JPH0115669B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a method for jacking up a cylindrical tank when repairing its foundation, replacing its bottom wall, or the like.

Regarding the foundation on which the tank is installed, if uneven settlement occurs, it can cause cracks in the tank and disaster, so it is necessary to correct the foundation evenly as soon as it is discovered.
Additionally, in order to prevent corrosion of the bottom wall of the tank, it may be necessary to modify the foundation by partially changing the material. On the other hand, the bottom wall of the tank often needs to be replaced due to corrosion caused by internal factors such as the liquid stored in the tank or external factors such as rainwater infiltrating between the tank and the tank foundation.

When modifying the foundation or replacing the bottom wall, it is necessary to temporarily lift the tank, and the jacking method using jacks is generally used as the lifting method. This jacking method involves fixing multiple jack brackets to the outer peripheral surface of the lower end of the tank side wall, and then temporarily lifting the tank using jacks inserted between the jack brackets and the tank foundation. It's a method.

Incidentally, the side walls of a tank are generally designed to have a wall thickness that is sufficient to withstand the internal pressure caused by the liquid stored in the tank, so they are extremely thin and extremely vulnerable to large external forces. Therefore, when jacking up a tank, the horizontal component force due to the moment due to the tank load supported by the jack bracket is
Since the burden is borne by the side wall, it is necessary to reinforce the side wall to prevent deformation and buckling of the side wall.

Therefore, in conventional tank jacking methods, measures have been taken to reinforce the side walls of the tank, as shown in FIG. 1 or 2.

That is, in the example shown in FIG. 1, a reinforcing ring 2 is fixed to the upper end of the tank side wall 1, and a plurality of jack brackets 3 are fixed to the reinforcing ring 2 and the outer peripheral surface of the lower end of the side wall 1. After fixing reinforcing plates 4 between the two, the tank was jacked up. However, in this method, since the reinforcing ring 2 and the reinforcing plate 4 are large, the cost of materials, bending, etc. are large, and the fixing work such as welding is required at a high place. Problems were pointed out in terms of cost, efficiency, and safety, such as the need for heavy equipment and scaffolding for the work, and the need for fire prevention measures at high places, making the work dangerous.

Next, in the example shown in FIG. 2, after installing the reinforcing material 6 between the lower end of the side wall 1 and the bottom wall 5,
The tank is jacked up, and the horizontal component force generated due to the tank load supported by the jack bracket 3 is borne by the bottom wall 5 via the reinforcing member 6. However, in this method, when the tank is jacked up, the side wall 1 and the bottom wall 5 are
A large tensile stress is generated in the fillet weld 7 of the tank, which poses a safety problem for the tank.Furthermore, it may be possible to jack up the tank and repair the foundation, but the bottom wall 5 must be replaced. It was also pointed out that this method is not possible.

In view of the above circumstances, the present invention has been made to solve the problems of the conventional examples described above, and is to provide a structure in which the lower end of the inside of the tank side wall is constructed from struts installed radially on the same plane. Cost and efficiency can be reduced by reinforcing the tip of the beam that corresponds to the jack bracket by fixing it to the backing mounting material on the inner circumferential surface of the tank side wall under a retaining rib, and then lifting the tank. , which is excellent in terms of safety, and on the other hand, by adding a step of suspending and holding the bottom wall of the tank using the beam via a reinforcing member, and then lifting the tank, the load when jacking up is transferred to the side wall and bottom wall of the tank. The purpose of the present invention is to propose a method for jacking up tanks that can be processed without any burden.

Embodiments of the present invention will be described below with reference to FIG. 3 and the subsequent drawings.

First, the tank is composed of a cylindrical side wall 11, a top wall 12 and a bottom wall 13 fixed to the upper and lower end surfaces of the side wall 11, and is installed on a foundation 14.

When jacking up the tank, first, a plurality of jack brackets 15 are fixed to the outer peripheral surface of the lower end of the side wall 11 at equal intervals.

On the other hand, the lower end of the inside of this side wall 11 is reinforced by a plurality of beams 16 installed radially on the same plane.

Examples of reinforcement by the beam 16 shown in FIGS. 3 and 4 will be described next.

Mounting materials 17 are fixed to the inner circumferential surface of the lower end of the tank side wall 11 corresponding to the fixed locations of the jack brackets 15, and the mounting materials 17 are attached to the beams 16.
One end is fixed. Reference numeral 18 denotes a column fixedly provided between the top wall 12 and the bottom wall 13 at the center of the tank, and the other end of each beam 16 is fixed to the column 18 via a ring 19 so that each beam 16 is installed radially on the same plane. ing. It is better that the number of beams 16 is as large as possible, and it is also preferable that the beams 16 are arranged so as to face each other with the supports 18 interposed therebetween. In order to securely hold this beam 16, ribs 20 are provided between the beam 16 and the mounting material 17, one each on the top and bottom, and a bar 21 is provided between the ring 19 fixed to the support 18 and the lower end of the mounting material 17. It is located between the department. Furthermore, in order to prevent the struts 18 and beams 16 from hanging down at the center of the tank, the top wall 12 is partially opened and a hanging fitting 22 is attached.
A rope 24 such as a wire is stretched between the two hanging fittings 22 and 23 via a turnbuckle 25.

Another example of reinforcement by beams 16 is shown in FIG. This is an example of reinforcing a tank that does not have a support column 18, unlike the example described above. In this example, the other end of the beam 16 is fixed to a ring 19 so as to be installed radially on the same plane, and this ring 19 has one upper and lower end between the upper end and the lower end of the mounting member 17. It is held and prevented from hanging down by the bars 21 arranged in parallel. Since the other members are substantially the same as those in the example shown in FIG. 3, explanations of the reference numerals will be omitted.

After the beams 16 have been reinforced as described above, the tank is lifted by operating the jacks 26 inserted between each jack bracket 15 and the tank foundation 14.

While the tank is being raised to the desired height, the tank foundation 14 is modified and the bottom wall 13 of the tank is replaced (the old bottom wall 13 is removed, the new bottom wall 1
3) and other work is performed. FIG. 6 shows the state in which the old bottom wall 13 has been removed.

While the tank is being lifted in this manner, the tank load is supported by the jack bracket 15, and the horizontal component force generated in conjunction with this support load is directly borne by the beam 16.

After the above operations are completed, the tank is lowered onto the foundation 14 by operating the jack 26.

The method for jacking up a tank according to the present invention includes:
This is performed by the steps described above.

In addition to the step of reinforcing the lower end of the tank side wall 11 with the beam 16 described above, the tank bottom wall 13 is suspended and held by the beam 16, and then the tank is lifted up with the jack 26 described above. The jack up method is explained as follows.

That is, the lower end of the side wall 11 is reinforced by each beam 16, and reinforcing members 27 are radially fixed to the tank bottom wall 13 directly below each beam 16, as shown in FIG. 7, for example. Each reinforcing member 27 and the corresponding beam 16 are suspended and held by a rope 28 such as a wire, and furthermore, in order to reinforce this suspension, the support 18 and the bottom wall 13 are connected by a stopper 29. I'll keep it.

After that, the process proceeds to the step of lifting the tank using the jack 26.

According to this method of jacking up a tank, while the tank is being lifted, the tank bottom wall 13 can be kept flat and horizontal without sagging at all times; Although limited to modification, rope 2
By releasing the hanging hold of the bottom wall 13 by the stopper 8 and the stopper 29, the bottom wall 13 can be easily replaced.

As explained above, the method for jacking up a tank according to the present invention involves reinforcing the lower end of the inside of the tank side wall with beams installed radially on the same plane, and then lifting the tank.
The tank can be lifted safely without the risk of side wall deformation or buckling, and work such as foundation modification and bottom wall replacement can be carried out safely, and the tank can also be reused after the fact without any problems. . Furthermore, since the reinforcement of the side walls does not require work at high places compared to conventional methods, it has excellent effects in terms of cost, efficiency, and safety.In addition, both foundation correction and bottom wall replacement work can be easily performed. This method has been implemented, and its effects are remarkable, such as solving all the problems of this type of conventional jack-up method at once.

In addition to the above-mentioned effects, the tank jack-up method includes a step of suspending and holding the bottom wall with a beam via a reinforcing member, and then lifting the tank.In addition to the above-mentioned effects, even if the tank is lifted, the bottom wall remains intact. It is always held flat and horizontal without bending, making it suitable for inspections, etc.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 are longitudinal sectional views of a tank, each showing the initial state of the process in a conventional tank jacking method. 3 to 7 are explanatory diagrams of an embodiment of the method for jacking up a tank according to the present invention. Figure 3 shows the situation at the beginning of the process, and is a longitudinal sectional view of the tank, Figure 4 is a horizontal sectional view, and Figure 5 shows another example of the initial stage of the process, which is a longitudinal sectional view of the tank. be. FIG. 6 shows the final state of the process in the example shown in FIGS. 3 and 4, and is a longitudinal sectional view of the tank. FIG. 7 is an enlarged vertical sectional view of the main part of the tank, showing the final state of the jack up method which includes the step of suspending and holding the bottom wall. 11...Side wall, 12...Top wall, 13...Bottom wall,
14... Basics, 15... Jacket bracket, 1
6...beam, 17...mounting material, 18...post, 19
...Ring, 20...Rib, 21...Bar, 22
... Hanging metal fitting, 23 ... Hanging metal fitting, 24 ... Rope, 25 ... Turnbuckle, 26 ... Jacket, 27 ... Reinforcement member, 28 ... Rope, 29 ...
…Fasteners.

Claims (1)

[Scope of Claims] 1. A plurality of jack brackets are fixed to the outer peripheral surface of the lower end of the tank side wall, and the lower end of the inside of the tank side wall is radially installed in the air at a predetermined distance above the bottom wall on the same plane. Reinforce the tip of the beam made of the tension material by fixing it to the inner circumferential surface of the tank side wall to the mounting material of the backing with a retaining rib in correspondence with the jack bracket, and then attach the above-mentioned jack A method for jacking up a tank, characterized in that the tank is lifted by a jack inserted between a jacking bracket and a tank foundation. 2. A plurality of jack brackets are fixed to the outer circumferential surface of the lower end of the tank side wall, and the lower end of the inside of the tank side wall is connected to a strut member radially installed in the air at a predetermined distance above the bottom wall on the same plane. This beam is reinforced by fixing the end of the beam to the inner peripheral surface of the tank side wall in correspondence with the jack bracket to the mounting material of the backing under the attachment ribs, and this beam also strengthens the bottom wall of the tank. A method for jacking up a tank, characterized in that the tank is suspended and held through the jack bracket and then lifted by a jack inserted between the jack bracket and the tank foundation.