JP2587383B2 - Underground storage tank construction method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction method of an underground low-temperature storage tank for storing a low-temperature liquid such as LNG.

[0002]

2. Description of the Related Art Conventionally, a construction method of an underground storage tank for storing a low-temperature liquid such as LNG is to construct a cylindrical concrete tank body with a bottom in the basement and then construct a dome-shaped roof structure. Installed in the upper opening of the tank body by jack-up method, air-raising method or lateral movement,
Thereafter, a cold insulator and a membrane were attached to the inner wall of the tank body. (See, for example, JP-A-63-92896, JP-A-51-117312, and JP-A-4-258597.)

[0003]

According to the above-mentioned conventional underground storage tank construction method, a cylindrical tank body is first constructed, and after the tank body is completed, a roof structure is constructed. This was a procedure of mounting the cold insulator and membrane, and required a lot of construction time. In addition, the number of days when work is impossible due to rain during that period has reached about 15%.

An object of the present invention is to use a roof structure having a half dome structure as a retractable construction roof by using lateral movement of the roof structure, and to eliminate work inoperable days due to rain during the construction period of a tank body. The aim is to provide a construction method that can significantly reduce the time.

[0005]

According to the structure of the present invention which solves the problems of the prior art, a cylindrical concrete tank is constructed underground, and a dome-shaped roof structure is attached to the upper opening of the tank. In the construction method of an underground storage tank, when excavating the basement and constructing a cylindrical tank body, the roof structure of a half dome structure consisting of a pair of two pieces constructed in parallel with this work The upper opening of the tank body can be opened and closed, and both roof components are used as openable construction roofs during the construction of the tank body, and after the completion of the construction of the tank body, the roof body as an integrated dome structure roof structure It is installed in.

[0006]

[Function] Assemble the roof structure of the half dome structure, transport it to the vicinity of the tank body, lay a rail from the vicinity of the tank body to the upper opening of the tank body, and place a carriage on it to enable lateral movement State. The roof structures of the half-dome structure, which are abutted to each other, are aligned with each other at the top of the tank body by lateral movement, and are separated from each other to be used as an openable roof for construction during the construction of the tank body. By eliminating impossible days, the construction period can be significantly reduced. Further, since a roof portion installed on the upper opening of the tank body is used as a construction roof, no material is required as a roof material. As for the materials, the rails and bogies that were installed for the installation are simply installed continuously during the construction period of the tank body, and the openable roof can be used.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 is an explanatory view showing excavation work of a tank body at a construction site of an underground storage tank, FIG. 2 is an explanatory view of a state in which a tank body is being constructed while using a roof structure having a half dome structure as an opening / closing roof, FIG. 3 is an explanatory view of a state in which the roof structure is used as an opening / closing roof, and then installed in an upper opening.
4 is a side view of the roof structure, FIG. 5 is a cross-sectional view of a joint of the roof structure, FIG. 6 is a cross-sectional view of an outer peripheral portion of the roof structure, and FIG. 7 shows means for laterally moving the roof structure having a half-dome structure. Plan view,
FIG. 8 is a side view of a receiving stand and a suspension bracket, FIG. 9 is a side view of a mounting stand, FIG. 10 is a side view of a transport vehicle loaded with a roof structure having a half-dome structure, and FIG. It is a side view of the trolley which performs lateral movement.

As shown in FIGS. 1 and 2, in the construction method of an underground storage tank according to the present invention, an underground is excavated while a continuous wall 1 is installed, and then a construction work of a cylindrical concrete tank body 2 is performed. At the same time, the roof component 3 having the half-dome structure is assembled and the rail 13 is laid in the vicinity of the tank 2, and the roof component 3 having the half-dome structure is inserted into the upper opening 2a of the concrete tank 2. It can be opened and closed and can be moved horizontally. Also,
The ends of the roof dome 3 having a half-dome structure are arranged as shown in FIGS. 5 and 6 so that rain and wind do not enter the tank 2 when they are joined together by the upper opening 2a. A rainproof curtain 7 is installed. In the drawing, reference numeral 8 denotes a curtain bracket. When the preparation for the lateral movement of the roof structure 3 is completed,
Since the construction work for tank body 2 has only been completed for about 1/3 of the whole, the above roof is used as an openable construction roof as shown in Fig. 2 during the remaining 2/3 construction period. I do. Thereafter, after the construction work of the tank body 2 is completed, the openable / closable construction roof structures 3 are butted against each other as shown in FIG. 3, and the joined portions are joined to be installed as an integral dome-shaped roof structure 4. The tank body 2 stores a low-temperature liquid such as LNG, and is formed of concrete into a cylindrical shape having a diameter of about 70 m.
a is buried underground so that it is almost parallel to the ground surface.
The roof structure 4 covers the upper opening 2a of the tank body 2 and is formed by assembling materials such as a roof plate 6 and a roof bone 5 into a dome shape as shown in FIG.

Next, the transportation and movement of the present invention will be described in detail. FIG. 7 shows a plan view when the roof structure having the half dome structure is laterally moved and a plan view when the roof portion assembled into a half dome shape at another place is transported to the vicinity of the tank body 2. First, the plan view on the right side of the paper surface of FIG. 7 shows a case where the roof structure 3 having the half-dome structure assembled at another place is transported to the vicinity of the tank body 2. Temporary pillars 10 that are arranged in the lower two places of the roof component 3 having a half-dome structure and that serve as the roof component 3 are loaded. FIG. 10 shows the packing state at that time. The transport vehicle 9 has a number of rows of tire-like wheels 16 and has a structure capable of withstanding heavy loads. Further, the suspension portion of the axle is provided with a hydraulic jack mechanism 17 so that it can overcome a certain degree of road undulation while receiving a heavy load. Of course, it is possible to freely turn by operating the steering wheel. Further, since the transport vehicle 9 can move up and down the entire cargo bed by about 60 using the hydraulic jack mechanism, the truck 18 is placed under the roof structure 3 and then the cargo bed 18 is raised to receive the load of the whole roof structure 3. The roof component 3 can be lifted and transported to the vicinity of the tank 2. In the plan view on the right side of the paper of FIG. 7, after the roof component 3 having the half-dome structure is transported to the vicinity of the tank body 2 by two transport vehicles 9, the whole of the loading platform 18 is lowered by the above-described hydraulic jack mechanism 17. The roof structure 3 is lowered and placed on the receiving stands 11 arranged at three places.
FIG. 8 is a side view of the gantry 11, in which a suspension bracket 12 is attached and fixed to the roof structure 3 in advance. The suspension bracket 12 is to be removed after the installation of the roof structure 4 is completely completed. . On the other hand, in FIG.
At the same time that the roof structure 3 is mounted on the gantry 11,
Fastening bolt 1 fixing temporary pillar 10 and roof structure 3
Remove 9 Further, the loading platform 18 by the hydraulic jack mechanism 17
After that, the load of the entire roof structure 3 is applied to the support base 11 and the lowering of the bed is stopped when a gap is formed between the temporary pillar 10 and the roof structure 3. Returning to FIG. 7, the transport vehicle 9 travels in the direction of the arrow b and retreats from the vicinity of the tank body 2. Also, the temporary rail 13 is temporarily removed only at the portion where the transport vehicle 9 runs, and the temporary rail 13 is later connected and returned. In the same manner, the roof component 3 having the half dome structure on the opposite side of the tank body 2 is transported and arranged near the tank body 2. The above is the description of transporting the roof structure having the half-dome structure from another place.

Next, from the vicinity of the tank body, the upper opening 2 of the tank body 2 is opened.
A method of laterally moving the roof structure 3 to a will be described with reference to a plan view on the left side of the paper of FIG. First, two laterally movable trolleys 14 are arranged on both sides of the receiving stand 11 on which the roof structure 3 is mounted, and the trolleys 14 are mounted via the wheels 20 on the temporary rails 13 laid in advance. Have been. FIG. 11 is a side view of the trolley performing the lateral movement. The bogie 14 has a hydraulic jack 21 mounted thereon.
3 is extended. Two laterally moving trolleys 14
After the arrangement is completed, the receiving beam 15 connecting the truck 14 is placed on the upper part of the cylinder 23 of both hydraulic jacks 21, and the suspension wire 22 is lowered from the center thereof and attached to the suspension bracket 12. After the mounting of the carriage 14, the receiving beam 15, and the suspension wire 22 is completed on the portion of the support base 11 that receives the roof dome 3 having the half dome structure at three locations, the cylinders 23 of the hydraulic jack 21 are simultaneously mounted. The entire roof structure 3 is extended upward and lifted from the gantry 11. After the entire levitation is completed, the cradle 11 is lifted from the temporary rail 13 by a crane waiting nearby and removed. In FIG. 7, after the removal of the three receiving stands 11 is completed, the roof structure 3 having the half-dome structure is simultaneously moved on the temporary rail 13 and moved laterally to the upper opening 2 a of the tank 2. After that, the removed gantry 11 is placed under the suspension bracket 12 attached to the roof structure 3 using a mobile crane. After the three locations are completed, the cylinders 23 of the hydraulic jacks 21 mounted on the carriage 14 are simultaneously contracted, and the entire roof structure 3 is lowered, mounted on the receiving stand 11 and once fixed. FIG. 11 is a side view thereof. The above procedure is also performed on the roof structure 3 having a half-dome structure on the opposite side of the tank body, and the roof structure 4 having a dome shape is combined with each other, and the rainproof curtain 7 shown in FIGS. At the end of the roof. In this state, the construction work of the tank body 2 can be performed even on a day such as rain. In addition, by repeating this operation, it can be used as an openable roof during the construction period of the tank body 2,
After use, it is installed as an integral dome-shaped roof.

Next, the installation will be described in detail.
At the stage when the construction work of the tank body 2 is completed, the installation stand 24 is arranged on the circumference of the tank body 2 as shown in FIG. As shown in FIG. 9, this mounting base 24 is mounted on the upper surface of the constructed tank body 2, and is embedded with post-cast concrete 25 after the installation of the roof is completed. The installation of the roof part is performed by laterally moving the roof dome structure 3 having the half dome structure to be combined in accordance with the above-mentioned procedure, closing the roof opening body 3 at the upper opening 2a, and mounting it on the installation gantry 24 instead of the receiving gantry 11.
FIG. 9 is a side view thereof. After that, the butt joint portions of the roof component 3 having the half dome structure are joined to complete an integrated dome-shaped roof, and the installation is completed. As described above, the heavy roof can be easily opened and closed by the present embodiment, so that the roof can be used as a construction roof during the construction period of the tank body. The above-described method using a laterally moving cart is an example, and various other mechanisms are naturally conceivable. For example,
It is also possible to use a chill tank, Teflon, compressed air, etc.

[0012]

According to the configuration of the present invention as described above, the following effects can be obtained. (A) Since the roof structure with a half-dome structure can be used as an openable roof for construction, work days due to rain during the construction period of the tank are eliminated, and the construction period of the underground storage tank is greatly reduced. can do. (B) Since the construction roof is installed in the upper opening after the construction of the tank body is completed, no new roof material is required for the construction. (C) The required materials are rails, trolleys, and cradle bases that are installed for installation, and can be used as long as the openable roof can be used if they are installed continuously during the construction of the tank body. Becomes (D) Since the roof component installed in the upper opening can be used as a construction roof as it is, there is no need to assemble and disassemble the construction roof.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing excavation work of a tank body at a construction site of an underground storage tank.

FIG. 2 is an explanatory diagram of a state in which a tank body is being constructed while using a roof component having a half-dome structure as an openable roof.

FIG. 3 is an explanatory view of a state where the roof structure is used as an openable roof and then installed in an upper opening.

FIG. 4 is a side view of the roof structure.

FIG. 5 is a cross-sectional view of a joint part of a roof structure.

FIG. 6 is a cross-sectional view of an outer peripheral portion of a roof structure.

FIG. 7 is a plan view showing a means for laterally moving a roof structure having a half-dome structure.

FIG. 8 is a side view of the cradle and the suspension bracket.

FIG. 9 is a side view of the mounting base.

FIG. 10 is a side view of a transport vehicle loaded with a roof structure having a half-dome structure.

FIG. 11 is a side view of a bogie for performing lateral movement of the roof structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Continuous wall 2 Tank body 2a Upper opening part 3 Roof structure 4 Roof structure 5 Roof bone 6 Roof board 7 Rainproof curtain 8 Curtain bracket 9 Transport vehicle 10 Temporary pillar 11 Receiving stand 12 Suspension bracket 13 Temporary rail 14 Dolly 15 Receiving Beam 16 Wheel 17 Hydraulic jack mechanism 18 Luggage carrier 19 Fastening bolt 20 Wheel 21 Hydraulic jack 22 Hanging wire 23 Cylinder 24 Installation stand 25 Post-cast concrete

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-131595 (JP, A) JP-A-63-163096 (JP, A)

Claims (1)

(57) [Claims] In a construction method of an underground storage tank in which a cylindrical concrete tank body is constructed underground and a dome-shaped roof structure is attached to an upper opening of the tank body, an underground is excavated to form a cylindrical tank body. When performing the construction work, the upper opening of the tank body can be opened and closed by moving the roof structure of the half dome structure consisting of two sets constructed in parallel with this construction An underground storage tank construction method characterized in that it is used as an openable roof for construction during the construction period of the tank body, and after the construction of the tank body is completed, it is installed on the tank body as a one-piece dome structure roof structure.