JP2005307691A - Work platform of underground type low temperature tank - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a work platform for efficiently performing construction work and inspection work in a haunch part in an underground type low temperature tank having the haunch part between side wall concrete and base concrete. <P>SOLUTION: Support columns 11 are arranged in the circumferential direction along the haunch part 3, and a lower end part of the support column 11 is fixed to a peripheral fringe part of the base concrete 1. A beam 12 is extended toward an outer side in the radial direction of the tank from an upper part of each support column 11 to cross the haunch part 3, and a tip of the beam 12 is fixed to a lower end part of the side wall concrete 2. An inner side rail 13 is attached to a side face of the support column 11, and an outer side rail 14 is attached to a lower face of the beam 12. The inner side rail 13 and the outer side rail 14 are extended in the circumferential direction along the haunch part 3. A movable scaffold 15 is stretched between the inner side rail 13 and the outer side rail 14. The movable scaffold 15 can move in the circumferential direction along the haunch part 3. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is a work platform used in the construction of an underground storage tank for storing LNG and the like, and particularly in an underground storage tank having a structure having a haunch part between side wall concrete and bottom slab concrete. It relates to a work platform used for interior work.

  In underground storage tanks for storing low-temperature liquefied gases such as LNG and LPG, the inner surface of a concrete housing is provided with a membrane (a pleated corrugation is provided to absorb thermal contraction and thermal expansion associated with fluctuations in liquid level, etc. A structure covered with a thin sheet metal panel) is employed. In such underground storage tanks, in order to prevent excessive stress concentration on the concrete frame due to pumping pressure, the bottom slab concrete that constitutes the bottom surface and the side wall concrete that constitutes the side surface are pin-coupled, and joints are provided It was general. However, such a structure requires a water stop plate to prevent groundwater from entering the joints of the bottom slab concrete and the side wall concrete, and it is necessary to take measures to alleviate the joint steps. There was a problem that the cost increased.

  In contrast, in recent years, as shown in FIGS. 3A and 3B (Patent Document 1), the bottom slab concrete 1 and the side wall concrete are provided by providing a haunch portion 4 at the connecting portion between the bottom slab concrete 1 and the side wall concrete 2. 2 has been proposed. By providing such a haunch portion 3, the rigidity of the connecting portion is increased and the stress concentration is reduced, so that the bottom slab concrete 1 and the side wall concrete 2 can be integrated.

However, since the height of the haunch portion is about 2 m, for example, and the radial width is more than that, the construction work for attaching a member such as a heat insulating material or a membrane to the inside of the haunch portion is not easy. That is, even if it is attempted to lower the working gondola along the side wall from above the storage tank, it is not easy to lower it to the bottom surface because of the haunch portion. Further, even if a walking deck is provided on the membrane 5 on the bottom surface (at that stage, it is assumed that the heat insulating material 4 and the membrane 5 are already attached to the bottom surface and the side surface) Cannot reach the top of the haunch part directly. In such a case, there is also a risk of damaging the already completed bottom membrane.
JP 2003-278999 A

  The present invention has been made in view of the above-described problems in the construction of underground low-temperature storage tanks, and an object of the present invention is to provide a haunch for an underground low-temperature storage tank having a haunch portion between side wall concrete and bottom slab concrete. An object of the present invention is to provide a work platform for efficiently performing construction work and inspection work in a section.

Work base for underground low-temperature storage tank of the present invention,
A work platform used in the construction work of a haunch part in an underground low-temperature storage tank having a haunch part between bottom slab concrete and side wall concrete,
Struts arranged circumferentially along the haunch part and fixed to the peripheral part of the bottom slab concrete,
A beam extending in the lateral direction from the top of each support so as to straddle the haunch part, and a tip fixed to the lower end of the side wall concrete,
An inner rail attached to the side of the column and extending circumferentially along the haunch,
An outer rail attached to the underside of the beam and extending circumferentially along the haunch,
A movable scaffold spanned between the inner rail and the outer rail, guided by the inner rail and the outer rail, and movable in the circumferential direction along the haunch portion;
It is provided with.

  The work platform of the present invention is used in the following manner, for example, in the construction work of the haunch part of the underground low-temperature storage tank. The worker gets on and off the working gondola lowered along the side wall from the walking deck attached on or on the beam. Further, the worker gets down from the walking deck onto the movable scaffold using the walking deck or the stairs attached to the support column. Subsequently, the construction work (for example, attachment of a heat insulating material and a membrane) of the hunch part is performed while the movable scaffold is sequentially moved in the circumferential direction along the hunch part. Here, the movable scaffold has a shape that follows the inclination of the haunch portion, and can be disposed near the haunch portion, so that the worker can efficiently perform the construction work of the haunch portion with a relatively easy posture. be able to.

  In addition, since it is assumed that the inner surface covering member such as a heat insulating material or a membrane is already attached to the bottom surface and the side surface at the stage where the interior work of the haunch portion is performed, the support column is, for example, an inner surface on the bottom slab concrete. It fixes to the fixture which attaches a coating | coated member.

  Similarly, the front-end | tip of the said beam is fixed to the fixing metal fitting for attaching an inner surface covering member on the said side wall concrete, for example.

  According to the work platform of the underground low-temperature storage tank of the present invention, construction work and inspection work in the haunch part can be performed efficiently.

  1 and 2 show an example of a work platform for an underground low-temperature storage tank according to the present invention. 1 is a cross-sectional view taken along a cut surface including the central axis of the storage tank, and FIG. 2 is a plan view when the work platform is viewed from above. In the figure, 11 is a support, 12 is a beam, 13 is an inner rail, 14 is an outer rail, and 15 is a movable scaffold.

  As shown in FIG. 1, this storage tank is provided with a haunch portion 3 between bottom slab concrete 1 and side wall concrete 2. In addition, since the whole structure of a storage tank is the same as that of FIG. 3 shown previously, the description about it is abbreviate | omitted.

  The struts 11 are arranged in the circumferential direction along the haunch portion 3, and the lower end portion of the struts 11 is fixed to a fixture 21 provided at the peripheral edge of the bottom slab concrete 1. In addition, what is used in order to attach the heat insulating material 4 and the membrane 5 on the bottom slab concrete 1 can be utilized for these fixing brackets 21. The beam 12 extends from the upper part of each column 11 to the outside in the radial direction of the storage tank so as to straddle the haunch part 3, and the tip of the beam 12 is fixed to a fixing bracket 22 provided at the lower end of the side wall concrete 2. Has been. In addition, what is used in order to attach the heat insulating material 4 and the membrane 5 on the side wall concrete 2 can also be utilized for these fixing brackets 22. In this example, the beam 12 is once bent upward in the vicinity of the tip (outer peripheral side) and then bent again in the lateral direction to reach the side wall surface.

  An inner rail 13 is attached to the side surface of the support column 11 on the hunch part side. The inner rail 13 extends in the circumferential direction along the haunch portion. An outer rail 14 is attached to the lower surface of the beam 12. The inner rail 14 also extends in the circumferential direction along the haunch portion. A movable scaffold 15 is bridged between the inner rail 13 and the outer rail 14. Specifically, a plurality of wheels 17 are attached to the radially inner end of the movable scaffold 15, and these wheels 17 are supported by the inner rail 13. A plurality of trolleys 18 are attached to the radially outer end of the movable scaffold 15, and these trolleys 18 are suspended from the outer rail 14. Accordingly, the movable scaffold 15 is guided by the inner rail 13 and the outer rail 14 and can move in the circumferential direction along the haunch portion 3.

  The movable scaffold 15 is arranged substantially parallel to the haunch portion 3 so as to face the haunch portion 3 with an appropriate interval. A step board 19 is attached to the movable scaffold 15 in a staircase pattern. On the upper surface of the beam 12, a walking deck 20 is provided. An operator can get down on the walking deck 20 from a working gondola (not shown) lowered along the side wall.

  By using such a movable scaffold 15, it becomes easy for an operator to approach the inclined surface of the haunch part 3, and it is possible to efficiently perform installation work and inspection of a heat insulating material and a membrane in a stable posture. become. In addition, work equipment such as a lever block and a jack can be attached to the movable scaffold 15 and the beam 12 when attaching the heat insulating material and the membrane. Furthermore, by attaching stairs etc. to the support | pillar 11, an operator can also get down to the bottom face of a storage tank from said walk deck 20. FIG.

  In addition, although it is desirable for work efficiency to install the support | pillar 11, the beam 12, the inner rail 13, and the outer rail 14 as described above over the entire circumference in the circumferential direction of the storage tank, It is possible to install it in a part and shift its position sequentially as the construction progresses.

The longitudinal direction sectional view showing an example of the work frame based on the present invention. The top view which shows an example of the work mount based on this invention. It is a figure which shows the outline of the underground type low temperature storage tank which has a haunch part between side wall concrete and bottom slab concrete, Comprising: (a) is a whole structure, (b) is the elements on larger scale of a haunch part.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Bottom slab concrete, 2 ... Side wall concrete, 3 ... Haunch part, 4 ... Heat insulating material, 5 ... Membrane, 11 ... Support | pillar, 12 ... Beam, 13 ... Inner rail, 14 ... outer rail, 15 ... movable scaffold, 17 ... wheel, 18 ... trolley, 19 ... tread, 20 ... walking deck, 21, 22 ... fixed Hardware.

Claims (3)

A work platform used in the construction work of the haunch part in the underground low temperature storage tank having the haunch part between the bottom slab concrete and the side wall concrete,
Struts arranged circumferentially along the haunch part and fixed to the peripheral part of the bottom slab concrete,
A beam extending in the lateral direction from the top of each support so as to straddle the haunch part, and a tip fixed to the lower end of the side wall concrete,
An inner rail attached to the side of the column and extending circumferentially along the haunch,
An outer rail attached to the underside of the beam and extending circumferentially along the haunch,
A movable scaffold spanned between the inner rail and the outer rail, guided by the inner rail and the outer rail, and movable in the circumferential direction along the haunch portion;
Working base for underground low-temperature storage tanks characterized by comprising   2. The work base for an underground low-temperature storage tank according to claim 1, wherein the support column is fixed to a fixing bracket for attaching an inner surface covering member on the bottom slab concrete.   The work stand for the underground low-temperature storage tank according to claim 1, wherein a tip of the beam is fixed to a fixing bracket for attaching an inner surface covering member on the side wall concrete.

Images