Modular prestressed storage tank and installation method

Abstract

The application discloses a modular prestressed storage tank and a mounting method, relates to the technical field of storage tank construction, and realizes rapid, efficient and high-quality construction by decomposing a storage tank wall into standardized prefabricated module units and adopting innovative prestressed connection and super-high-performance concrete pouring on site. The construction mode not only greatly shortens the construction period, reduces the construction risk, improves the construction precision and safety, but also significantly enhances the overall structural integrity and airtightness of the storage tank, and provides a more advanced and reliable solution for large-scale storage of LNG and other media.

Description

Technical Field

[0001] This invention relates to the field of storage tank construction technology, and more specifically to a modular prestressed storage tank and its installation method. Background Technology

[0002] Liquefied natural gas (LNG), as a clean and efficient energy source, plays a crucial role in environmental protection and energy efficiency through its storage technology. In the LNG industry chain, LNG storage is vital for balancing production and consumption; therefore, the construction of LNG storage tanks is of paramount importance to the development of the entire industry. With the advancement of the low-carbon economy and the optimization and upgrading of the energy structure, the LNG industry has enormous future development potential.

[0003] Currently, the construction period for large LNG storage tanks is generally quite long. For example, the typical construction period for a large concrete full-containment LNG storage tank is between 30 and 36 months. This is mainly due to the prestressed cast-in-place reinforced concrete structure commonly used in existing technologies, which has a complex construction process and usually involves layered pouring. Specifically, this includes steps such as rebar tying, formwork support, concrete pouring, and curing, with each layer taking approximately 10 days to complete. Based on the number of layers in the tank wall of a large LNG storage tank, the entire tank wall construction period could be as long as 120 days. This lengthy construction period not only increases the overall time cost of the project but also further extends the construction period under adverse weather conditions such as the winter shutdown in northern regions and the typhoon season in southern coastal areas. Furthermore, this cast-in-place construction method involves prolonged high-altitude work, posing potential safety hazards to construction workers, and the quality and precision of on-site construction are difficult to fully guarantee.

[0004] While prefabricated storage tanks can shorten construction cycles, improve construction convenience and safety, and enhance precision and quality to some extent, existing prefabricated storage tanks often have gaps at the connections between modules, resulting in insufficient overall airtightness and poor structural integrity. In the event of an LNG leak, this could pose serious safety risks, limiting its application in large-scale, high-safety-requirement storage tanks. Therefore, existing technologies still have significant shortcomings and deficiencies in addressing issues such as long construction cycles, difficulty in ensuring construction quality, safety hazards for construction workers, and insufficient airtightness of prefabricated storage tanks.

[0005] Therefore, it is necessary to propose a modular prestressed storage tank and its installation method to solve the above problems. Summary of the Invention

[0006] The purpose of this invention is to solve the problems of long construction cycle, difficulty in ensuring construction quality, and safety hazards for construction personnel in conventional cast-in-place construction methods in the prior art, while overcoming the problems of large gaps between modules and insufficient airtightness in existing prefabricated storage tanks.

[0007] To achieve the above objectives, the present invention specifically adopts the following technical solution:

[0008] A modular prestressed storage tank and its installation method, comprising:

[0009] The tank wall and the bottom plate;

[0010] The tank wall is composed of several tank wall module units, each of which is arc-shaped.

[0011] The tank wall module unit includes an inner steel plate unit and a concrete unit. The inner steel plate unit is provided with a plurality of studs, and the concrete unit is fixed to the inner steel plate unit by the studs.

[0012] A staggered positioning area is formed between the concrete unit and the inner steel plate unit. The left and right staggered positioning areas between every two adjacent tank wall module units form a horizontal connection area, and the upper and lower staggered positioning areas form a vertical connection area. The horizontal connection area and the vertical connection area are connected.

[0013] The concrete unit has an operating hole at the middle of the upper and lower arc edges. The operating hole is provided with a horizontal module connection channel, a horizontal prestressing channel, a vertical module connection channel, and a vertical prestressing channel for connecting multiple tank wall module units.

[0014] The bottom plate of the tank has a bottom plate positioning groove for installing the bottommost tank wall module unit.

[0015] Furthermore, it also includes horizontal connecting steel strands, horizontal prestressed steel strands, vertical connecting steel strands, and vertical prestressed steel strands, all of which are connected to anchors at both ends, for applying prestress to the steel strands;

[0016] The horizontal connecting steel strands are threaded through the horizontal module connecting channels, the horizontal prestressed steel strands are threaded through the horizontal prestressing channels, the vertical connecting steel strands are threaded through the vertical module connecting channels, and the vertical prestressed steel strands are threaded through the vertical prestressing channels.

[0017] Furthermore, the joints between the tank wall module units and the connection area between the tank wall module unit and the bottom plate of the tank are filled with ultra-high performance concrete.

[0018] Furthermore, the bottom plate positioning groove is connected to the horizontal connection area of ​​the tank wall module unit.

[0019] An installation method for a modular prestressed storage tank, comprising the aforementioned modular prestressed storage tank, further comprising the following steps:

[0020] 1) Prefabricate tank wall modules in the factory, cure them to the design strength, and then transport them to the construction site;

[0021] 2) After the anchors and initial steel strands are installed at the construction site, concrete is poured to form the bottom plate of the tank. After the bottom plate of the tank has been cured to the design strength, preparations for hoisting are made.

[0022] 3) Use a crane to hoist the first layer of tank wall module unit into place, and temporarily fix it by aligning its bottom with the positioning groove of the bottom plate of the tank bottom plate;

[0023] 4) Insert the horizontal connecting steel strands, horizontal prestressed steel strands, vertical connecting steel strands, and vertical prestressed steel strands into the corresponding ducts, install the anchorages, and then tension the steel strands to the predetermined prestress value.

[0024] 5) Inject ultra-high performance concrete into the horizontal connection area of ​​the first layer tank wall module unit and the annular gap formed by the bottom of the tank wall module unit and the positioning groove of the bottom plate to realize the connection between the tank wall module unit and the bottom plate of the tank.

[0025] 6) Following the methods in steps 3) to 5), install the subsequent tank wall module units in sequence. After each tank wall module unit is installed, pour ultra-high performance concrete into the horizontal connection area of ​​that tank wall module unit and the vertical connection area between that layer and the next layer until the installation of all tank wall module units is completed.

[0026] Further, in step 1), the factory prefabrication includes: fabrication of the inner steel plate unit, welding of the studs and casting of the concrete unit, and reserving in the concrete unit a staggered positioning area, operating hole, horizontal module connection channel, horizontal prestressing channel, vertical module connection channel and vertical prestressing channel.

[0027] Furthermore, in step 2), the on-site construction of the tank bottom plate includes: pre-embedding initial vertical connecting steel strands and vertical prestressed steel strands in a certain area of ​​the tank bottom plate.

[0028] Furthermore, in step 3), the temporary fixing is achieved by aligning the structure at the bottom of the tank wall module unit with the bottom plate positioning groove of the tank bottom plate, while the misalignment positioning area is used to assist in positioning and temporary fixing.

[0029] Furthermore, in step 4), the lower ends of the vertical connecting steel strand and the vertical prestressed steel strand are connected to the anchors and steel strands pre-embedded in the bottom plate of the tank.

[0030] Furthermore, in step 5), after the ultra-high performance concrete is poured, the next layer of tank wall module unit can be installed without waiting for curing.

[0031] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0032] The modular prestressed storage tank and its installation method provided by this invention achieve rapid, efficient, and high-quality construction by decomposing the tank wall into standardized prefabricated modular units and employing innovative prestressed connections and ultra-high-performance concrete pouring on-site. This construction method not only significantly shortens the construction period, reduces construction risks, and improves construction accuracy and safety, but also significantly enhances the overall structural integrity and airtightness of the storage tank, providing a more advanced and reliable solution for the large-scale storage of media such as LNG. Attached Figure Description

[0033] Figure 1 This is a three-dimensional schematic diagram of the modular prestressed storage tank in this invention.

[0034] Figure 2 This is a top view of the modular prestressed storage tank during installation in this invention.

[0035] Figure 3 This is a side view of the modular prestressed storage tank during installation in this invention.

[0036] Figure 4 This is a top view of the tank wall module unit in this invention.

[0037] Figure 5 This is a side view of the tank wall module unit in this invention.

[0038] Reference numerals: 1. Tank wall module unit; 2. Tank bottom plate; 3. Inner steel lining unit; 4. Concrete unit; 6. Stud; 7. Horizontal module connection channel; 8. Horizontal prestressed channel; 9. Vertical module connection channel; 10. Vertical prestressed channel; 11. Operating hole; 12. Horizontal connection area; 13. Bottom plate positioning groove; 14. Vertical connection area; 15. Horizontal connecting steel strand; 16. Horizontal prestressed steel strand; 17. Vertical connecting steel strand; 18. Vertical prestressed steel strand; 19. Anchor. Detailed Implementation

[0039] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0040] Please see Figures 1 to 5This invention provides a modular prestressed storage tank and its installation method. The main structure of the storage tank includes a tank wall section and a tank bottom plate section 2. The tank wall section is composed of several tank wall module units 1 arranged in a ring. Each tank wall module unit 1 is arc-shaped, and its internal structure consists of two parts: an inner steel plate lining unit 3 and a concrete unit 4. When the tank wall module unit 1 is prefabricated in the factory, multiple studs 6 are pre-installed on the inner steel plate lining unit 3. The studs 6 are usually fixed to the inner steel plate lining unit 3 by welding. When the concrete unit 4 is poured, the studs 6 are embedded in the concrete, thereby forming a reliable fixation between the inner steel plate lining unit 3 and the concrete unit 4, enabling them to work together to form a complete tank wall module unit 1.

[0041] A staggered positioning area is formed around the concrete unit 4 and the inner steel plate unit 3. This allows for pre-reserved gaps to be created when assembling the tank wall module unit 1. Specifically, the staggered positioning areas on the left and right sides between every two adjacent tank wall module units 1 form a horizontal connection area 12 for vertical connection and grouting between modules; the staggered positioning areas on the upper and lower sides form a vertical connection area 14 for horizontal connection and grouting between modules. The horizontal connection area 12 and the vertical connection area 14 are interconnected, ensuring that the grouting material can fully fill the connection space. The staggered positioning area also plays a role in auxiliary positioning and temporary fixation during assembly, ensuring precise alignment of the tank wall module unit 1.

[0042] Combination Figure 4 and Figure 5 As shown, concrete unit 4 is divided into an outer layer and an inner layer. The inner layer is offset to the lower right corner of the outer layer, i.e., the lower and right ends of the inner layer, and is not covered by the outer layer and the inner lining steel plate unit 3. An operating hole 11 is provided in the middle of the upper and lower arc edges of the inner layer. It is used for threading and tensioning steel strands after the module is hoisted and temporarily fixed. The operating hole 11 is provided with reserved channels, including horizontal module connection channel 7, horizontal prestressing channel 8, vertical module connection channel 9, and vertical prestressing channel 10. These channels are pre-formed in the factory and are used for subsequent threading of horizontal connecting steel strands 15, horizontal prestressing steel strands 16, vertical connecting steel strands 17, and vertical prestressing steel strands 18. Prestress is applied by tensioning these steel strands under the action of anchors 19 at both ends, thereby realizing the horizontal and vertical connection between the tank wall module units 1 and forming an integral prestressed structure.

[0043] The bottom plate portion 2 of the tank has an annular positioning groove 13. The shape and size of the positioning groove 13 match the bottom structure of the tank wall module unit 1, and are used for precise alignment and temporary restraint when installing the bottommost tank wall module unit 1. After the bottommost tank wall module unit 1 is installed, an annular gap will be formed between the bottom of the tank wall module unit 1 and the bottom plate 2 of the tank. This gap communicates with the horizontal connection area 12 of the tank wall module unit 1 for pouring ultra-high performance concrete.

[0044] The installation method for the modular prestressed storage tank provided by this invention includes the following steps:

[0045] Step 1: Factory Prefabrication of Tank Wall Modules. In a specialized prefabrication plant, tank wall module units 1 are industrially produced according to design requirements. This includes the fabrication of the inner steel lining unit 3, the welding of the studs 6, and the casting of the concrete unit 4. During the casting of the concrete unit 4, precise pre-reserved misalignment areas, operating holes 11, horizontal module connection channels 7, horizontal prestressing channels 8, vertical module connection channels 9, and vertical prestressing channels 10 are provided. All module units are cured under strict quality control until they reach their design strength, ensuring their structural performance and dimensional accuracy, before being transported to the construction site.

[0046] Step 2: On-site construction of the tank bottom plate. At the tank construction site, the foundation construction is completed first. Next, within the area of ​​the tank bottom plate section 2, necessary anchors 19 and initial vertical connecting steel strands 17 and vertical prestressed steel strands 18 are pre-embedded. These steel strands will be used for subsequent vertical connections with the tank wall module unit 1 and for applying prestress. Then, concrete is poured to form the tank bottom plate 2 and fully cured to reach its design strength. The pre-reserved positioning grooves 13 on the tank bottom plate 2 should be kept clean and precise.

[0047] Step 3: Hoisting and Installing the First Layer Tank Wall Module Unit. Using large cranes or other specialized lifting equipment, the prefabricated first layer tank wall module unit 1 is precisely hoisted onto the tank bottom plate 2. During the hoisting process, the bottom structure of the tank wall module unit 1 is aligned with the positioning groove 13 of the bottom plate 2 to achieve precise installation and temporary fixation of the module. Simultaneously, the staggered positioning area around the tank wall module unit 1 also serves as an auxiliary positioning and temporary fixation feature at this stage, ensuring the spacing and alignment between adjacent modules.

[0048] Step 4: Threading and Tensioning the Steel Strands. After the first layer of tank wall module unit 1 is temporarily fixed in place, internal operations are carried out through the operating hole 11. The horizontal connecting steel strand 15 and the horizontal prestressed steel strand 16 are threaded into the horizontal module connection channel 7 and the horizontal prestressing channel 8, respectively. Simultaneously, the vertical connecting steel strand 17 and the vertical prestressed steel strand 18 are threaded into the vertical module connection channel 9 and the vertical prestressing channel 10. The lower ends of these vertical steel strands are connected to the anchors 19 pre-embedded in the bottom plate 2 of the tank. After the steel strands are threaded, the corresponding anchors 19 are installed at the outlet of each channel. Then, specialized tensioning equipment is used to tension the steel strands to achieve the predetermined prestress value, thereby realizing the horizontal and vertical connections between the tank wall module units 1 and applying prestress to the tank structure.

[0049] Step 5: Pouring Ultra-High Performance Concrete. After the steel strands of the first layer tank wall module unit 1 are tensioned, ultra-high performance concrete is poured into the horizontal connection area 12 of the first layer tank wall module unit 1 and the annular gap formed by the bottom of the tank wall module unit 1 and the bottom plate positioning groove 13 through the operating hole 11. Ultra-high performance concrete has excellent fluidity, high strength, and density. During the pouring process, ensure that the ultra-high performance concrete completely fills the horizontal connection area 12 and the bottom plate positioning groove 13 to form a dense connection layer.

[0050] Step 6: Repeat the installation of subsequent tank wall module units. Following the process described in steps 3 to 5 above, install the second, third, and finally the last tank wall module unit 1 in sequence. After the subsequent tank wall module unit 1 is installed and tensioned, ultra-high performance concrete is poured into the horizontal connection area 12 of that tank wall module unit 1. Since the horizontal connection area 12 and the vertical connection area 14 are interconnected, the ultra-high performance concrete will flow into the vertical connection area 14. The ultra-high performance concrete will fill these areas sequentially, forming a continuous and dense connection. After the ultra-high performance concrete is poured, no curing is required, and the installation of the next module can proceed immediately, thus greatly accelerating the construction progress. Repeat this process until all tank wall module units 1 are installed, ultimately forming a complete, high-strength, and highly airtight modular prestressed storage tank.

[0051] This invention fundamentally solves the problems of long construction cycle, high construction safety risks, difficult quality control, and poor airtightness of existing prefabricated tanks by using a strategy of factory prefabrication, rapid on-site assembly, and ultra-high performance concrete connection, thus realizing the industrial upgrading of LNG storage tank construction.

[0052] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. The scope of patent protection of the present invention shall be determined by the claims. Similarly, any equivalent structural changes made based on the content of the present invention's specification shall also be included within the scope of protection of the present invention.

Claims

1. A modular prestressed storage tank, characterized in that, Including the tank wall and the tank bottom plate; The tank wall is composed of several tank wall module units, each of which is arc-shaped. The tank wall module unit includes an inner steel plate unit and a concrete unit. The inner steel plate unit is provided with a plurality of studs, and the concrete unit is fixed to the inner steel plate unit by the studs. A staggered positioning area is formed between the concrete unit and the inner steel plate unit. The left and right staggered positioning areas between every two adjacent tank wall module units form a horizontal connection area, and the upper and lower staggered positioning areas form a vertical connection area. The horizontal connection area and the vertical connection area are connected. The concrete unit has an operating hole at the middle of the upper and lower arc edges. The bottom plate of the tank has a bottom plate positioning groove for installing the bottommost tank wall module unit.

2. The modular prestressed storage tank according to claim 1, characterized in that, It also includes horizontal connecting steel strands, horizontal prestressed steel strands, vertical connecting steel strands and vertical prestressed steel strands, all of which are anchored at both ends, for applying prestress to the steel strands; The operating hole is provided with horizontal module connection channels, horizontal prestressing channels, vertical module connection channels, and vertical prestressing channels for connecting multiple tank wall module units. The horizontal connecting steel strands are threaded through the horizontal module connecting channels, the horizontal prestressed steel strands are threaded through the horizontal prestressing channels, the vertical connecting steel strands are threaded through the vertical module connecting channels, and the vertical prestressed steel strands are threaded through the vertical prestressing channels.

3. The modular prestressed storage tank according to claim 2, characterized in that, The joints between the tank wall module units and the connection area between the tank wall module unit and the bottom plate of the tank are filled with ultra-high performance concrete.

4. The modular prestressed storage tank according to claim 3, characterized in that, The bottom plate positioning groove is connected to the horizontal connection area of ​​the tank wall module unit.

5. An installation method for a modular prestressed storage tank, comprising the modular prestressed storage tank as described in any one of claims 1-4, characterized in that, It also includes the following steps: 1) Prefabricate tank wall modules in the factory, cure them to the design strength, and then transport them to the construction site; 2) After the anchors and initial steel strands are installed at the construction site, concrete is poured to form the bottom plate of the tank. After the bottom plate of the tank has been cured to the design strength, preparations for hoisting are made. 3) Use a crane to hoist the first layer of tank wall module unit into place, and temporarily fix it by aligning its bottom with the positioning groove of the bottom plate of the tank bottom plate; 4) Insert the horizontal connecting steel strands, horizontal prestressed steel strands, vertical connecting steel strands, and vertical prestressed steel strands into the corresponding ducts, install the anchorages, and then tension the steel strands to the predetermined prestress value. 5) Inject ultra-high performance concrete into the horizontal connection area of ​​the first layer tank wall module unit and the annular gap formed by the bottom of the tank wall module unit and the positioning groove of the bottom plate to realize the connection between the tank wall module unit and the bottom plate of the tank. 6) Following the methods in steps 3) to 5), install the subsequent tank wall module units in sequence. After each tank wall module unit is installed, pour ultra-high performance concrete into the horizontal connection area of ​​that tank wall module unit and the vertical connection area between that layer and the next layer until the installation of all tank wall module units is completed.

6. The installation method of the modular prestressed storage tank according to claim 5, characterized in that, In step 1), the factory prefabrication includes: fabrication of inner steel plate units, welding of studs and casting of concrete units, and reserving in the concrete units misalignment positioning areas, operating holes, horizontal module connection channels, horizontal prestressing channels, vertical module connection channels and vertical prestressing channels.

7. The installation method of the modular prestressed storage tank according to claim 5, characterized in that, In step 2), the on-site construction of the tank bottom plate includes: pre-embedding initial vertical connecting steel strands and vertical prestressed steel strands in a certain area of ​​the tank bottom plate.

8. The installation method of the modular prestressed storage tank according to claim 5, characterized in that, In step 3), the temporary fixing is achieved by aligning the structure at the bottom of the tank wall module unit with the bottom plate positioning groove of the tank bottom plate, while the misalignment positioning area is used to assist in positioning and temporary fixing.

9. The installation method of the modular prestressed storage tank according to claim 5, characterized in that, In step 4), the lower ends of the vertical connecting steel strand and the vertical prestressed steel strand are connected to the anchors and steel strands pre-embedded in the bottom plate of the tank.

10. The installation method of the modular prestressed storage tank according to claim 5, characterized in that, In step 5), after the ultra-high performance concrete is poured, the next layer of tank wall module unit can be installed without waiting for curing.

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