JP2019138065A - Construction method of flat bottom cylindrical tank provided with concrete walls - Google Patents

Abstract

PROBLEM TO BE SOLVED: To construct a flat-bottomed cylindrical tank made of metal provided with a concrete outer tank for the purpose of tsunami countermeasures, etc. Provides a construction method for formwork tanks. SOLUTION: After temporarily installing a plurality of formwork elevating means 11 for suspending an outer formwork 3b1 on a pedestal 12 temporarily provided at the top or a vicinity of the top of an inner tank side plate 4b, water is poured into the inner tank 4 and a floating roof is provided. 6 is raised to the concrete placing height for constructing the outer tank side wall 3b, and the outer formwork 3b1 is raised to a height facing the floating roof 6 in conjunction with the raising of the floating roof 6 by the plurality of formwork elevating means 11. The step of raising the inner tank side plate 4b and the step of placing concrete between the inner tank side plate 4b and the outer formwork 3b1 while reinforcing the inner tank side plate 4b with the floating roof 6 and the pressure bag 6a are sequentially repeated a plurality of times. .. [Selection diagram] Fig. 1

Description

  The present invention relates to a construction method of a flat bottom cylindrical tank provided with a concrete outer tub for storing a liquid such as heavy oil.

A steel flat bottom cylindrical tank that stores heavy oil etc. was swept away by the tsunami generated by a major earthquake, and the tank storage liquid spilled into the city area, spreading the fire and making tsunami damage serious. There is a need for a tank that is not easily washed away.
Generally, a flat bottom cylindrical tank for storing petroleum is composed of a steel bottom plate and side plates, and is often placed on a foundation without being anchored with anchor bolts or the like. When there are few, it is easy to be swept away by the pressure and buoyancy of the tsunami.

As an example of the technology for preventing the tank from flowing out, there is an invention of “Structure against earthquake / tsunami” of Patent Document 1. In this invention, a plurality of sheet piles and steel pipe sheet piles are placed on the ground around the tank to prevent collisions of structures with other structures due to earthquakes and tsunamis, collisions of drifting objects with structures, etc. An earthquake / tsunami countermeasure structure for a structure that can be used is disclosed.

Further, the invention of a tank having a concrete side wall which is heavier than a steel tank and has a side wall capable of receiving a side pressure caused by a tsunami has been made. There is an invention of "construction method". In this invention, a tank inner tank is constructed, the inner tank is used as an inner mold for placing concrete, and water is poured into the inner tank to float the floating roof installed in the inner tank. This is a method of placing concrete in a state where the inner tank side plate is reinforced from the inner surface by pressurizing with a fluid injected into a pressure bag attached annularly along the outer periphery of the floating roof, up to the design height A construction method for a floating roof type flat bottom cylindrical tank having a concrete wall in which an outer formwork and a floating roof are sequentially raised and a concrete side wall as an outer tub is constructed from below to above is disclosed.

Furthermore, in the “construction method of a composite structure storage tank” of Patent Document 3, after constructing a steel tank, an outer formwork for placing concrete is suspended from a temporary beam provided at the top of the steel tank, While sealing the steel tank and applying internal pressure, the outer mold is moved upward and downward sequentially from the bottom of the tank, and concrete is sequentially applied to the outer wall of the steel tank from below the tank using the outer mold. A method for constructing a composite structure storage tank is disclosed.

Furthermore, the invention of “Slip Form Device and Cylindrical Wall Body Construction Method” of Patent Document 4 includes a yoke provided with an outer formwork panel facing the outer peripheral surface of a cylindrical material lining the inner peripheral surface of the cylindrical wall body. A slip-form apparatus having only an outer mold frame engaged with the horizontal movement restriction member installed on the cylindrical member so as to be movable up and down while restricting movement in the horizontal direction, and a method for constructing the cylindrical wall body are disclosed. Yes.

JP 2008-231768 A Japanese Patent Application No. 2017-231290 Japanese Patent Publication No. 63-61462 Japanese Patent Laid-Open No. 2006-138368

The tsunami countermeasures that install piles and sheet piles to prevent outflow around the tank as in Patent Document 1 cannot avoid tsunami pressure and buoyancy acting on the tank, and collision of wood from the building that has flowed out, not necessarily Damage to the tank body cannot be avoided.
In addition, it is not easy to place a large number of piles in the yard of an existing tank in which various pipes are laid vertically and horizontally.
Furthermore, the conventional method of constructing a concrete tank with a metal lining can counteract the side pressure and buoyancy caused by the tsunami, but it is possible when installing a new tank. It cannot be applied to existing tanks that require
Therefore, a structure is adopted in which a concrete side wall is arranged so as to be in contact with the metal tank, and a concrete outer tub is constructed by using the metal tank as an inner formwork when constructing the concrete side wall. This method can be applied to either existing or newly installed flat bottom cylindrical tanks, and is therefore the most reasonable as a countermeasure against tsunami in dangerous goods storage tanks.
As such a flat bottom cylindrical tank having a concrete wall for tsunami countermeasures, it is made of concrete having a design height Hc that can surround the whole or most of the side plate 4b on the outer periphery of a metal tank 1 as shown in FIG. A flat-bottom cylindrical tank 1 having a double shell structure in which the side wall 3b is constructed can be considered.

By the way, since the flat bottom cylindrical tank has been designed to determine the required plate thickness of the side plate based on the internal pressure of the stored liquid, when the steel tank is used as a formwork for the construction of a concrete side wall, It is necessary to consider the deformation of the steel tank side plate due to the external pressure when placing concrete.
Furthermore, in order to shorten the concrete side wall construction process, it is necessary to make the concrete placement height as high as possible, but it is necessary to consider the influence of the deformation of the steel tank described above. The concrete placement height is limited by the strength of the formwork.
In order to suppress deformation due to external pressure during concrete placement when using the steel tank itself as an inner formwork to surround with a concrete wall as a tsunami countermeasure for existing steel tanks, the side plate thickness of the steel tank However, the tank construction cost increases. Further, increasing the thickness of the side plate of the tank is not practical because it will be a modification comparable to the new tank.

The existing slip-form method using the existing or new steel tank as the inner formwork is
It is possible to raise only the outer formwork and install a temporary reinforcement structure on the tank to construct a concrete side wall with the designed height, but this method has the same height as the tank. There were various problems in terms of cost, such as the need to provide a plurality of reinforcing members at circumferential intervals.

Patent document 1 “Structure against earthquake and tsunami countermeasures” is a structure in which a plurality of sheet piles and steel pipe sheet piles are placed on the ground around the tank to prevent movement of the tank and collision of drifting objects with the tank. However, this is not a structure that avoids the side pressure and buoyancy itself of the tsunami acting on the tank, nor is it related to a structure that prevents deformation of the tank side plate.

  The invention of Patent Document 2 “Construction Method of Tank with Concrete Wall” is that when constructing a concrete outer tub, the outer formwork is sequentially raised to the concrete placement height, and water is poured into the tank inner tub. It is a method of raising the floating roof, injecting fluid into the pressurized bag and placing concrete, but in conjunction with the floating roof where the outer formwork located on the outer periphery of the inner tank floated in the inner tank It does not relate to the form slide method of raising and lowering.

Patent Document 3 discloses a method for constructing a composite structure storage tank in which a steel tank is constructed, and then an outer formwork for concrete placement is suspended from a temporary beam provided at the top of the steel tank. Is a method of constructing a composite structure storage tank in which concrete is placed by moving the outer mold frame upward and downward sequentially from the bottom of the tank while applying air pressure, and the steel tank as the inner mold Although it is a construction method in which concrete is cast, it does not relate to a construction method in which a floating roof having a pressure bag is installed in a steel tank and the floating roof and the outer formwork are interlocked to move up and down.
Further, the present invention is a construction method in which the entire inside of the steel tank is sealed, and an internal pressure is applied to the inside of the tank by an air compressor or the like to counter the pouring pressure of the ready-mixed concrete, and the floating roof installed in the inner tank And it is not a construction method that works against the pouring pressure of concrete with a pressure bag.

The invention of Patent Document 4 “Slip Form Device and Cylindrical Wall Construction Method” is a method of using an inner tubular material as an inner mold at the time of placing concrete, and a concrete casting having only an outer mold However, it does not relate to a method of installing a floating roof in the tubular member and moving the floating roof and the outer formwork up and down.
The present invention also relates to a construction method in which concrete is lined with a tubular material, and concrete is newly placed between the tubular material and the outer formwork, and the concrete is brought into contact with an existing steel tank. It does not relate to the method of building the side walls.

The present invention has been made in view of the above-described problems of the prior art, and its object is to construct a metal flat bottom cylindrical tank with a concrete outer tub for the purpose of measures against tsunami and the like In doing so, a flat bottom cylindrical tank side plate, which is an existing or new metal inner tank, is used as an inner mold for constructing a concrete outer tank side wall, and has an annular pressure bag installed inside the metal inner tank. A flat bottom cylindrical shape by a form slide method for constructing the concrete outer tank side wall from the lower side to the upper side by moving the floating roof and the outer mold frame temporarily installed on the outer peripheral part of the metal inner tank in conjunction with each other. The purpose is to provide a tank construction method.

According to a first aspect of the present invention, a form slide method for constructing a tank having a concrete wall is a flat bottom cylindrical tank having a concrete outer tub disposed around a metal inner tub. In construction, the inner tub is a newly constructed metal flat bottom cylindrical tank or an existing metal flat bottom cylindrical tank, and the side plate of the metal inner tub is a side wall of the concrete outer tub. As an inner mold for placing concrete in construction, an outer mold for placing concrete used for constructing the outer tank side wall is temporarily installed on the outer periphery of the cylindrical inner mold, and the outer mold is A mold slide construction method for constructing a concrete side wall provided with a mold lifting means that moves up and down in conjunction with the lifting and lowering of a metal floating roof installed in the inner tank,
After temporarily installing a plurality of mold lifting means for suspending the outer mold on a tent that is temporarily installed near or at the top of the inner tank side plate, water is poured into the inner tank, and the floating roof is connected to the outer tank side wall. Elevating to the concrete placement height for construction and raising the outer formwork to a height facing the floating roof in conjunction with the rising of the floating roof by the plurality of formwork raising and lowering means; While reinforcing the tank side plate with the floating roof and the pressure bag, the step of placing and solidifying the concrete between the inner tank side plate and the outer mold is sequentially repeated a plurality of times, the height of the designed A concrete outer tub side wall is constructed from below to above.

The mold lifting / lowering means used in the mold slide construction method for constructing a tank having a concrete wall according to the invention of claim 2 comprises: a wire having one end fixed to the outer mold; Elevating drive device equipped with an electric winder that enables lowering, a floating roof height measuring instrument for measuring the floating height of the floating roof that floats by pouring water into the metal inner tank, A control device for the lift driving device that receives an electrical signal related to the height position information of the floating roof measured by a floating roof height measuring instrument and can control the lift height of the outer formwork In addition, it is a formwork raising / lowering means capable of winding up or down the outer formwork connected to the electric winder by the wire in conjunction with the floating of the floating roof.

The floating roof height measuring instrument used in the form slide construction method for constructing a tank having a concrete wall according to the invention of claim 3 has one end fixed to the upper part of the floating roof and the other end tensioned. A wire rod coupled to a tensioning device that keeps constant, and an electric winder controlled to keep the tension generated in the wire rod substantially constant so that the wire rod does not loosen as the floating roof moves up and down And measuring the floating height position of the floating roof by measuring the winding length of the wire electrically or optically, or the existing flat bottom It is a floating roof height measuring instrument using an existing liquid level gauge provided in a cylindrical tank, and is used for raising and lowering the outer formwork with an electrical signal related to the measured height position information of the floating roof. It transmits to the control apparatus of a raising / lowering drive apparatus, It is characterized by the above-mentioned.

The floating roof used in the form slide construction method for constructing the tank having the concrete wall according to the invention of claim 4 is a single continuous ring or a plurality of connecting / disconnecting rings continuously along the outer periphery of the floating roof. A pressure bag attached freely, the pressure bag including a fluid inlet for injecting the fluid into the pressure bag or discharging the fluid from the pressure bag; A pressure bag connected to the fluid inlet through a pipe and detachably connected to a pressure device having a pressure control device for controlling the internal pressure in the pressure bag by taking in and out the fluid; A concrete that is placed at a time in the step of placing and solidifying the concrete between the inner tank side plate and the outer mold while reinforcing the inner tank side plate according to claim 1 with the floating roof and the pressure bag. Counters the height pressure The pressure is adjusted by injecting fluid into the pressurized bag according to the concrete placement height so that the pressurized bag is in close contact with the inner surface of the side plate and the side of the floating roof. The inner tank side plate is pressurized and reinforced from the inner surface side, and after the concrete on the outer tank side walls has solidified, the floating roof is freely raised and lowered for the next step. The pressure is controlled by discharging the fluid from the pressure bag and reducing the pressure in the pressure bag.

According to a first aspect of the present invention, a form slide method for constructing a tank having a concrete wall is a flat bottom cylindrical tank having a concrete outer tub disposed around a metal inner tub. In construction, the inner tub is a newly constructed metal flat bottom cylindrical tank or an existing metal flat bottom cylindrical tank, and the side plate of the metal inner tub is a side wall of the concrete outer tub. As an inner mold for placing concrete in construction, an outer mold for placing concrete used for constructing the outer tank side wall is temporarily installed on the outer periphery of the cylindrical inner mold, and the outer mold is A mold slide construction method for constructing a concrete side wall provided with a mold lifting means that moves up and down in conjunction with the lifting and lowering of a metal floating roof installed in the inner tank,
After temporarily installing a plurality of mold lifting means for suspending the outer mold on a tent that is temporarily installed near or at the top of the inner tank side plate, water is poured into the inner tank, and the floating roof is connected to the outer tank side wall. Elevating to the concrete placement height for construction and raising the outer formwork to a height facing the floating roof in conjunction with the rising of the floating roof by the plurality of formwork raising and lowering means; While reinforcing the tank side plate with the floating roof and the pressure bag, the step of placing and solidifying the concrete between the inner tank side plate and the outer mold is sequentially repeated a plurality of times, the height of the designed Since the concrete outer tank side wall is constructed from the bottom to the top,
The floating roof and the outer formwork can be moved up and down several times to the appropriate concrete placement center height, and the concrete outer wall of the design height can be efficiently constructed.
Since the side plate of a new or existing flat bottom cylindrical tank is used as the inner formwork, it is not necessary to temporarily install / remove the inner formwork for placing the concrete side wall, thereby shortening the construction period and reducing the construction cost. .

The mold lifting / lowering means used in the mold slide construction method for constructing a tank having a concrete wall according to the invention of claim 2 comprises: a wire having one end fixed to the outer mold; Elevating drive device equipped with an electric winder that enables lowering, a floating roof height measuring instrument for measuring the floating height of the floating roof that floats by pouring water into the metal inner tank, A control device for the lift driving device that receives an electrical signal related to the height position information of the floating roof measured by a floating roof height measuring instrument and can control the lift height of the outer formwork In conjunction with the floating of the floating roof, because it is a mold lifting means capable of winding or unwinding the outer mold frame connected to the electric winder with the wire,
Since it becomes easy to raise and lower the outer mold corresponding to the rising height of the floating roof, and the outer mold and the floating roof can be easily positioned at the same height, It becomes possible to place concrete in a state in which the concrete is properly reinforced, and the construction period can be shortened.

The floating roof height measuring instrument used in the form slide construction method for constructing a tank having a concrete wall according to the invention of claim 3 has one end fixed to the upper part of the floating roof and the other end tensioned. A wire rod coupled to a tensioning device that keeps constant, and an electric winder controlled to keep the tension generated in the wire rod substantially constant so that the wire rod does not loosen as the floating roof moves up and down And measuring the floating height position of the floating roof by measuring the winding length of the wire electrically or optically, or the existing flat bottom It is a floating roof height measuring instrument using an existing liquid level gauge provided in a cylindrical tank, and is used for raising and lowering the outer formwork with an electrical signal related to the measured height position information of the floating roof. Since it is transmitted to the control device of the lift drive device,
Measures the floating height of the floating roof according to the level of water injected into the inner tank measured by the liquid level gauge installed in the existing floating roof type tank or the winding amount of the wire fixed to the floating roof Based on the result, it becomes easy to adjust the height of the outer formwork, and the outer formwork and the floating roof can be easily positioned at the same height so as to face each other. It becomes possible to place concrete in a state in which the concrete is properly reinforced, and the construction period can be shortened.

The floating roof used in the form slide construction method for constructing the tank having the concrete wall according to the invention of claim 4 is a single continuous ring or a plurality of connecting / disconnecting rings continuously along the outer periphery of the floating roof. A pressure bag attached freely, the pressure bag including a fluid inlet for injecting the fluid into the pressure bag or discharging the fluid from the pressure bag; A pressure bag connected to the fluid inlet through a pipe and detachably connected to a pressure device having a pressure control device for controlling the internal pressure in the pressure bag by taking in and out the fluid; A concrete that is placed at a time in the step of placing and solidifying the concrete between the inner tank side plate and the outer mold while reinforcing the inner tank side plate according to claim 1 with the floating roof and the pressure bag. Counters the height pressure The pressure is adjusted by injecting fluid into the pressurized bag according to the concrete placement height so that the pressurized bag is in close contact with the inner surface of the side plate and the side of the floating roof. The inner tank side plate is pressurized and reinforced from the inner surface side, and after the concrete on the outer tank side walls has solidified, the floating roof is freely raised and lowered for the next step. Since the fluid is discharged from the pressure bag and the pressure in the pressure bag is reduced to control the pressure,
By repeating the pressure reinforcement of the inner tank side plate and concrete placement, the vertical design of the inner tank side plate is maintained without deforming the inner tank side plate due to the concrete placement pressure of the outer tank. It is possible to construct a concrete outer tank side wall having a large height.
Since the floating roof of the tank can be used as a reinforcement structure when placing concrete, there is no need to prepare a separate reinforcement for placing concrete, compared to the case where reinforcement is attached to the entire side plate. As a result, the workability and economy are improved, and the safety of the concrete placement work during the construction of the outer tank side wall is also improved.

It is a whole side explanatory view of the example of the form slide construction method for construction of the tank provided with the concrete wall concerning the present invention. It is a whole side explanatory view of other examples of a form slide construction method for construction of a tank provided with a concrete wall concerning the present invention. It is a flowchart for demonstrating the outline of the process from the tank 1 construction start of the mold slide construction method for construction of the tank provided with the concrete wall to completion of installation of the mold raising / lowering device 11. It is a flowchart for demonstrating the outline of the process from the construction start to the completion | finish of the concrete outer tank side wall 3b of the mold slide construction method for construction of the tank provided with the concrete wall. It is an enlarged view of the A section of FIG. 1, and is side explanatory drawing which shows the example which winds the wire 13b fixed to the outer side formwork 3b1 with the electric winding machine 14b. An outline of the overall configuration of the outer formwork 3b1 and the control mechanism of the floating roof 6 when the floating height of the floating roof 6 is measured by the liquid level gauge 28 of the form slide method for constructing a tank having a concrete wall. It is a diagram for explaining. Overall structure of control mechanism for outer formwork 3b1 and floating roof 6 when measuring the flying height with the amount of wire 13a fixed to the floating roof 6 of the form slide method for construction of a tank with a concrete wall It is a diagram for demonstrating the outline of this. It is whole side explanatory drawing which shows the example of the floating roof type tank provided with the concrete wall.

  An embodiment of a form slide method for constructing a tank having a concrete wall according to the present invention will be described with reference to FIGS. In addition, this invention is not limited only to the following embodiment. It goes without saying that the following constituent elements can be omitted or added, and the shape of the constituent elements can be changed without departing from the gist of the present invention. Moreover, the figure shows an outline, and only a part is drawn and the detailed structure is omitted.

FIG. 1 and FIG. 2 are explanatory views of the entire side of an example of a form slide method for constructing a tank having a concrete wall according to the present invention. 2 is a foundation, 3 is an outer tank, 4 is an inner tank . The tank 1 in FIG. 1 is an example of a new floating roof tank 1 having a floating roof 6 that moves up and down according to the liquid level in the inner tank 4.
This flat-shell cylindrical tank 1 having a double shell structure has a metal inner tub 4 and a concrete outer tub 3 disposed so as to surround the inner tub 4. The left side of FIG. 1 is a sectional view of the concrete outer tub 3 in the construction stage, and the right side is an external view after the concrete outer tub 3 is completed.
FIG. 1 mainly shows an example in which the floating height of the floating roof 6 is measured by the amount of winding of the wire 13a fixed to the floating roof 6 in the new tank 1, and FIG. The example in the case of measuring the flying height of the roof 6 is shown.
The inner tub 4 is installed on a concrete bottom slab 3a placed on the foundation 2, and includes a metal bottom plate 4a and a cylindrical metal side plate 4b erected on the bottom plate 4a. The top angle 7 is installed at the top of the inner tank side plate 4b. In addition, a rainwater intrusion prevention measure 9 is provided at the upper part of the inner tank side plate 4b in the height direction to prevent rainwater from entering between the inner tank side wall 4b and the outer tank side wall 3b.
The floating roof 6 is supported by a floating roof support member, such as a deck support 6f, spaced upward from the bottom plate 4a, and when the water 5 is stretched in the tank 1, the floating roof 6 moves inside the inner tank 4. It rises and floats on the surface of the water.
The floating roof 6 has a structure having a pressure bag 6a on the outer peripheral portion, floats on the water surface of the tank 1, and is slidably contacted with the inner peripheral surface of the side plate 4b so as to be movable up and down via the pressure bag 6a. Structure. The pressurization bag 6a is connected to the pressurization apparatus 6c1 which has the temporary pressure control apparatus 6c on the floating roof 6 via the temporary piping 6b. The pressure control device 6c may be installed outside the tank 1 in the case of a small tank.
The outer tub 3 has a structure comprising a concrete bottom slab 3a and a concrete outer tub side wall 3b surrounding the inner tub side plate 4b. Usually, the bottom plate 3a is constructed of reinforced concrete and the side wall 3b is constructed of prestressed concrete.

The tank 1 is provided with a mold lifting / lowering means 11 (hereinafter referred to as a mold lifting / lowering device 11) of the outer mold 3b1 at or near the top of the inner tank 4.
FIG. 1 and FIG. 2 show an example in which the mold lifting device 11 is provided on a gantry 12 temporarily provided at equal intervals in the upper part of the inner tub 4. In addition, you may use the reinforcement structure of tanks, such as an inspection frame provided in the top part or upper outer peripheral surface of the inner tank side plate 4b, or a wind girder for this frame 12.
In this mold lifting / lowering device 11, after a wire 13b having one end 13b1 fixed to the outer mold 3b1 is wound around a pulley 15b temporarily installed on the top of the mount 12, the other end 13b2 of the wire 13b is attached. It is comprised with the electric winder 14 to wind.
A wire, a rope, or the like is used for the wire 13.
A liquid level gauge 28 for measuring the liquid level in the inner tank 4 is installed in the inner tank 4 of the tank 1. FIGS. 1 and 2 show an example in which a float type liquid level gauge 28 is installed.

FIG. 3 is a flowchart for explaining the outline of the process from the start of construction of the tank 1 of the mold slide construction method for construction of the tank having the concrete wall to the completion of the installation of the mold lifting device 11. This flowchart shows an example of a process in the case of constructing a concrete outer tank side wall 3b of a new floating roof type tank.
First, in the step (A), a concrete bottom slab 3a is placed.
Subsequently, the inner tub 4 is constructed and used as the inner mold 4b for placing concrete. The inner tank 4, that is, the inner mold 4b is constructed by the following steps (B) to (C).
In the step (B), the bottom plate 4a is installed on the bottom plate 3a.
In the step (C), a cylindrical side plate 4b is constructed on the bottom plate 4a.
In the step (D), the floating roof 6 is installed on the bottom plate 4a via the deck support 6f.
In the step (E), the pressure bag 6a is annularly attached along the outer periphery of the floating roof 6. The pressurizing bag 6 a is disposed in the gap between the outer peripheral portion of the floating roof 6 and the side plate 4 b of the inner tank 4.
Then, in a process (F), the form raising / lowering apparatus 11 is temporarily installed in the top part of the inner tank side plate 4b, or the top vicinity.
Subsequently, in the step (G), the outer mold 3b1 for placing concrete is temporarily installed.
Subsequently, in step (H), after fixing one end 13b1 of the wire 13b of the mold lifting / lowering device 11 to the outer mold 3b1 and winding it around the second pulley 15b temporarily installed on the gantry 12, the other end The part 13b2 is wound around the electric winder 14.
Subsequently, in the case of the new tank 1, in step (I), the wire 13 a of the floating roof height measuring instrument 25 is fixed to the floating roof 6, and the temporary installation of the form lifting device 11 to the tank 1 is completed.

FIG. 4 is a flowchart for explaining the outline of the process from the start to the end of the construction of the concrete outer tub side wall 3b in the form slide construction method for constructing the tank having the concrete wall.
After the mold elevating device 11 is temporarily installed at or near the top of the inner tank 4, the concrete placement center height Hp is set in the control device 19 in the step (a). As shown in FIG. 2, the concrete placement center height Hp is a height obtained by adding the height Hp2 from the lower end of the concrete to be placed to the center thereof to the height Hp1 of the solidified concrete. Makes this height the same as the central height Hr of the reinforcement.
Subsequently, in step (b), a predetermined amount of water 5 is poured into the metal inner tank 4 of the tank 1 and the floating roof 6 is raised to the concrete placement center height Hp for constructing the outer tank side wall 3b. Let
Subsequently, in the step (c), the floating height of the floating roof 6 is measured by the floating roof height measuring instrument 25 that measures the liquid level of the liquid level gauge 28 or the amount of winding of the wire 13a fixed to the floating roof 6. To do. Further, the rising height of the floating roof 6 measured by the floating roof height measuring instrument 25 is transmitted to the mold lifting control means 19 (hereinafter referred to as the mold lifting control apparatus 19), and a drive signal is transmitted to the lifting drive apparatus 18. The
Subsequently, in step (d), the wire 13b fixed to the outer mold 3b1 is wound up by the electric winder 14, and the outer mold 3b1 has the same height as the floating roof 6 has floated in the step (b). It raises to the concrete placement center height Hp for the outer tank side wall 3b construction of height.
Subsequently, in the step (e), the fluid 8 is injected into the pressurizing bag 6a on the outer peripheral portion of the floating roof 6 to pressurize and expand until the inner surface of the inner tank side plate 4b is in close contact with the inner tank side plate 4b. Then, the concrete of the outer tank side wall 3b is placed to a predetermined height at which the inner tank side plate 4b between the inner tank side plate 4b and the outer mold 3b1 is not deformed.
Subsequently, in the step (f), the placed concrete is solidified.
When the concrete of the outer tub side wall 3b is not placed up to the designed height Hc, in step (g), the fluid 8 in the pressurized bag 6a of the floating roof 6 is discharged, and the pressurized bag 6a is depressurized. Then, a clearance between the inner peripheral surface of the inner tank side plate 4b and the outer peripheral part of the floating roof 6 is provided to freely move the floating roof 6 up and down, and the process returns to the step (a), and a predetermined amount of water 5 is again put into the inner tank 4. Water is additionally poured, the floating roof 6 is raised again, and the steps from the step (b) to the step (f) are performed again.
The series of steps (b) to (g) are sequentially repeated a plurality of times to construct the concrete outer tank side wall 3b having the designed height Hc.
After placing the concrete having the designed height Hc, if the outer tank side wall 3b is prestressed concrete, a tension force is applied to the concrete with a PC steel wire (not shown) or the like.
Thereafter, the inner tub 4 is drained, the floating roof 6 is lowered, the outer mold 3b1 and the mold lifting / lowering device 11 are dismantled and the construction is completed.

In this process, the floating roof 6 and the outer formwork 3b1 can be raised and lowered repeatedly in conjunction with an appropriate concrete placement height, and the concrete outer tub side wall 3b having the designed height is efficiently constructed. It is possible.
The outer mold 3b1 can be easily moved up and down in accordance with the rising height of the floating roof 6, and the outer mold 3b1 and the floating roof 6 can be easily positioned at the same height so as to face each other. Concrete can be placed in a state where the inner tank side plate 4b is appropriately reinforced against the concrete placement pressure, and the construction period can be shortened.
By repeatedly performing pressure reinforcement and concrete placement of the inner tank side plate 4b, the inner tank side plate 4b is vertically erected without deforming the inner tank side plate 4b by the concrete placement pressure Pc of the outer tank 3. It is possible to construct a concrete outer tub side wall 3b having a large design height Hc while maintaining the above.
Since the floating roof 6 of the tank 1 can be used as a reinforcing structure when placing concrete, there is no need to prepare a reinforcing material for placing concrete separately, and reinforcement is performed by attaching a reinforcing material to the entire side plate. Compared with, the workability and economy are improved, and the safety of the concrete placing work during the construction of the outer tank side wall 3b is also improved.

Further, since the side plate 4b of the newly installed or existing flat bottom cylindrical tank 1 is used as the inner mold 4b, it is not necessary to temporarily install / remove the inner mold 4b for placing the concrete side wall 3b, shortening the construction period and the construction cost. Can be reduced.
Furthermore, it is possible to carry out the water filling test of the inner tank side plate 4b with the water 5 stretched in the tank 1 in the step (b), and the construction period is shortened compared with the case where the water filling test is carried out again after completion of the tank. Can be achieved.

FIG. 5 is an enlarged view of part A in FIG. 1, and is an explanatory side view showing an example in which the wire 13 b fixed to the outer mold 3 b 1 is wound up by the electric winder 14 of the elevating drive device 18.
The wire 13b has one end 13b1 fixed to the support member 17b of the outer mold 3b1, is wound around a second pulley 15b temporarily provided on the gantry 12, and is wound around the electric winder 14b of the elevating drive device 18.
The floating roof height measuring instrument 25 includes a wire rod 13a having one end 13a1 fixed to the support member 17a at the top of the floating roof 6 and the other end 13a2 coupled to a tensioning device 16 that makes the tension constant. The tensioning device 16 includes, for example, a constant torque spring mechanism and a counterweight mechanism (both not shown).
The floating roof height measuring instrument 25 is controlled so as to keep the tension T generated in the wire 13a substantially constant so that the wire 13a does not loosen as the floating roof 6 moves up and down. The floating height position of the floating roof 6 is measured by measuring the winding length of the wire 13a electrically or optically.
You may comprise the said floating roof height measuring device 25 so that height may be measured by the rotation speed of the electric winding machine 14a, or transmission / reception of a laser.
The electric winder 14b controls the amount of rotation and the number of rotations based on the height of the floating roof 6 measured by the floating roof height measuring instrument 25, and controls the raising and lowering of the outer formwork 3b1. Water is poured into the tank 4 and the outer formwork 3b1 is raised in conjunction with the height of the floating roof 6 raised to the same height as the concrete placement center height Hp of the outer tank side wall 3b.

The pressurized bag 6a on the outer periphery of the floating roof 6 includes a fluid inlet 6d for injecting the fluid 8 into the pressurized bag 6a or discharging the fluid 8 from the pressurized bag 6a. The pressure bag 6a is connected to the fluid inlet 6d via a temporary pipe 6b, and is detachably connected to a temporary pressure control device 6c for taking in and out the fluid 8 and controlling the internal pressure. The pressure bag 6a is formed into a bag shape or a tube shape with a rubber-like elastic body laminated with a fiber reinforcing material, and a single pressure bag 6a is continuously formed in an annular shape, or a plurality of pressure bags 6a. Are connected to form an annular shape.
The procedure of pressure control when placing concrete is as follows.
First, water is poured into the tank 1, and the floating roof 6 is raised to the concrete placement center height Hp for constructing the outer tank side wall 3b that requires reinforcement of the inner tank side plate 4b.
Subsequently, the height at which the floating roof 6 in the inner tub 4 floats is measured by the floating roof height measuring instrument 25.
Subsequently, based on the height at which the floating roof 6 is levitated, the wire 13 is wound around the electric winder 14, and the outer formwork 3b1 has a concrete placement center height Hp for constructing the outer tank side wall 3b. To rise.
Subsequently, the fluid 8 (liquid or gas) is injected into the pressurizing bag 6a from the pressurizing device 6c1 having the pressure control device 6c through the pipe 6b via the fluid inlet 6d. 6a is expanded by the internal pressure Pf of the fluid so as to be in close contact with the inner peripheral surface of the inner tank side plate 4b, and the inner tank side plate 4b is pressurized and reinforced.
Subsequently, the pressure Pf of the fluid 8 injected into the pressurizing bag 6a is adjusted so that the pressure Pf of the pressurizing bag 6a of the floating roof 6 is balanced with the concrete pouring pressure Pc, and the internal pressure Pf and the concrete are adjusted. The concrete of the outer tub side wall 3b is cast to a height at which the casting pressure Pc can be balanced and solidified.
After the solidification of the concrete, the pressure control device 6c discharges the fluid 8 in the pressurization bag 6a through the pipe 6b, and reduces the internal pressure Pf of the fluid 8 in the pressurization bag 6a to the reduced pressure state. Water is injected again, and the floating roof 6 is sequentially raised to the next concrete placement center height Hp, and the outer mold 3b1 is raised in conjunction with the pressure bag 6a to expand, and the internal pressure Pf and the concrete are cast. Concrete of the outer tank side wall 3b having a height at which the installation pressure Pc is balanced is placed on the solidified concrete and solidified.
The above procedure is sequentially repeated a plurality of times to construct the concrete outer tank side wall 3b having the designed height Hc.
The pressure control device 6c discharges the fluid 8 from the pressurized bag 6a when the floating roof 6 is raised and puts it in a reduced pressure state, and when the floating roof 6 stops, injects the fluid 8 into the pressurized bag 6a and puts it in a high pressure state. Control as follows.

The outer formwork 3b1 is suspended by a plurality of formwork lifting and lowering devices 11, and is attached to the upper surface of the truss beam 3b2 and a ring-shaped truss beam 3b2 formed outside the concrete placement site of the outer tub 3. A working scaffold 3b5, a formwork support 3b4 attached to the inner peripheral surface of the truss beam 3b2, a formwork panel 3b3 attached to the inner peripheral surface of the formwork support 3b4 and in contact with the concrete, and the inner tank side plate 4b1 It comprises a guide member 3b7 that keeps a gap between the outer surface and the formwork panel 3b3, and a handrail 3b8 installed on the work scaffold 3b5.
The formwork support 3b4 is formed of H-shaped steel, groove-shaped steel, or the like, and is attached in a plurality of stages in a ring shape along the outer periphery of the formwork panel 3b3. The formwork support 3b4 and the formwork panel 3b3 are joined together by welding or the like in the circumferential direction so as to form a cylindrical shape as a whole. Further, the number, size, and position of the formwork support 3b4 and the formwork panel 3b3 are designed so as not to be affected by the concrete placing pressure of the outer tub 3.
The formwork panel 3b3 is a panel having a height larger than a single concrete placement height in the outer tub 3 divided into a plurality of heights. Moreover, it is preferable to design the height so that the lower part of the formwork panel 3b3 is in contact with the solidified concrete in the previous stage.
The working scaffolds 3b5 are connected to each other in a ring shape along the formwork support 3b4 or the formwork panel 3b3.
The guide member 3b7 has a length capable of maintaining a gap between the outer surface of the inner tub side plate 4b1 and the inner surface of the formwork panel 3b3, and is arranged horizontally in the upper part of the inner peripheral surface of the formwork panel 3b3. When the outer mold 3b1 is moved in the vertical direction, the gap between the outer peripheral surface of the inner tank side plate 4b1 and the inner peripheral surface of the mold panel 3b3 is maintained. Alternatively, a roller 3b6 may be provided at the tip of the guide member 3b7, and the roller 3b6 may be rotated to guide along the outer surface of the inner tank side plate 4b1 when the outer mold 3b1 is moved up and down.
Further, the outer mold 3b1 is made of concrete in the outer tub 3 by fastening with a wire or a turnbuckle, or by installing a holding metal fitting or a weight (none of which is shown) so as to surround the outer periphery of the outer mold 3b1. Do not swing horizontally with the driving pressure.
Reference numeral 27 denotes a reinforcing bar for placing concrete.

The inner tank side plate 4b is not deformed by balancing the inner pressure Pf of the fluid filled in the pressure bag 6a of the floating roof 6 floated in the inner tank 4 and the concrete placing pressure Pc. It is possible to construct a concrete outer tub side wall 3b having a large design height Hc while maintaining the vertical standing state.

The pressure bag 6a removes the temporary pipe 6b and the pressure control device 6c connected to the pressure bag 6a after the step (f) of solidifying the concrete side wall 3b of the outer tub 3 of FIG. The fluid injection port 6d of the pressurizing bag 6a is closed, and the pressurizing bag 6a is used as a sealing device for preventing vapor escape of stored liquid (heavy oil, etc.) when the tank 1 is used while being pressurized. Is possible.
Moreover, when using the pressurization bag 6a as a sealing apparatus, this pressurization bag 6a shall have oil resistance, a weather resistance, etc. which considered the property of the stored liquid.

  Thus, since it can divert as a tank sealing device as it is, without replacing the pressurizing bag 6a, workability and economy are improved.

  The pressurizing bag 6a may be attached to the outer periphery of the floating roof 6 as a reinforcing material for the inner tank side plate 4b and replaced with a seal device prepared separately before the tank is used.

6 and 7 are diagrams for explaining an outline of the overall configuration of the control mechanism for the outer mold 3b1 and the floating roof 6 of the mold slide construction method for constructing a tank having a concrete wall. FIG. 6 shows an example in the case of measuring the flying height by the amount of winding of the wire 13a fixed to the floating roof 6 and FIG.
The form lifting device 11 includes a floating roof height measuring device 25 for measuring the height of the floating roof 6 in the inner tub 4, and a lifting height of the floating roof 6 measured by the floating roof height measuring device 25. And a mold lifting control device 19 for controlling the outer mold 3b1 to move up and down in conjunction with the floating roof 6 to a concrete placement center height Hp for constructing the outer tank side wall 3b. ing.
In the case of FIG. 6, the floating roof height signal 24 (the liquid level height signal 24a) of the height position information of the floating roof 6 obtained based on the liquid level height measured by the liquid level gauge 28 of the floating roof 6. ) Is transmitted to the mold lifting / lowering control device 19, the lifting / lowering driving device 18 of the outer mold 3b1 is driven by the mold lifting / lowering signal 23 transmitted from the mold lifting / lowering control device 19, and the outer mold 3b1 is moved to the outer mold 3b1. The fixed wire 13b is wound up by an electric winder 14b or sent out downward, and the outer formwork 3b1 is linked with the floating roof 6 to provide a concrete placement center height for constructing the outer tub side wall 3b. Control to move up and down to Hp.
In the case of FIG. 7, the floating roof height measuring instrument 25 includes a wire 13 a having one end portion 13 a 1 fixed to the upper portion of the floating roof 6 and the other end portion 13 a 2 coupled to a tension device 16 that makes the tension constant, An electric winder 14a controlled so as to keep the tension T generated in the wire 13a substantially constant so that the wire 13a does not loosen as the floating roof 6 moves up and down, and the tension of the wire 13a is measured. A tension measuring instrument 21 for measuring the floating height of the floating roof 6 by measuring the winding length of the wire 13a electrically or optically.
After raising and lowering the floating roof 6, the wire rod 13 a is wound up by the electric winder 14 a, and when the tension detector 21 detects that the tension T is acting on the wire rod 13 a, the wire rod tension detection signal 26 is the electric motor. After being transmitted to the winder 14a, the floating roof height signal 24 is transmitted from the floating roof height measuring instrument 25 to the mold lifting control device 19, and then the mold is transmitted from the mold lifting control device 19. The electric winding machine 14b of the raising / lowering driving device 18 of the outer mold 3b1 is driven by the raising / lowering signal 23, and the wire 13b fixed to the outer mold 3b1 is wound up or sent downward by the electric winding machine 14b. The outer mold 3b1 is controlled to move up and down to the concrete placement center height Hp for constructing the outer tub side wall 3b in conjunction with the floating roof 6.

In addition, a pouring / draining valve opening / closing signal 20 is transmitted from the floating roof height measuring instrument 25 to the on / off valve 30 of the pouring / draining device 22 that adjusts the amount of water 5 to be poured / drained into the inner tank 4. When floating, the on-off valve 30 is opened and water 5 is poured into the inner tank 4 of the tank 1. When the floating roof 6 reaches the concrete placement center height Hp set and is stopped, the on-off valve 30 is turned off. Control is performed so that water is poured into the inner tub 4 when it is closed and the floating roof 6 is lowered.
Further, the floating roof height measuring instrument 25 transmits a pressure control signal 29 to the pressure control device 6c of the pressurizing bag 6a, and when the floating roof 6 is lifted, the pressure control device 6c causes the pressure control device 6c to move from the inside of the pressurizing bag 6a. After the fluid 8 is discharged and depressurized to reach the concrete placement center height Hp set by the floating roof 6 and stopped, the fluid is put into the pressure bag 6a by the pressure device 6c1 of the pressure control device 6c. Control to inject 8 and pressurize.

  By feeding back the height information of the floating roof 6 in the inner tank 4 and adjusting the amount of water 5 poured into and drained into the inner tank 4 and the internal pressure of the pressurized bag 6a, the concrete of the designed height Hc. The construction work of the made outer tank side wall 3b is made efficient.

Further, as an apparatus for lifting the outer mold 3b1, a climbing jack, an electric winch, or the like can be used instead of the electric winder 14.

The form slide construction method for the construction of the concrete outer tank side wall of the tank with the concrete wall is a fixed roof tank that is desired to improve the seismic performance of the tank in the event of an earthquake, especially for measures against tsunami from the outside, The present invention can be applied to a structure such as a storage other than a tank, and is particularly effective for a structure in which a concrete outer tank side wall having a large design height needs to be placed.

1 tank
2 Basics
3 Outer tank 3a (made of concrete) Bottom plate 3b Side wall 3b1 Outer formwork 3b2 Truss beam 3b3 Formwork panel 3b4 Formwork support part 3b5 Working scaffold 3b6 Roller 3b7 Guide member 3b8 Handrail 4 (made of metal) Inner tank 4a Bottom plate 4b Side plate (inner formwork)
5 Water 6 Floating roof 6a Pressure bag 6b Piping
6c Pressure control device 6c1 Pressurization device 6d Fluid inlet 6e Top plate 6f Deck support 7 Top angle 8 Fluid (liquid or gas)
9 Measures to prevent rainwater intrusion 10 Stock solution
11 Form lifting device (means)
12 Base 13 (for installing the form lifting device) Wire 13a Wire 13a1 of the floating roof 6 One end 13a2 of the wire 6 of the floating roof 6 Other end 13b of the wire 6 of the floating roof 6 Wire 13b1 of the outer mold 3b1 One end portion 13b2 of the wire rod The other end portion 14 of the wire rod of the outer mold 3b1 The electric winder 14a The electric winder 14b of the floating roof 6 The electric winder 15 of the outer mold 3b1 (of the mold lifting device 11) 15a first pulley 15b second pulley 16 tensioning device 17 support member 17a support member 17b (of floating roof 6) support member 18 (outside mold 3b1) support member 18 mold lifting / lowering drive device 19 mold lifting control device (means)
20 Pouring drain valve opening / closing signal 21 Tension detector 22 of wire rod 13a Pouring / draining device 23 Form lifting signal 24 Floating roof height signal 24a Liquid level height signal 25 Floating roof height detector 26 Wire rod tension signal 27 Rebar 28 Liquid Surface meter 28a Float 28b Float box 28c Guide pipe 28d Support 28e Measuring wire 28f Gauge pole 29 Pressure control signal 30 On-off valve

Design height of Hc concrete side wall 3b External pressure Pf of concrete casting Pf Pressure of fluid filled in pressurized bag 6a T Tension applied to slackened wire 13 Hr Reinforcement center height Hp Concrete placement center height Hp1 Solidification Height Hp2 of the finished concrete Height from the lower end (or upper end) of the concrete to be placed to the center

Claims (4)

In the construction of a flat bottom cylindrical tank having a concrete outer tub arranged around a metal inner tub, the inner tub is a newly constructed metal flat bottom cylindrical tank or an existing metal tub. A flat bottom cylindrical tank, wherein the side plate of the metal inner tub is used as an inner mold for placing concrete in the side wall construction of the concrete outer tub, and is formed on the outer periphery of the cylindrical inner mold. Temporary formwork for placing concrete used for the construction of the outer tank side wall, and raising and lowering the formwork in conjunction with the raising and lowering of the metal floating roof installed in the inner tank A formwork slide construction method for constructing a concrete side wall provided with means, wherein a plurality of formwork raising and lowering means for temporarily suspending the outer formwork is temporarily mounted on a pedestal temporarily installed near or at the top of the inner tank side plate. And then pour water into the inner tank The root is raised to the concrete placement height for constructing the outer tank side wall, and the outer formwork is raised to a height opposite to the floating roof in conjunction with the rise of the floating roof by the plurality of formwork raising and lowering means. Designing and repeating the step of placing and solidifying the concrete between the inner tank side plate and the outer mold, while reinforcing the inner tank side plate with the floating roof and the pressure bag The construction method of the flat bottom cylindrical tank provided with the concrete wall characterized by constructing the concrete outer tank side wall of the height made from the lower part to the upper part.
The mold lifting / lowering means includes a wire rod having one end fixed to the outer mold frame, a lift driving device including an electric winder capable of winding or lowering the wire rod, and the metal inner tank. A floating roof height measuring instrument for measuring the floating height of the floating roof that floats by water injection, and an electrical signal related to the height position information of the floating roof measured by the floating roof height measuring instrument And a control device of the lifting drive device that can control the lifting height of the outer formwork, and linked to the electric winder in conjunction with the floating of the floating roof with the wire rod 2. The method for constructing a flat bottom cylindrical tank with a concrete wall according to claim 1, wherein the outer mold is a form raising / lowering means capable of winding up or down.
The floating roof height measuring instrument has one end fixed to the upper part of the floating roof and the other end coupled to a tensioning device that makes the tension constant, and loosening of the wire accompanying the lifting and lowering of the floating roof An electric winder that is controlled so as to keep the tension generated in the wire substantially constant so as not to occur, and by measuring the winding length of the wire electrically or optically, It is a floating roof height measuring instrument for measuring the floating height position of the floating roof, or a floating roof height measuring instrument using an existing liquid level gauge provided in the existing flat bottom cylindrical tank, 3. The concrete wall according to claim 1, wherein an electrical signal related to the measured height position information of the floating roof is transmitted to a control device of a lift driving device for lifting and lowering the outer formwork. A construction method for a flat-bottomed cylindrical tank.
The floating roof includes a single or a plurality of detachably attached pressure bags that are continuously connected in an annular shape along an outer peripheral portion of the floating roof, and the pressure bag is disposed in the pressure bag. A fluid inlet for injecting fluid or discharging the fluid from the pressurized bag is provided, and connected to the fluid inlet via a pipe, and the fluid is taken in and out of the pressurized bag. A pressure bag detachably connected to a pressure device having a pressure control device for controlling an internal pressure, wherein the inner tank side plate according to claim 1 is reinforced with the floating roof and the pressure bag, In the step of casting and solidifying the concrete between the tank side plate and the outer formwork, according to the placement height of the concrete, so as to be able to counteract the placement height pressure of the concrete to be placed at once. Inject fluid into the pressurized bag to After the pressure bag is inflated so as to be in close contact with the inner surface of the inner tank and the side surface of the floating roof, the inner tank side plate is pressurized and reinforced from the inner surface side, and the concrete on the outer tank side wall is solidified. The fluid pressure is controlled by discharging the fluid from the inside of the pressurized bag and reducing the pressure inside the pressurized bag so as to freely move the floating roof up and down for the next step. A construction method of a flat bottom cylindrical tank provided with the concrete wall according to 1.

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