LNG (Liquefied Natural Gas) storage tank double-bearing platform with rigid annular plate structure

Abstract

The utility model provides an LNG (Liquefied Natural Gas) storage tank double bearing platform with a rigid annular plate structure. The LNG storage tank double bearing platform comprises a pile foundation, a lower bearing platform, an empty space short column, an upper bearing platform and an LNG storage tank, the bottom of the lower bearing platform is a construction starting working face, the multiple pile foundations are evenly arranged below the lower bearing platform, the upper bearing platform and the lower bearing platform are connected through the multiple empty space short columns, and the LNG storage tank is arranged on the upper bearing platform. A rigid annular plate structure is arranged at the joint of the lower bearing platform and the pile foundation, and a shock insulation support is arranged at the joint of the empty space short column and the upper bearing platform. The lower bearing platform has the advantages that the lower bearing platform and the pile foundation are organically connected through the arrangement of the pre-buried rigid annular plate, the horizontal bearing capacity of the pile foundation is improved, meanwhile, construction steps are optimized, and great economic benefits can be brought to engineering.

Description

Technical Field

[0001] The utility model belongs to the technical field of industrial building petrochemical industry, and particularly relates to a double bearing platform of an LNG storage tank with a rigid ring plate structure. Background Art

[0002] In order to solve the seismic design problem of cryogenic storage tanks in high-intensity earthquake areas under SSE (Safe Shutdown Earthquake) and OBE (Operating-Basis Earthquake) conditions, a seismic isolation pad is used to connect the short column top of the cryogenic storage tank and the upper cap. Due to the low temperature nature of the cryogenic storage tank, the foundation of the cryogenic storage tank adopts a high pile cap overhead design scheme to timely evacuate the lower temperature of the tank outside the tank to prevent the frost heave hazard of the foundation soil. Since the high pile cap scheme with seismic isolation leads to the pile group coefficient value being too small, resulting in too low horizontal bearing capacity of the pile foundation, a rigidly connected double raft (upper cap + lower cap) structural design scheme is adopted to strengthen the interaction between the cap and the soil, improve the horizontal bearing capacity of the pile foundation, and speed up the construction speed. In the engineering field, double raft cryogenic storage tanks with seismic isolation pads are already a mainstream trend, but compared with the previous single raft high pile cap scheme, the double raft scheme greatly extends the entire tank construction period. Therefore, it is necessary to design a connection node and structure between the low-temperature storage tank pile group and the lower pedestal rigid ring plate with seismic isolation pads, which not only ensures the seismic performance of the low-temperature storage tank foundation, but also greatly shortens the tank construction period and takes into account economic benefits. Utility Model Content

[0003] In view of this, the utility model aims to propose a double pedestal for an LNG storage tank with a rigid ring plate structure. The double raft foundation scheme of the lower pedestal with a ring plate rigid connection node can not only meet the larger horizontal bearing capacity requirements of the pile foundation, but also solve the efficiency problem caused by the tight construction period caused by the double raft foundation.

[0004] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0005] A double cap for an LNG storage tank with a rigid ring plate structure, comprising a pile foundation, a lower cap, an overhead short column, an upper cap, and an LNG storage tank;

[0006] The bottom of the lower cap is the construction work surface, and a number of pile foundations are evenly arranged below the lower cap. The upper cap is connected to the lower cap by a number of overhead short columns, and the LNG storage tank is arranged on the upper cap.

[0007] A rigid ring plate structure is provided at the connection between the lower pedestal and the pile foundation, and a seismic isolation bearing is provided at the connection between the short column of the overhead layer and the upper pedestal.

[0008] Furthermore, the rigid ring plate structure includes a ring anchor plate, a stiffening rib plate, and a riveted assembly. The ring anchor plate is divided into four pieces and spliced ​​with equal strength to form the main body of the connection node between the lower cap and the pile foundation;

[0009] The stiffening rib plate is arranged on the outside of the annular anchor plate, the stiffening rib plate is located in the middle of the annular anchor plate, the stiffening rib plate is fixedly connected to the annular anchor plate, and preferably, a full penetration equal strength weld is adopted with the annular anchor plate;

[0010] A plurality of riveting assemblies are arranged on the inner side of the annular anchor plate;

[0011] Furthermore, the riveting assembly includes an anchoring steel bar, an end plate, and a nut; one end of the anchoring steel bar is fixedly connected to the annular anchor plate, and the other end is anchored in the pile foundation through the nut and the end plate.

[0012] One end of the anchor steel bar is plug welded to the hole of the annular anchor plate, and the other end is fixed to the end plate by a nut and anchored in the pile.

[0013] Furthermore, the anchoring steel bars and annular anchor plates are pre-tied to the last section of the steel cage of the pile foundation, and measures are taken to ensure that the rigid annular plate structure is accurately positioned along the length direction of the pile foundation to avoid the influence of the "floating cage"; the outer side of the pile foundation of the LNG storage tank is provided with an outer ring spiral stirrup, and the inner side of the pile foundation of the LNG storage tank is provided with an inner ring positioning spiral steel bar.

[0014] And / or, cushion layers are provided on both upper and lower sides of the lower cap; a plurality of lower cap transverse and longitudinal force-bearing steel bars are provided in the lower cap;

[0015] And / or, the seismic isolation bearing includes one or two or more of a lead rubber seismic isolation bearing, a high damping seismic isolation bearing or a friction seismic isolation bearing. Preferably, the seismic isolation bearing is a lead rubber seismic isolation pad.

[0016] Furthermore, the distance between the upper platform and the foundation is at least 1.8m;

[0017] And / or, the material of the annular anchor plate and the stiffening rib plate is one or both of Q355B and Q235B.

[0018] The utility model provides a method for preparing a double support platform of an LNG storage tank with a rigid ring plate structure, comprising the following steps:

[0019] The bottom of the lower pedestal is the starting working surface of the construction. The foundation reinforcement treatment is carried out on the starting surface of the construction. Then, the pile foundation and the overhead short column are integrated. Before the overhead short column is molded, the number of single-row anchor bars of the rigid ring plate connection node and the number of vertical rows are selected, and their strength is verified. If they do not meet the verification requirements, the number and the number of rows are adjusted until they meet the verification requirements. Then, the rigid ring plate structure anchor bars and the rigid ring plate are pre-tied to the last section of the steel cage of the pile foundation. After the steel cage is tied, the pile foundation concrete is poured. After the integrated construction of the pile foundation and the overhead short column is completed, the size of the stiffening rib plate that meets the strength is selected and welded to the middle of the annular anchor plate through full penetration and equal strength welds. Then, the seismic isolation bearings are arranged on the overhead short column, and then the upper pedestal is constructed. After the construction of the upper pedestal is completed, the outer tank wall and the lower pedestal are constructed in parallel. The force-bearing steel bars of the lower pedestal are welded to the stiffening rib plate, and the construction is completed.

[0020] Furthermore, the foundation is a pile group foundation, the pile foundation is a cast-in-place pile, and the working surface of the pile group foundation is the bottom elevation of the lower cap;

[0021] Furthermore, the strength of the rigid ring plate connection structure is verified, and the failure forms of the rigid ring plate connection structure include one or more of the rigid ring plate failure, anchor steel bar pull-out failure, and concrete crushing failure at the anchor plate;

[0022] The number of horizontal single-row anchor steel bars n along the annular direction ranges from 3 to 9, the number of vertical rows of anchor steel bars p ranges from 2 to 3 rows, and the anchor steel bars are HRB400E steel bars.

[0023] Considering the shear structure, the diameter d of the anchor steel bar a Not less than the diameter of the horizontal and vertical force-bearing steel bars of the lower cap Preferably, the diameter d of the anchor steel bar a 12mm~25mm; the minimum length of anchor steel bar is not less than 12d a , preferably, the length of the anchor steel bar ranges from 250 mm to 300 mm;

[0024] Vertical annular spacing of anchor bars ≥ 8d a Preferably, the vertical circumferential spacing of the riveted assembly is 180 mm to 250 mm; more preferably, the anchor steel bar and the circumferential anchor plate are welded by perforation plug welding.

[0025] This application uses a finite element model to calculate the cross-sectional bending moment, axial force and shear force at the connection between the lower cap and the pile, and selects the most unfavorable load by load combination, thereby obtaining the steel bar model and spacing for the lower cap, and then obtaining the design value N of the strength reinforcement bearing capacity of the lower cap according to the equal strength design principle;

[0026] The calculation of rigid ring plate failure includes: Design value of tensile bearing capacity of anchor reinforcement N 1 Should satisfy the public

[0027] As shown in formula 1 (k is a positive integer):

[0028]

[0029] n is the number of horizontal single-row anchor bars in the annular direction;

[0030] N is the design value of the strength reinforcement bearing capacity of the lower cap, N;

[0031] p is the number of vertical rows of anchor bars;

[0032] The diameter of the anchor steel bar is d a The specific calculation process is shown in Formula 2:

[0033]

[0034] N 1 The design value of the tensile bearing capacity of the anchor steel bar connection steel bar, in N;

[0035] f u is the tensile strength of anchor steel bars, N / mm 2 .

[0036] The size of the annular anchor plate is selected, the outer edge of the rigid annular plate is flush with the outer edge of the foundation pile, the thickness t of the annular anchor plate shall not be less than half the diameter of the anchor steel bar, preferably, the thickness t of the annular anchor plate is 16mm to 30mm; the height h of the annular anchor plate is 150 to 250mm;

[0037] Among them, the cross-sectional area of ​​the annular anchor plate is A s As shown in formula (3):

[0038] A s =h·t (3);

[0039] A s is the cross-sectional area of ​​the annular anchor plate, mm 2 ;

[0040] h is the height of the annular anchor plate, mm;

[0041] t is the thickness of the annular anchor plate, mm;

[0042] And the design value of the tensile bearing capacity of the annular anchor plate is N Sa Must satisfy formula (4):

[0043]

[0044] A s is the cross-sectional area of ​​the annular anchor plate, mm 2 ;

[0045] NSa is the design value of the tensile bearing capacity of the annular anchor plate, N;

[0046] f u is the tensile strength of the anchor steel bar, N / mm;

[0047] N is the design value of the strength reinforcement bearing capacity of the lower cap, N;

[0048] Calculation of anchor reinforcement pull-out failure: N b The design value of the tensile bearing capacity when a single anchor steel bar is pulled out must satisfy the formula (5):

[0049]

[0050] N b is the design value of the tensile bearing capacity when a single anchor reinforcement fails, N;

[0051] f cu,k is the standard value of compressive strength of concrete cube in foundation, N / mm 2 ;

[0052] h ef is the anchorage length of the anchor steel bar, mm;

[0053] Verification of concrete crushing failure at the annular anchor plate: The design value of the tensile bearing capacity when concrete crushing failure occurs at the end of a single annular anchor plate must satisfy the formula (6):

[0054] N Pn ≤6.58×A brg ·f cu,k (6);

[0055] N Pn A is the design value of the tensile bearing capacity when concrete crushing failure occurs at the end of a single annular anchor plate, N; brg = The area of ​​the annular anchor plate minus the cross-sectional area of ​​the anchor steel bar (mm) 2 ;

[0056] f cu,k is the standard value of compressive strength of concrete cube in foundation, N / mm 2 ;

[0057] This application adopts equal strength design, that is, the tensile force of the transverse and longitudinal steel bars of the lower cap is all borne by the rigid ring plate to meet the design requirements. At the same time, in order to ensure the safety of the connection node, this utility model requires that the equal strength destruction of the anchor bar simultaneously meets the tensile force of the transverse and longitudinal steel bars of the lower cap, which is used as a safety redundancy. Considering the influence of earthquake action, the anchor bar bearing capacity N 1 Formula (7) must be satisfied;

[0058]

[0059] N 1 The design value of the tensile bearing capacity of the anchor steel bar connection steel bar, in N;

[0060] N Sa is the design value of the tensile bearing capacity of the annular anchor plate, N;

[0061] N b is the design value of the tensile bearing capacity when a single anchor reinforcement fails, N;

[0062] N Pn is the design value of the tensile bearing capacity when concrete crushing failure occurs at the end of a single anchor plate, N;

[0063] n is the number of horizontal single-row anchor bars along the annular direction of the rigid ring plate;

[0064] p is the number of vertical rows of anchor bars; further, the annular anchor plate of the rigid ring plate connection node is spliced ​​into four pieces, and strong connections such as slit welding are used between the rigid ring plates; the cement slurry on the surface of the rigid ring plate structure is removed; the thickness of the lower cap can be adjusted to a variable thickness section according to the internal force results, in which the thickness of the lower cap within the outer three circles of piles is large, and the thickness of the lower cap in the inner circle orthogonal area is small.

[0065] Furthermore, the rigid ring plate connection node adjusts the node size according to the variable cross-section thickness of the lower pedestal.

[0066] Furthermore, the stiffening rib plate is located in the middle of the annular anchor plate, and a full penetration equal strength weld is used with the annular anchor plate; the width of the stiffening rib plate is 100 mm to 150 mm, and the thickness t' of the stiffening rib plate shall not be less than half the diameter of the anchor steel bar. The thickness t' of the stiffening rib plate is recommended to be 12 mm to 16 mm, which is specifically determined by formula (8);

[0067]

[0068] t' is the thickness of the stiffening rib, mm;

[0069] A' s For the same force direction, the total area of ​​welded steel bars on the stiffening rib plate, mm 2 ;

[0070] f u钢筋 is the tensile strength of the steel bar, kN / mm 2 ;

[0071] f u加劲肋 is the tensile strength of the stiffening rib, kN / mm 2 ;

[0072] l a is the length of welded steel bars of the stiffening rib plate, mm.

[0073] Furthermore, the welded annular stiffening ribs on the rigid ring plate connection nodes are welded on site with the upper and lower steel mesh sheets of the lower pedestal. The length of the weld is 10d for single-sided welding and 5d for double-sided welding.

[0074] d represents the diameter of the steel bar, mm;

[0075] Preferably, the connection between the pile foundation and the lower cap is sealed with sealing paste or injected with non-shrinkage grouting material.

[0076] By using the node of the utility model, it can be ensured that the pile group and the short column are constructed in an integrated manner; the top of the short column and the upper pedestal are provided with seismic isolation pad supports; the construction sequence from front to back is optimized from the original "pile group construction-lower pedestal construction-short column construction-upper pedestal construction-external tank construction" to "pile-column integrated construction-upper pedestal construction-external tank wall and lower pedestal parallel construction". It is worth noting that the stress design value of the reinforcement of the pile group foundation adopts the internal force envelope value of the single raft high pile and the double raft pedestal pile foundation. The use of this technical utility model is expected to save 45 to 60 days in the construction period of the cryogenic storage tank.

[0077] Compared with the prior art, the double support platform of the LNG storage tank with a rigid ring plate structure described in the utility model has the following advantages:

[0078] (1) A double cap for LNG storage tanks with a rigid ring plate structure, which adopts integrated construction in the lower piles and short columns and the middle connection area to enhance the integrity of the pile foundation and short columns;

[0079] (2) The present application organically combines the transverse and longitudinal force-bearing steel bars of the lower pedestal with the rigid ring plate by setting a pre-embedded rigid ring plate, which not only ensures the effectiveness of the lower pedestal in bearing the bending moment, but also optimizes the construction steps, which can bring great economic benefits to the project;

[0080] (3) The double-cap structure of the LNG storage tank with a rigid ring plate structure described in the utility model can further optimize the construction steps and shorten the construction period by simultaneously constructing the upper cap and the lower cap after the integrated construction of the pile foundation short column is completed;

[0081] (4) Improve the seismic performance of cryogenic storage tanks. Compared with the single raft high pile cap foundation with vibration isolation pad, the rigidly connected double cap high pile cap foundation with vibration isolation pad can increase the horizontal bearing capacity of the pile foundation by 2.05 times. Strengthen the interaction between the cap and the soil. When the bearing layer at the pile end is uneven, it can effectively resist slippage and ensure the stability of the pile group foundation. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the accompanying drawings:

[0083] Figure 1 This is an overall schematic diagram of a double support platform of an LNG storage tank with a rigid ring plate structure according to an embodiment of the utility model;

[0084] Figure 2 It is a partial schematic diagram of the double support platform of the LNG storage tank with a rigid ring plate structure according to an embodiment of the utility model (the planed line is the interface);

[0085] Figure 3 It is a schematic diagram of the rigid ring plate structure described in an embodiment of the utility model;

[0086] Figure 4 It is a cross-sectional schematic diagram of an LNG storage tank according to an embodiment of the utility model;

[0087] Figure 5 It is a schematic elevation view of the rigid ring plate structure according to an embodiment of the utility model;

[0088] Figure 6 It is a schematic diagram of the annular anchor plate according to an embodiment of the utility model;

[0089] Figure 7 This is a schematic diagram of the structure of the annular anchor plate according to an embodiment of the utility model;

[0090] Figure 8 This is a physical picture of the cast-in-place pile described in the embodiment of the utility model.

[0091] Description of reference numerals:

[0092] 1. Upper pedestal; 2. Isolation bearing; 3. Anchor steel bars; 4. Stiffening ribs; 5. Annular anchor plates; 6. Horizontal and vertical force-bearing steel bars of lower pedestal; 7. Lower pedestal; 8. Cushion; 9. Planing line; 10. Spiral stirrups of the outer ring of pile foundation; 11. Positioning spiral steel bars of the inner ring of pile foundation; 12. End plates; 13. Nuts; 14. Foundation; 15. Short columns of overhead floors; 16. Pile foundation; 17. LNG storage tank. DETAILED DESCRIPTION

[0093] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0094] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0095] In the engineering field, low-temperature storage tanks with double raft systems with seismic isolation have been used, but the pouring and maintenance of double raft concrete greatly prolongs the construction period. Therefore, it is necessary to design a connection structure and structure of double raft cryogenic storage tank piles with seismic isolation pads and the rigid ring plate of the lower cap, which can ensure the seismic performance of the cryogenic storage tank foundation while taking into account the economic benefits.

[0096] The use of a double raft structure on a cryogenic storage tank can strengthen the interaction between the cap and the soil, improve the horizontal bearing capacity of the pile foundation, and improve the seismic performance of the cryogenic storage tank. However, the pouring and maintenance of the double raft concrete greatly increases the construction period. In order to solve the problem that the pouring and maintenance of the double raft concrete greatly increases the construction period, the utility model provides a connection node and structure of a double raft cryogenic storage tank pile group with a seismic isolation pad and a rigid ring plate of a lower cap. This method not only ensures the seismic performance of the cryogenic storage tank foundation, but also takes into account economic benefits.

[0097] like Figure 1 , Figure 2 The figure shows a double support structure of an LNG storage tank with a rigid ring plate structure described in an embodiment of the present utility model.

[0098] like Figure 3 As shown, after the foundation 14 is processed, a double pedestal of an LNG storage tank with a rigid ring plate structure is provided with pile foundation 16 (pile foundation is cast-in-place pile), rigid ring plate connection structure, lower pedestal 7, overhead short column 15, seismic isolation pad support 2, upper pedestal 1 and LNG storage tank supported by upper pedestal 1 in sequence from bottom to top; wherein, the ring plate connection structure is arranged in the intersecting connection area between the lower pedestal 7 and the pile foundation 16, and the ring plate node is composed of anchor steel bars 3, annular anchor plates 5 and stiffening rib plates 4; the pile foundation 16 and the overhead short column 15 are pile-column integrated During construction, seismic isolation pad supports 2 are set on the top of the short column and the upper pedestal; the order of construction from front to back is changed from the original pile foundation 16 construction - lower pedestal 7 construction - overhead short column 15 construction - upper pedestal 1 construction - outer tank construction to the integrated construction of pile foundation 16 overhead short column 15 - upper pedestal 1 construction - outer tank and lower pedestal 7 construction at the same time. At the same time, the horizontal and vertical force-bearing steel bars 6 of the lower pedestal are connected with the stiffening ribs 4 by on-site welding, which not only ensures the effectiveness of the lower pedestal 7 in bearing bending moments, but also optimizes the construction steps, which can bring great economic benefits to the project.

[0099] like Figure 4As shown, the pile foundation 16 adopts the pile-column integrated construction. When the reinforcement cage 10 of the pile group foundation is tied, the annular anchor plate includes 4 rigid annular plates; the rigid annular plates are pre-tied in the reinforcement cage within the range of the lower pedestal 6, and the annular anchor plates of the rigid annular plates are spliced ​​in four pieces, and the rigid annular plates are connected by strong connections such as slit welding; the anchor steel bars 3 of the rigid annular plates are arranged vertically in 2 rows, with an annular spacing of 200mm to 250mm, and the anchor steel bars 3 and the annular anchor plates 5 are connected by perforated plug welding; the other end of the anchor steel bar 3 is connected to the end plate 12, and the connection can be made by nuts 13 or perforated plug welding.

[0100] like Figure 5 , Figure 6 As shown, the rigid ring plate connection node annular anchor plate 5 is provided with horizontal stiffening rib plate 4, which is located in the middle of the annular anchor plate 5 and connected to the annular anchor plate 5 by double-sided fillet welds. At the same time, the annular stiffening rib plate 4 welded on the rigid ring plate connection node is welded to the upper and lower steel mesh of the lower pedestal 7 on site to increase the force-bearing area of ​​the horizontal and vertical force-bearing steel bars 6 of the lower pedestal and the rigid ring plate. The detailed diagram of the rigid ring plate structure is shown in Figure 4 As shown, m is the number of annular anchoring steel bars 3 of the rigid ring plate, and its value is determined by the bending moment and shear force borne by the transverse and longitudinal force-bearing steel bars 6 of the lower pedestal and the short columns 15 of the overhead layer.

[0101] The overall construction process is: first, the pile foundation and the short column are integrated, and then when constructing the overhead short column 15, the upper and lower two sets of annular anchor plates and riveted components are pre-configured at the intersection of the lower pedestal 7 and the pile foundation 16. At this time, the overlapping part of the lower pedestal 7 and the pile foundation 16 is rigidly connected, and the overlapping part of the overhead short column 15 and the lower pedestal 7 and the pile foundation 16 is also rigidly connected; after the integrated construction of the pile foundation 16 and the overhead short column 15 is completed, the seismic isolation bearing 2 is arranged on the overhead short column 15, and then the upper pedestal 1 is constructed. It should be noted that the lower part of the seismic isolation bearing 2 is rigidly connected to the top of the overhead short column 15; after the construction of the upper pedestal 1 is completed, the lower pedestal 7 is constructed; before the construction of the lower pedestal 7, the upper and lower longitudinal force-bearing steel bars are respectively connected to the preset stiffening ribs 4 by welding, and after the steel bars are tied, concrete is poured and maintained, and the foundation construction is completed.

[0102] Embodiment 1:

[0103] The basic information of a low-temperature storage tank is that the tank adopts an upper and lower double-pedestal design. The thickness of the lower pedestal is 1.2m and the pile diameter is 1.5m. The finite element model is used to calculate that the strength reinforcement of the lower pedestal is double-layer bidirectional reinforcement. The top reinforcement and the bottom reinforcement are both X:D25@150, Y:D25@150.

[0104] Select a single rigid ring plate for design and take 1 / 4 of it as the analysis body, then:

[0105] N=5×As25 ×f u =5×491mm 2 ×360N / mm 2 =883.8kN.

[0106] The number of horizontal single-row anchor bars along the ring direction of the rigid ring plate is n=6, and the number of vertical rows of anchor bars is p=2.

[0107] It is known that n is an even number, so N / p≤N 1 ×n, substitute it to get N 1 ≥73.65kN.

[0108] therefore

[0109] At the same time, considering the shear structure, d a ≥2 / 3d=16.67mm, so the anchor bar diameter d is selected a =18mm, update N 1 =146.50kN, anchorage length h ef ≥ 12 days a =216mm, value h ef =250mm.

[0110] Assume that the thickness of the rigid ring plate is t=20 mm, and its height is h=250 mm.

[0111] It can be seen that the cross-sectional area of ​​the annular anchor plate of the rigid ring plate connection node is A s =h×t=250mm×

[0112] 20mm=5000mm 2 .

[0113] It can be seen that the design value of the tensile bearing capacity of the annular anchor plate of the rigid ring plate connection node is

[0114] It can be seen that the assumption that the thickness of the rigid ring plate meets the design requirements is valid.

[0115] Next, the anchor bar pull-out failure verification is carried out. The design value of the tensile bearing capacity when a single anchor bar is pulled out

[0116] In this example, the size of the anchor plate at the end of the anchor bar is 60mm×60mm, so the tensile bearing capacity verification when concrete crushing failure occurs at the end of a single anchor plate is:

[0117] N Pn ≤6.58×A brg ·f cu,k =6.58×60×60×40×10 3=947.52×10 3 kN

[0118]

[0119] Meet design safety requirements.

[0120] In summary, the selected rigid ring plate structures all meet the strength requirements, all the assumed values ​​are valid, and the design requirements are met.

[0121] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A double support platform for LNG storage tanks with a rigid ring plate structure, characterized in that: Including pile foundation, lower pedestal, overhead short column, upper pedestal, and LNG storage tank; Several pile foundations are evenly arranged below the lower cap, the upper cap is connected to the lower cap by several overhead short columns, and the LNG storage tank is arranged on the upper cap; A rigid ring plate structure is provided at the connection between the lower pedestal and the pile foundation, and a seismic isolation bearing is provided at the connection between the short column of the overhead layer and the upper pedestal.

2. The double support platform of an LNG storage tank with a rigid ring plate structure according to claim 1, characterized in that: The rigid ring plate structure includes a ring anchor plate, a stiffening rib plate, and a riveted assembly. The ring anchor plate is divided into four pieces and spliced ​​with equal strength, forming the main body of the connection node between the lower cap and the pile foundation; The stiffening rib plate is arranged on the outside of the annular anchor plate, the stiffening rib plate is located in the middle of the annular anchor plate, and the stiffening rib plate and the annular anchor plate are fixedly connected; A plurality of riveting assemblies are arranged on the inner side of the annular anchor plate.

3. The double support platform of the LNG storage tank with a rigid ring plate structure according to claim 2 is characterized in that: The riveting assembly includes an anchoring steel bar, an end plate, and a nut; one end of the anchoring steel bar is fixedly connected to the annular anchor plate, and the other end is anchored in the pile foundation through the nut and the end plate.

4. The double support platform of the LNG storage tank with a rigid ring plate structure according to claim 3 is characterized in that: The anchoring steel bars and the annular anchor plates are pre-tied to the last steel cage of the pile foundation. The outer side of the pile foundation of the LNG storage tank is provided with an outer ring of spiral stirrups, and the inner side of the pile foundation of the LNG storage tank is provided with an inner ring of positioning spiral steel bars.

5. The double support platform of the LNG storage tank with a rigid ring plate structure according to claim 1, characterized in that: Pad layers are provided on both the upper and lower sides of the lower pedestal; a number of lower pedestal transverse and longitudinal force-bearing steel bars are provided in the lower pedestal.

6. The double support platform of the LNG storage tank with a rigid ring plate structure according to claim 1, characterized in that: The seismic isolation bearing includes one or two or more of a lead rubber seismic isolation bearing, a high damping seismic isolation bearing or a friction seismic isolation bearing.

7. The double support platform of the LNG storage tank with a rigid ring plate structure according to claim 1, characterized in that: The isolation bearing is a lead core rubber isolation pad.

8. The double support platform of an LNG storage tank with a rigid ring plate structure according to claim 1, characterized in that: The distance between the upper platform and the foundation is at least 1.8m.

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