JPS5916622B2 - Underground tank construction method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention primarily relates to an underground tank for storing liquids, such as liquid fuel, clean water, and the like.

When storing liquid, if the head is made smaller, the structural strength of the specimen does not need to be increased so much, but if the installation area is limited, the height of the tank must be increased.

However, if the tank height is increased and the head becomes larger, the load placed on the sample will inevitably become extremely large. Therefore, in recent years, the idea of constructing a specimen underground and making the pressure inside the tank resist the ground has been born.

In this case, it is only necessary to consider the compressive force on the specimen,
Concrete segments with excellent compression resistance can be used, and if corrosion protection is complete, the inner metal layer can be thinner, among other advantages. In order to construct such underground tanks more economically and increase their structural strength, it is effective to use segments that can be obtained relatively inexpensively; However, this problem has to be overcome, and this problem must also be resolved at the same time.

Based on the above-mentioned viewpoints, the present invention provides a method for constructing an underground tank that can obtain a tank body with a large compressive strength while using segments that can be obtained economically. A sheath is embedded in the specimen in advance, and at appropriate times during the construction process, adjacent segments are tightened using the tension of the steel wire inserted through the sheath, and press dressing is applied.The completed specimen is entirely vertical and horizontal. It is characterized by having a very large internal stress in the direction.

Hereinafter, the present invention will be explained by way of a first embodiment with reference to the accompanying drawings.

First, in practicing the invention, a segmented port shown in plan view in FIG. 1 and in side view in FIG. 2 is used.

This segment 1 has an H-shaped planar shape on both left and right end surfaces, and when arranged in an annular shape so as to obtain the desired diameter of the tank wall body 2 as shown in FIG. It is beveled to allow for Furthermore, segment 1
A vertical sheath 3 and a horizontal sheath 4 are embedded in the flange of the segment 1 near the four corners, and two vertical sheaths 3 are embedded in the web of the segment 1. The segments 1 are reinforced concrete blocks arranged on the ground in a ring shape as shown in FIG. Additionally, it is compressed. This compression work may be performed at any time after the arrangement of two or more pieces is completed. That is, the steel wires 5 may be tightened in batches of several pieces, and the steel wires 5 may be tightened using appropriate fittings or welded to prevent loosening of the steel wires 5, or may be tightened after the steel wires 5 are arranged in an annular shape. The second stage is assembled while the first stage is being assembled or after the first stage has been assembled.

In this case as well, the vertically adjacent ones are pressed together by the steel wire 6 inserted through the sheath 3 and press dressed, and the tensioned steel wires 6 are brought into a tensioned state by appropriate means as in 5. shall be maintained. After completing the assembly of the required number of stages or all stages as described above, the earth and sand inside the ring is excavated and the whole is gradually settled.

Once it has been sunk to the required depth, the work will be carried out using conventional methods, including lining with a metal layer and installing a membrane. Incidentally, when assembling the segment 1, the cavity 7 of the segment is filled with mortar, etc., according to a conventional method. The construction is completed by providing a roof (not shown) on the layered wall body 2 constructed as described above and attaching incidental equipment.

As is clear from the above description, according to the present invention, regardless of whether or not the segment is made of PS concrete, press dressing is performed by applying a tensile force to the steel wire inserted through the sheath. Since each adjacent segment is compressed in the state in which the steel wires are applied, the entire tank wall body 2 is tightened in two directions vertically and horizontally by steel wires, giving maximum compression resistance and being constructed in the form of a relatively inexpensive reinforced concrete block. A strong underground tank can be obtained using the segments.

In particular, according to the present invention, since the segment 1 has an H-shaped plane, it is not only extremely lightweight and strong, but also the upper and lower surfaces of the segment 1 are large flat surfaces, so that the second stage is placed above the first stage. When assembling the tiers, the surface area of the upper and lower parts that make surface contact with each other is large, making it easy to mount the tiers.Thus, these factors make it extremely easy to assemble on-site, and of course the overall structure is more robust after assembly. Become something. In addition, since the segments 1 are made H-shaped and a cavity 7 is formed at the joint between the segments 1, and this cavity 7 is filled with a filler such as mortar, the liquid at the joint between the segments is Tightness and high connection strength are obtained, which fundamentally solves the inherent drawbacks of the method of assembling the tank wall body using a large number of segments.
Furthermore, since at least the second stage is assembled and press-dressed vertically and horizontally before it is submerged, it is not only resistant to radial inward earth pressure but also to vertical bending during submersion. Strong enough. In this case, in particular, since sheaths in both the vertical and horizontal directions are embedded in the flanges located at the four corners of the segment 1, the flange parts are reinforced by the steel wires 5 and 6 inserted through these sheaths. Each of the segments, and even the entire segment, is sufficiently reinforced and contributes to the improvement of the above-mentioned resistance force.

[Brief explanation of the drawing]

Fig. 1 is a plan view of an embodiment of the segment used in carrying out the present invention, Fig. 2 is a side view, Fig. 3 is a plan view of the tank wall body with some parts omitted, and Fig. 4 is an explanation of assembly. It is a diagram. 1... Segment, 2... Tank wall body,
3, 4... Sheath, 5, 6... Steel wire,
7... Blank space.

Claims (1)

[Claims] 1 Segments made of reinforced concrete blocks that form an H-shape in plan, with vertical and horizontal sheaths embedded in the flanges located at the four corners, and vertical sheaths embedded in the central web, are arranged horizontally in a ring, and each adjacent The first stage, which is part of the main body of the tank wall to be constructed, is assembled by prestressing and integrating the segments by tensioning the steel wires inserted through the transverse sheath, and then the upper part of the first stage is assembled. Segments similar to the above-mentioned segments are placed and arranged in an annular manner, and a prestress is applied by tensioning a steel wire inserted through the transverse sheath of each adjacent segment to integrate them to assemble the second stage. The segments of the first stage and the first stage are integrated by applying prestress by tensioning the steel wires inserted through their longitudinal sheaths, and then the third stage and subsequent stages are assembled in the same manner as the second stage. After constructing the tank wall body and assembling at least the second stage, it is sunk into the ground using the well construction method, and at the same time, the voids formed at the joints between the segments are filled with filler such as mortar. Characteristic underground tank construction method.