such cases, it is preferable to construct a cut-off wall before excavating, but there are problems in terms of construction period and cost, and to deal with this, the horizontal sheet pile method is adopted. Furthermore, prior to the excavation, a winter period was set aside for all the water to be pumped up and drained to the surface using submersible pumps.

In this winter, for example, as shown in Figure 6, the root truncation is 20.
A required hole 21 is drilled in the hole 21. Then, a drum 23 wrapped with a water-permeable mat 22 is installed in this hole 21. A plurality of water passage holes 23a are bored in order to collect surrounding water. Water 24 stored in this drum 23
A drainage pipe 26 is provided with a submersible pump 25 for draining water.
The water 24 is drained to the ground. In this way, the water permeable mat 22 prevents the intrusion of fine sand and silt into the underground water, allowing only the water to collect in the drum 23 and draining the water using the submersible pump 25. There is.

(Problem to be Solved by the Invention) By the way, in the above-mentioned conventional winter area 27, even if the drum 23 is buried in the hole 21 when making the winter area, buoyancy is exerted by the water already accumulated at the bottom of the hole 21, It is difficult to embed the drum can 23, and furthermore, the water-permeable mat 22 gradually becomes clogged, and eventually the surrounding water starts to enter the drum can 23 as shown by the solid line arrow in FIG. , an intrusion state occurs as shown by the broken arrow, and fine sand, silt, etc. enter the drum can 23 from above. Therefore, the submersible pump may become clogged, and in some cases, the water may be buried during the winter. In addition, recently, there has been a decrease in the number of specialized earthworks that perform winter construction and management, making it difficult to use the winter excavation method, and alternative drainage methods such as deep wells and well points. However, the disadvantage was that the construction was extensive and costly.

The object of the present invention has been made in view of the above-mentioned drawbacks.
It is an object of the present invention to provide a winter excavation method that is easy to perform construction, prevents clogging due to inflow of earth and sand, and can be used in this winter.

(Means for Solving the Problems) The gist for solving the above-mentioned problems and achieving the purpose of the permeable pipe in winter according to the present invention is to install a water collection pipe and a water collection pipe to the water collection pipe in a hole drilled at the bottom of the root cut. In winter, a filter that prevents the intrusion of earth and sand is wrapped around the water collection pipe and buried, and the water around the ground that collects in the water collection pipe is drained to the ground using a submersible pump installed inside the water collection pipe. , a pedestal for mounting a submersible pump is formed at the bottom of a cylindrical reinforcing cage provided with a hook for transportation, and a concrete water permeable pipe is installed in the reinforcing cage.

The gist of the excavation method according to the present invention to solve the above-mentioned problems and achieve the purpose is to divide the root cut into a plurality of locations, drill holes at predetermined locations, and create a hook for transportation. A pedestal for mounting a submersible pump is formed at the bottom of a cylindrical reinforcing cage provided with a water pump, a water permeable pipe winter device consisting of a concrete water permeable pipe installed in the reinforcing steel cage is buried in the hole, and the water permeable pipe is installed in the hole. The water collected in the winter device is drained by a submersible pump, the ground of another section from which the water has been drained is excavated, and the water is drained by installing the permeable pipe winter device, and the water is drained by this. It consists in repeating alternately excavating other sections.

(Function) As described above, according to the permeable pipe winter device of the present invention, the surrounding water in winter enters and accumulates inside the concrete permeable pipe, and this water is drained to the ground by the submersible pump. Ru. Furthermore, since the reinforcing bar cage is provided with a hook for transportation, it can be lifted up with a wire or the like and moved to another drainage location.

Furthermore, since the reinforcing bar cage is provided with a pedestal, by placing the submersible pump on this pedestal, mud is not directly sucked in from the suction port of the submersible pump, and a decrease in the drainage capacity of the submersible pump can be prevented. .

Furthermore, since a reinforcing bar cage is used, when the cage is buried in a hole drilled in the bottom of the root cut, it is not affected by the buoyancy of water accumulated in the hole.

According to the excavation method of the present invention, the permeable pipe winter device is installed in the winter prior to excavation work to drain water around the ground at the bottom of the root cut, so that the permeable pipe winter device is installed in a section other than the section where the permeable pipe winter device is installed. Drainage treatment is carried out in the section, allowing the water level to be lowered from the bottom of the cut, allowing the excavation work in this section to proceed smoothly.

By performing this funeral hall installation work and excavation work alternately,
This means that excavation work can be carried out without being hindered by groundwater.

(Example) Hereinafter, an example of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a longitudinal sectional view of a permeable pipe winter device 1 of the present invention. In the figure, 2 is a reinforcing cage, 3 is a concrete water permeable pipe, 4 is a bottom cut during excavation work, 5 is a hole drilled for winter use, and 6 is a submersible pump for drainage.

The water permeable pipe 3 is made of concrete, and its water permeability is as follows:
The permeability coefficient is 2.0 cm/sec, and the porosity is 32%. Note that this is just one example, and the hydraulic conductivity is 0.
5~2.0cm/sec+ The porosity is 20~32
%, the object of the present invention can be achieved.

FIG. 2 is a front view including a longitudinal cross-sectional view of this water permeable pipe.

As shown in FIGS. 3 and 4, the reinforcing bar W2 has a substantially cylindrical shape as a whole, and circular flat pars 7.8 are arranged above and below, and a plurality of circular flat pars 7.8 are arranged on the outer periphery of the flat pars 7.8. The flat pars 9 and 10 for the side walls are brought into contact with each other and welded to integrate them. The flat pars 9 and 10 are bent to form a pedestal 11 for mounting the submersible pump 6.

Further, a reinforcing circular reinforcing bar 12 is welded to the middle of the flat par 7.8. This reinforcing circular reinforcing bar 12 is not limited to one, but a plurality of reinforcing bars 12 may be welded to the flat bars 9 and 10.

Further, at the upper end of the flat parr 9.10, hooking portions 13.13 for transporting the reinforcing bar cage 2 are formed with curved portions.

In this way, the water permeable pipe 3 is placed in the reinforcing bar cage 2,
As shown in FIG. 1, this permeable pipe winter device 1 is used by being suspended by wires 14 and 14 and buried in a hole 5 drilled in the root cut 4. That is, water around the ground enters the permeable pipe 3 of the permeable pipe winter device 1, and this stored water is sucked into the main body of the submersible pump 8 through the suction port 6a of the submersible pump 6, and is then pumped through the drain pipe 6b. It drains water above ground.

Next, the excavation method of the present invention using this permeable pipe winter equipment 1 will be explained. In this excavation method, as shown in the steps in Figures 5 (a) to (d), first, the root cut 4 in the excavation work is divided into two sections, and the section to be drained is one step deeper. (Dig down and drill a hole 5 for winter use.Then, the permeable pipe winter device 1 is buried in this hole 5, and the water around the ground is drained by the submersible pump 6.The water level Excavate in the other section where the area is lowered.

After excavating to the same level as the permeable pipe winter device 1, a winter hole 5a is subsequently drilled (see FIG. 5(b)), and the permeable pipe winter device 1 is removed from the hole 5 using a crane. etc. (not shown) and move it, and bury it in the hole 5a. Then, the accumulated water is drained by the drain pump 8,
A section in which the water-drained hole 5 is provided is excavated.

In this way, the construction of the funeral hall and the excavation work are repeated alternately, and the area to be excavated is always drained of water, making dry work possible.

In this embodiment, the area is divided into two sections, but it may be further divided into two or more sections and the winter installation and excavation work may be carried out sequentially.

Although one embodiment of the present invention has been described above, it is needless to say that the present invention is not limited to this and can be modified as appropriate without changing the gist.

(Effects of the Invention) As explained above, a pedestal for mounting a submersible pump is formed at the bottom of a cylindrical reinforcing cage provided with a hook for transporting the permeable pipe in winter, and the reinforcing steel In addition, the excavation method according to the present invention involves installing a concrete water permeable pipe in the broom, dividing the bottom of the cut into multiple locations, drilling holes at predetermined locations, and creating a hook for transportation. A pedestal for mounting a submersible pump is formed at the bottom of the provided cylindrical reinforcing cage, a water permeable pipe winter device consisting of a concrete water permeable pipe installed in the reinforcing steel cage is buried in the hole, and the water permeable pipe funeral home is installed. Draining the water collected in the device with a submersible pump, excavating the ground of another section from which the water was drained, installing the permeable pipe strain field device and draining the water, and draining the water by this. Since we decided to alternately repeat excavating other sections, we have the following effects.

■ First, since the outer wall of the permeable pipe strain field device is made of reinforcing steel,
When burying this permeable pipe strain field device, there is no buoyancy due to the water stored in the drilled hole (the burying work is easy).

■ There is less clogging caused by sediment, etc., as in conventional systems, and adverse effects such as clogging of submersible pumps due to inflow of sediment are also reduced.
In addition, the work required to remove earth and sand that has flowed into drum pipes, etc., as required in the past, has been reduced.

(2) The permeable pipe strain field device of the present invention is provided with a hook at the upper end of the reinforcing bar, making it easy to relocate.

■ Since water is drained using a permeable pipe strain field device and the area from which the water has been drained is excavated, the excavated surface will not become sludge and the efficiency of excavation work can be improved.

■ The permeable pipe strain field device has a simple structure and is lightweight, which reduces costs and facilitates handling.

In this way, we have been able to provide a valuable permeable pipe strain field device and excavation method.

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view of the permeable pipe strain field device of the present invention, Fig. 2 is a front view of the concrete permeable pipe, Fig. 3 is a longitudinal cross-sectional view of the reinforcement capacity, and Fig. 4 is the same. The plan view and FIGS. 5(a) to 5(d) are explanatory diagrams of an excavation method using the permeable pipe strain field device of the present invention, and FIG. 6 is a longitudinal sectional view of the conventional strain field device. 1... Permeable pipe strain field device, 2... Reinforcement capacity, 3... Concrete water permeable pipe, 4... Root truncation, 5... Hole, 6
...submersible pump, 7, 8. 9. 10...Flat bar, 11...
- Pedestal, 12... Circular reinforcing bar, 13... Hanging part. Figure 1 Figure 8 Figure 2 Figure 4 Cause

Claims (2)

[Claims] (1) Wrap a water collection pipe around the hole drilled in the bottom of the root cut, and a filter that prevents dirt, etc. from entering the water collection pipe;
In a kettle system in which these are buried and water around the ground collected in the water collection pipe is drained to the ground using a submersible pump installed in the water collection pipe, a cylindrical reinforcing bar with a hook for transportation is provided. A pedestal for mounting a submersible pump is formed at the bottom of the basket,
A permeable pipe kettle apparatus characterized in that a concrete permeable pipe is installed in the reinforcing cage. (2) The cut bottom is divided into multiple locations, holes are drilled at predetermined locations, and a pedestal for mounting a submersible pump is placed at the bottom of a cylindrical reinforcing cage with hooks for transportation. A permeable pipe boiler device comprising a concrete water permeable pipe installed in the reinforcing cage is buried in the hole, and the water collected in the water permeable pipe kettle device is drained by a submersible pump. The method is characterized by alternately repeating the steps of excavating the ground of another section from which the water has been drained, installing the permeable pipe boiler device to drain the water, and excavating the other section from which the water has been drained. Excavation method.