JPS5810560B2 - Plug construction method for bedrock shafts - Google Patents

Description

[Detailed Description of the Invention] When forming a horizontal concrete plug in the shaft of an oil storage tank in bedrock, the conventional method is to widen the position of the shaft where the concrete plug is to be installed by blasting, and then It is formed by placing shoring material from the bottom of the hole, building a formwork on top of it, and pouring concrete.
This method has drawbacks such as the work involved in assembling the shoring material from the bottom of the horizontal hole and the need for a large amount of shoring material.

In view of these drawbacks, the present application was invented to enable easy and quick construction.In order to explain one embodiment, the shaft 1 is excavated and the position where the concrete plug 2 is to be installed is determined. After expanding by blasting 1 to form a recess 3, several rock anchors 5 for fixing the pedestal concrete 4 are driven diagonally downward, and the upper ends of the rock anchors 5 are slightly protruded, and then the pedestal concrete 4 is The formwork 6 is suspended from above or framed using a simple ladder, the formwork 6 is supported by supports 7, and concrete 8 is poured into the formwork 6 in the recess 3. A pedestal 4 with a stepped portion 9 is formed, a precast concrete slab 10 is suspended and fitted onto the stepped portion 9, and if the shaft 1 is large, the precast concrete slab 10 is divided into two or three parts as necessary. It is also possible to fit them together.

Thereafter, reinforcing bars 11 are assembled on the precast concrete slab 10, and concrete 12 for the plug is poured to form the concrete plug 2.

The pedestal 4 may or may not have the stepped portion 9.

Since the present application is constructed as described above, it can be easily constructed without requiring large-scale shoring materials, so the construction period is short and the construction is easy.

In this application, after excavating a vertical shaft diagonally upward, the location where the concrete plug is to be installed is widened by blasting, and then rock anchors to fix the pedestal concrete are driven around the shaft, the pedestal concrete is poured, and the upper end of the rock anchor is In addition to integrating the pedestal and the pedestal, a precast concrete slab is laid on the pedestal, reinforcing bars are assembled on the precast concrete slab, and then concrete for the plug is poured, making construction easy and the construction period short. Made of
It has the advantage of not requiring any shoring material and can reduce construction costs accordingly.

[Brief explanation of drawings]

Figure 1 is a sectional view of the entire oil storage tank, Figure 2 is a sectional view of the assembled formwork before forming the pedestal, Figure 3 is a sectional view of the pedestal formed, and Figure 4 is a sectional view of the plug. It is a sectional view of a state in which it is formed.

Claims (1)

[Claims] 1 After excavating the shaft, expand the location where the concrete plug is to be installed by blasting, then drive rock anchors to fix the pedestal concrete around the shaft, pour the pedestal concrete, and unite the top end of the rock anchor with the pedestal. At the same time, this plug construction method for a rock shaft is characterized in that a precast concrete slab is laid on the pedestal, reinforcing bars are assembled on the precast concrete slab, and then concrete for the plug is poured.