JPS6032080B2 - Reinforcement method for spherical tank support structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for reinforcing the support structure of a spherical tank used for storing, for example, liquefied petroleum gas (LPG).

In recent years, with the development of industry, hazardous materials handling facilities, storage tanks, etc. have become densely packed in cities and industrial areas, and once these facilities are destroyed by an earthquake, etc., the impact of such a disaster is immeasurable. be.

For this reason, the issue of the seismic strength of high-pressure gas production facilities has been taken up in recent years in our country, and seismic design standards for high-pressure gas production facilities have already been imposed in some regions, and existing facilities are also required to improve where their strength is lacking. It is mandatory.
In other words, the seismic design of LPG spherical tanks has conventionally been designed using the static design seismic intensity specified in the Construction Standards Act, and the horizontal seismic intensity that is applied to the structure during an earthquake is calculated by considering a certain seismic intensity for the total weight including the contents. This design seismic intensity is 0.23.
~0.3 tank support structures have been designed.

However, under the new standard, the design seismic intensity is determined by dynamic analysis that takes into account the vibration characteristics of the structure, and as a result, the design seismic intensity is 0.
．． It was raised to 45-0.6. In order to strengthen the support structure of an existing spherical tank to comply with this new standard, for example, it is possible to replace the support structure's support structure with one that is one rank larger in size, or by welding a placket to the tank body. Install an oil damper between the foundation and the tank to increase its damping effect and reduce the horizontal seismic intensity of the tank, or install a certain pendulum on the support structure to lengthen the natural period of the structure and reduce earthquake input. Possible methods include control methods.

However, all of these reinforcement methods use fire, requiring the tank to be opened, requiring long periods of tank downtime for construction work, and requiring large amounts of investment.

Furthermore, holes are drilled in the steel pipe struts and steel pipe placings that are supporting members of the tank, and mortar is injected and solidified without using fire to increase and strengthen the buckling strength of the struts and the placings. Although some methods have been used and have had some effect, they are still not sufficient. The present invention overcomes the difficulties of these conventionally proposed reinforcement methods and provides a method for easily reinforcing the support structure of a spherical tank in a very short period of time without using fire or requiring a large amount of investment. It is.

In other words, the gist of the present invention is to fix a band with a flange made of a steel plate to each of the upper and lower parts of a steel pipe strut, which is a support member of a spherical tank, using an adhesive for bonding metal, and to attach a band with a flange made of a steel plate to the flange of the band. This method involves installing tie rods diagonally between the struts through pre-prepared holes to provide additional bracing to reinforce the tank support structure. Further, to explain with reference to the embodiment shown in the attached drawings, the lower part of the spherical tank 1 is supported by a number of steel pipe supports 3 fixed on the foundation 2, and between the supports there are steel tie rods (or steel pipes). Racing (wealth.

It is fixed and reinforced by material) 4. The supports for reinforcing these tank support structures by the method of the present invention are made by attaching bands 5, 5' with split snaps made of, for example, steel plates to the upper and lower parts of each strut, and attaching the bands 5, 5' to the collars 9, 9' of the bands in advance. A vertical reinforcing tie rod placing 6 is constructed by inserting a steel rod diagonally between the adjacent columns through the provided holes 10, 10' and using bolts 8'. In order to fix the band to the support, an adhesive for bonding metal, such as epoxy resin adhesive 7, is filled between the band and the support, and the two bands 5 and 5' are combined into one body using bolts 8. Tighten and secure. Note that the flange band attached to the support column is not limited to the two-split flange band described above, and may be of any shape as long as it has a hole for installing a bolt attachment and a tie rod.

In addition, wrapping reinforced concrete around the band installation part of the support can improve fire resistance and prevent buckling of the support pillar and damage to the anchor bolt.

The method of the present invention is an effective method for reinforcing a spherical tank support structure that increases the seismic strength of the tank without performing any mechanical work that would reduce the strength of the pillars that support the tank. This method can be implemented in a short period of time and with a small investment, without using fire at the site, and the practical effects are extremely large.

[Brief explanation of drawings]

Fig. 1 is an overall view of a spherical tank support structure showing an embodiment of the present invention, Fig. 2 is a partially exploded explanatory view of the mounting portion of reinforcing fittings, Fig. 3 is a partial horizontal sectional view taken from “A-A”,
FIG. 4 is an exploded explanatory diagram of the main parts of FIG. 2. 1... Spherical tank body, 2... Foundation,
3... Pillar, 4... Existing tie rod, 5,5'
...Band, 6...Additional tie rod, 7...
...Adhesive, 8...Band vertical bolt, 8'
...Additional tie rod tightening bolt, 9,9'...
・Band brim, 10, 10'...Perforation. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1 A band with a flange made of a steel plate is fixed to the upper and lower parts of the support structure of a spherical tank consisting of multiple columns and bracing using a metal bonding adhesive, and a perforation is made in advance in the part of the flange. A method of reinforcing a spherical tank support structure in which tie rods are installed diagonally between the struts to provide additional bracing.