JPS5838679B2 - Method for reinforcing spherical tank support members - Google Patents

Description

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

The seismic design standard for spherical tanks conventionally used for storing LPG, etc., is to withstand a horizontal force of 0.22 to 0.3 times the weight of the tank including its contents (generally speaking, This is called the seismic coefficient) The tank support structure was designed.

However, recently, this standard has been deemed insufficient in its seismic strength, and there is an opportunity for a new standard to be established to raise the seismic coefficient to approximately 0.45 to 0.6.

However, apart from the case where a new spherical tank is to be constructed in the future, in order to reinforce the support structure of an existing spherical tank to comply with this new standard, for example, the dimensions of each member in the support structure must be increased by one rank. Possible methods include replacing the tank with a new one, or welding a bracket to the tank body and attaching an oil damper between it and the foundation, but both require a long tank outage period for reinforcement work on the tank body and support members. In order to use fire, the tank must be opened, and since tanks are generally constructed in groups, temporary fire walls must be built to prevent fires from occurring in other tanks in order to carry out construction using fire. However, there were drawbacks such as increased construction costs.

Furthermore, since the oil damper method requires a large foundation, it has the disadvantage of affecting the foundation of existing tanks.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a new method for easily reinforcing existing spherical tank support structures without using fire, by overcoming the difficulties of these conventionally proposed reinforcement methods.

That is, the gist of the present invention is to provide a support structure for an existing spherical tank, which is a support member for the spherical tank; mortar injection holes are drilled at the bottom of each of the steel pipe supports and bracing, and pressure relief holes are drilled at the top. After setting the pipe and filling the pipe struts and bracing with mortar through the lower mortar injection hole, close the upper pressure relief hole, and then press-fit mortar through the lower mortar injection hole. The present invention provides a method for reinforcing a spherical tank support member, which comprises closing the lower mortar injection hole and solidifying the mortar press-fitted therein.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

The figure is an explanatory diagram showing one embodiment of the present invention.

The lower part of the spherical tank 1 is supported by a number of columns 3, 3, . . . fixed on the foundation 2.

This support is attached from the pipe to the bottom of the spherical tank, for example.
Six pieces are evenly spaced.

Between the pillars 3, 3, diagonal reinforcing members 4, 4, 4, .

In many cases, pipes are used for the supports and bracing of spherical tanks.

Such support members are reinforced in accordance with the present invention by filling the pipe supports or bracing with a compression resistant material such as mortar or concrete.

That is, holes 5 with a diameter of about 1 inch are drilled in the upper and lower parts of the steel pipe bracing 4 using a non-spark drill or the like.
6 is opened, mortar or concrete mixed in an external mixer truck 8 is injected by a pump 9 through a conduit 10 through an injection valve 11 provided in the lower hole 6, the pressure is removed from the upper hole 5, and finally the upper A vent valve 12 provided in the hole is closed, and mortar or concrete is press-fitted through an injection valve 11 provided in the lower hole 6 to completely and densely inject the mortar or concrete.

Note that a pressure relief hole 7 and a vent valve 13 may be provided in the middle of the bracing 4 as necessary to adjust the filling pressure of mortar or concrete.

In this way, by press-fitting and solidifying mortar into the existing pipe bracing, it is possible to create a bracing with an internal mortar core that is particularly resistant to compression and an external steel pipe jacket that is particularly resistant to tension. It can be easily implemented without using it.

The method of reinforcing the bracing 4 described above can be similarly applied to the support column 3.

That is, an injection valve 14 is provided at the bottom of the pillar 3, and a vent valve 15 is provided at the top, and mortar or concrete is similarly injected.

Note that reinforcing bars such as wire may be inserted into the steel pipe as necessary.

When an increase in the seismic coefficient is required in the design of a spherical tank support structure, conventional bracing is weak against compression and may cause buckling, leading to the risk of the support structure being destroyed; however, with the reinforcing method of the present invention, Reinforced with compression-resistant mortar or concrete, this highly effective reinforcement can be easily applied to existing spherical tank support members without the use of fire to meet the demands of increased seismic coefficients. .

The injection material can be either mortar or concrete.

[Brief explanation of the drawing]

The drawings are explanatory diagrams showing one embodiment of the present invention. 1... Spherical tank, 2... Foundation, 3.
...Strut, 4...Bracing, 5...
... Bracing upper hole, 6 ... Bracing lower hole, 7 ... Bracing pressure elimination hole, 8 ... Mixer truck, 9 ... ··pump,
10... Conduit, ICl3... Injection valve, 12°13.15... Vent valve.

Claims (1)

[Claims] 1. In the existing spherical tank support structure, a mortar injection hole and a pressure relief hole are drilled in the upper part of each of the steel pipe supports and bracing that are the supporting members of the spherical tank, and the lower mortar After filling the pipe support and bracing with mortar through the injection hole, close the upper pressure relief hole, and press mortar through the lower mortar injection hole. A method for reinforcing a spherical tank support member, comprising closing the tank and solidifying the mortar press-fitted inside.