JP3227215B2 - Bottom plate structure of underground tank and method of construction - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bottom plate structure of an underground tank used for storage of petroleum and liquefied natural gas and the like, and a method of constructing the structure.

[0002]

2. Description of the Related Art As is well known, in recent years, underground tanks buried in the ground have been used as one type of storage tanks for petroleum and liquefied natural gas. 2 and 3 are views showing a conventional underground tank.
Is the bottom version. The bottom slab 1 is composed of a lower first layer 5 and a second layer 6 built on the first layer 5 as shown in FIG. The side surface 6a of the second layer 6 is formed inside the side surface 5a of the first layer 5, and the side surface 5a of the first layer 5, the upper surface 5b of the periphery of the first layer 5, and the second layer Form a crossover portion 7. And
A side wall 2 is formed on an outer peripheral portion of the bottom slab 1, and an upper end 3 of the side wall 2 protrudes above the ground G, and a lid 4 is provided on the upper end 3. Various reinforcing bars are arranged in the first layer 5 and the second layer 6 of the bottom slab 1. FIG. 3 shows a typical reinforcing bar of the bottom slab 1. Crossover main bars 8 are arranged above the peripheral edge of the first layer 5, and horizontal bars are arranged above the second layer 6. .. Are arranged in the direction. And the main part 8 of the crossing part and the upper part 9
Are attached to the oblique lines 10. The oblique streaks 10 are used to increase the strength of the crossover portion 7 by integrating the crossover main bar 8 and the upper streak 9. The lower end of the oblique streaks 10 is located near the side surface 5 a of the first layer 5. And the upper end thereof is located near the upper surface of the peripheral portion of the second layer 6.

In order to construct such a bottom slab 1, various reinforcing bars are arranged, and at the top of the peripheral edge of the first layer 5, crossover main bars 8 are arranged, and these crossover main bars 8. Are connected to each other, and concrete is cast to construct the first layer 5. Thereafter, the upper streaks 9 are arranged, the upper portions of the oblique streaks 10 intersect with the upper streaks 9, and concrete is poured to construct the second layer 6.

[0004]

However, in the bottom plate structure using such oblique lines, it is not easy to arrange the reinforcing bars, and especially when the tank is large and the bottom plate is thick, the above-mentioned upper lines and oblique lines are not provided. There were many bars and it was very difficult to arrange the bars.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a bottom plate structure of an underground tank in which rebar arrangement is easy and a method of constructing the same.

[0006]

According to the bottom plate structure of the underground tank according to the first aspect of the present invention, a rising portion protruding upward is formed at a peripheral portion of the first layer, and the rising portion of the first layer is formed with a rising portion. An upper streak arranged in a substantially horizontal direction with the second layer built inside is bent so as to descend laterally at a peripheral portion of the second layer, and a tip end of the upper streak is a second end. It is a means for solving the above-mentioned problem that it is buried in one layer of the rising portion.

According to a second aspect of the present invention, in the method of constructing a bottom plate for an underground tank, when constructing a first layer having a rising portion at a peripheral portion, an end of the upper streak is bent downward. The object is to construct a first layer in a state in which the end portions are arranged in the rising portion, and then construct a second layer in a state in which the upper muscle is buried on the upper surface of the first layer. To solve the problem.

[0008]

According to the bottom plate structure of the underground tank of the present invention, since the rising portion protruding upward is formed at the peripheral portion of the first layer, the step at the crossing portion is small, and it is arranged on the upper portion of the second layer. By bending the upper streaked line, its end can be arranged in the rising portion of the first layer.

According to the method of constructing a bottom plate for an underground tank according to the second aspect of the present invention, when constructing the first layer having a rising portion on the peripheral edge, a state where the end of the upper streak is buried in the rising portion. Then, the second layer is constructed in a state where the main reinforcement is buried on the upper surface of the first layer, so that there is no difficult arrangement of oblique streaks and the arrangement of reinforcement is easy.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The bottom plate structure of an underground tank according to the present invention and a method of constructing the same will be described in detail below with reference to embodiments. FIG. 1 is a view showing an embodiment of a bottom plate structure of an underground tank according to the present invention, in which reference numeral 11 denotes a bottom plate. This bottom plate 11 has a diameter of about 70 m and a height of about 10 m,
It comprises a lower first layer 12 and a second layer 13 built on the first layer 12. The first layer 12 has a joint surface 12b formed at the same height as that of the related art, and a rising portion 14 protruding upward from the joint surface 12b is formed at a peripheral portion thereof. The second layer 13 is formed inside the rising portion 14, that is, above the joint surface 12 b, and the side surface 12 a of the first layer 12, the upper surface 14 a of the rising portion 14, and the side surface 13 a of the second layer 13 are overlapped. A difference portion 15 is formed.
The first layer 12 and the second layer 13 are provided with various types of reinforcing bars. Typical reinforcing bars include lower bars 16 assembled near the lower surface of the first layer 12 and heightwise. There are a stirrup 17 that is creped, a reinforcing bar 18 that is laid around the second layer 13, and an upper bar 19. The upper streaks 19 are arranged horizontally in the upper part except for the peripheral portion of the second layer 13, and are bent so as to descend sideways at the peripheral portion of the second layer 13, and the distal end thereof is formed. It is buried in the rising portion 14.

Next, a method of constructing the bottom slab 1 will be described. First, the lower muscle 16 ... and the stirrup 17 ...
And the like, and the ends of the upper streaks 19 are arranged in the rising portion 14 and concrete is cast to construct the first layer 12. After that, the reinforcing bars 18 and the upper bars 19 are arranged, and concrete is cast to construct the second layer 13.

In the bottom slab structure as described above, there is no oblique line at the crossover portion 15, and the cost of the reinforcing bar is reduced. Moreover, according to the construction method as described above, there is no difficult arrangement of the oblique streaks, and the arrangement of the reinforcing bars is easy. Also, the second layer 1
3, the side wall 20 can be constructed in parallel with the construction, and the construction period can be shortened.

[0013]

According to the bottom plate structure of the underground tank according to the first aspect of the present invention, the first layer having the rising portion protruding upward at the peripheral edge, and the first layer is constructed inside the rising portion of the first layer. The upper layer, which is arranged in a substantially horizontal direction on the second layer, is bent so as to descend laterally at a peripheral portion of the second layer, and Since the tip is buried in the rising portion of the first layer, the conventional oblique streaks and the crossover main streaks are not required, and the reinforcing bar cost is reduced.

According to the construction method of the second aspect,
When constructing the first layer having a rising portion on the periphery, the first layer is constructed with the end of the upper streak buried in the rising portion, and then the main bar is buried on the upper surface of the first layer. Since the second layer is constructed by the above, there is no difficult arrangement of the oblique streaks, the arrangement of the reinforcement is easy, and the time required for the arrangement of the reinforcement is reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a bottom plate structure of an underground tank according to the present invention.

FIG. 2 is a side view in which a part of an example of a conventional underground tank is viewed in cross section.

FIG. 3 is a sectional view showing a bottom plate structure of the underground tank shown in FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Bottom plate 12 1st layer 13 2nd layer 14 Erect part 15 Crossing part 19 Upper line

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masanobu Kuroda 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Corporation (72) Inventor Atsushi Sejima 1-2-3 Shibaura, Minato-ku, Tokyo Shimizu (72) Inventor Kiyoshi Asano 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Corporation (72) Inventor Katsuo Maruyama 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Corporation Incorporated (58) Fields surveyed (Int.Cl. ⁷ , DB name) E04H 7/18 303 B65D 88/76 E02D 29/045

Claims (2)

(57) [Claims] A first layer on a lower side and a second layer formed on an upper surface side of the first layer, wherein a side surface of the first layer, an upper surface of a peripheral portion of the first layer, and the second layer are formed. A bottom plate structure of an underground tank in which two side surfaces are constructed as crossover portions, wherein a rising portion protruding upward is formed at a peripheral portion of the first layer, and inside the rising portion of the first layer. The upper layer arranged substantially horizontally in the second layer and the upper layer is bent so as to descend laterally at the periphery of the second layer, and the tip of the upper layer is the first layer. A bottom plate structure for an underground tank, wherein the bottom plate structure is buried in the rising portion of the layer. 2. A construction method for constructing a bottom plate structure of an underground tank according to claim 1, wherein, when constructing a first layer having a rising portion on a peripheral portion, an end of the upper streak is bent downward. And constructing a first layer with the ends arranged in the rising portion, and then constructing a second layer with the upper bar buried on the upper surface of the first layer. An underground tank construction method characterized by the following.