Anchor belt plate construction method for annular frame beam of large double-wall storage tank foundation

Abstract

The invention discloses a construction method for an annular frame beam anchor belt plate of a large double-wall storage tank foundation. The bottom face of an anchor belt plate base is fixedly connected with supporting steel bars used for conducting vertical supporting and auxiliary positioning on the anchor belt plate. Measuring and lofting on the beam bottom template, and marking the projection of each anchor belt plate base in the horizontal direction; steel pipe supporting frames are erected on the beam head and the midspan respectively, in-place anchor belt plates and beam stirrups are sequentially installed from the two sides of the beam to the middle position with the position of a cross rod of the midspan steel pipe supporting frame as the boundary, and finally beam anti-torsion steel bars are bound; when the anchor belt plate is mounted, the anchor belt plate is moved to enable the projection of the anchor belt plate to coincide with the projection mark on the beam bottom template for positioning; after the anchor belt plate is installed in the beam steel reinforcement framework, the steel pipe supporting frame is removed, the anchor belt plate synchronously slides down along with the beam steel reinforcement framework, and when supporting steel bars at the bottom of the anchor belt plate base make contact with a beam bottom formwork, the anchor belt plate reaches the designed elevation. The method is high in installation speed and high in efficiency, and installation precision and construction quality are guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of storage tank foundation construction, in particular to a construction method for an annular frame beam anchor plate of a large double-wall storage tank foundation. Background Art

[0002] In recent years, the construction of anchor plates in the foundation of large storage tanks has become increasingly difficult due to the large amount of installation work and high precision requirements. Usually, the embedded parts on the concrete beam are installed on the side or bottom and top surfaces of the beam. The embedded steel plate is flush with the concrete beam surface, and the anchor bars are anchored in the concrete beam. However, in some large double-walled storage tank foundation frames, the anchor plates are suspended in the beam skeleton before the beam concrete is poured, and the beam stirrups and anchor plates cannot pass through each other. The positioning, fixing, and installation of the anchor plates are all difficult. Without the correct installation method, not only will the installation quality be affected, but large-scale rework and idle work may also occur. Therefore, the development of an efficient anchor plate installation method is of great significance to the construction quality and progress of large storage tanks. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a construction method for anchor strip plates of annular frame beams of a large double-wall storage tank foundation, so as to improve the efficiency and quality of the installation of the anchor strip plates.

[0004] To solve the above technical problems, the present invention provides a method for constructing an anchor plate for a ring frame beam of a large double-walled storage tank foundation. The anchor plate comprises a base and a plate strip, the plate strip being fixed to the top of the base, and the bottom surface of the base being fixedly connected to support steel bars for vertical support and auxiliary positioning of the anchor plate. The construction steps include: Step 1: Measure and set out on the beam bottom template, marking the horizontal projection of each anchor plate base; Step 2: Set up steel pipe support frames at the beam head and mid-span as temporary support and fixing systems for the anchor plate and beam reinforcement skeleton; Step 3: Using the mid-span steel pipe support frame crossbar as the boundary, install the anchor plates and beam stirrups in sequence from both sides of the beam to the middle, and finally tie the beam torsional reinforcement. When installing the anchor plates, position them by moving them so that their projections coincide with the projection marks on the beam bottom template. Step 4: After the anchor plate is installed in the beam reinforcement frame, the steel pipe support frame is removed, and the anchor plate slides down synchronously with the beam reinforcement frame. When the support steel bar at the bottom of the anchor plate base contacts the beam bottom formwork, the anchor plate reaches the design elevation; Step 5: Align and accurately position the anchor strip, and check the position and elevation of the embedded anchor strip; Step 6: Pour frame concrete.

[0005] As a preferred embodiment, the anchor strip plate includes a stiffening plate fixed to the upper surface of the base and connected to the side surface of the plate strip.

[0006] As a preferred embodiment, the anchor strip plate includes an inner anchor strip plate and an outer anchor strip plate, and the inner and outer anchor strip plates are respectively arranged in the outermost ring beam of the frame.

[0007] As a preferred embodiment, in step one, a total station is first set up at the center of the tank foundation frame, and the inner and outer circular axes where the centers of the inner and outer anchor plates are located are measured and placed on the outermost ring beam bottom template.

[0008] As a preferred embodiment, in step 2, the steel pipe support frame is set up at a position away from the anchor plate installation position, and each steel pipe support frame includes two side vertical poles and upper and lower horizontal poles.

[0009] As a preferred embodiment, in step three, the upper and lower horizontal bars respectively support the upper and lower longitudinal bars of the beam, and after being supported, the upper and lower longitudinal bars of the beam are 500 mm higher than the bottom formwork of the beam.

[0010] As a preferred embodiment, in step four, the lower cross bar of the support frame is first removed, and then the connecting fasteners of the upper cross bar are loosened, and the anchor plate slides down synchronously with the beam reinforcement skeleton.

[0011] As a preferred embodiment, in step five, use a steel ruler to check the distance between two adjacent anchor plates, and use a crowbar to pry the steel frame to fine-tune the anchor plates so that the center line position deviation of the anchor plates is controlled within 5 mm; by adjusting the verticality and adding pads at the bottom of the supporting steel bars, ensure that the horizontal height difference of the anchor plates is controlled within +3.0 mm.

[0012] As a preferred embodiment, in step five, a total station and a level are set up to respectively check the position and elevation of the anchor plate so that the center line position deviation is controlled within 5 mm and the horizontal height difference is controlled within +3.0 mm.

[0013] As a preferred embodiment, in step six, the elevation and verticality of the anchor plate are rechecked before the initial setting of the concrete.

[0014] The anchor plate installation construction method provided by the present invention has the following technical effects: By measuring and setting out on the beam bottom template, the horizontal projection of the anchor plate base is marked so that the anchor plate can be accurately positioned in a suspended state, ensuring installation accuracy and construction quality.

[0015] A steel pipe support frame is set up as a temporary support and fixing system for the anchor plate and beam reinforcement. The steel frame and anchor plate are installed in an overhead state, ensuring the smooth installation of the anchor plate and the smooth binding of the beam reinforcement.

[0016] Welding supporting steel bars at the bottom of the anchor plate base can vertically fix and assist in positioning the anchor plate.

[0017] Stirrups and anchor plates are constructed in sections from both ends of the beam to the middle, positioned at intervals, and installed in sequence, so that the anchor plates and stirrups are coordinated and installed in sequence, which makes the installation fast, efficient, and saves installation labor.

[0018] The method provided by the present invention can firmly fix the anchor strip plate and avoid the disadvantage of damaging the mechanical properties of the stressed steel bars by welding with the main bars. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings herein are used to provide further illustration of the present invention and constitute a part of this application. The illustrative embodiments of the present invention and their description are used to explain the present invention and do not constitute improper limitations on the present invention.

[0020] Figure 1 This is a schematic diagram of the installation and construction of the anchor plate of the present invention; Figure 2 It is a structural schematic diagram of the anchor plate described in this specification.

[0021] In the figure, 1-anchor plate, 2-base, 3-plate strip, 4-stiffening plate, 5-support steel bar, 6-beam bottom formwork, 7-steel pipe support frame, 8-beam stirrups, 9-beam torsional steel bar, 10-beam longitudinal reinforcement, 11-steel pipe frame under beam bottom formwork, 12-plate bottom formwork. DETAILED DESCRIPTION

[0022] In order to make those skilled in the art better understand the present invention, the present invention is further clearly and completely described below in conjunction with the accompanying drawings and embodiments. It should be noted that, unless there is a conflict, the features in the embodiments and examples of this application can be combined with each other.

[0023] A typical embodiment of the present invention provides a method for constructing an anchor plate of a ring frame beam of a large double-walled storage tank foundation, wherein the anchor plate 1 includes a base 2 and a plate strip 3, the plate strip 3 is fixed to the top of the base 2, the plate strip 3 passes through the base 2 and is exposed 20 mm on the bottom surface of the base, and the bottom surface of the base 2 is fixedly connected to a supporting steel bar 5 for vertically supporting and assisting in positioning the anchor plate 1.

[0024] Before the concrete is poured into the beam, the anchor plate 1 is suspended within the beam reinforcement framework, with the anchor plate base 2 and plate strip 3 parallel and perpendicular to the beam bottom formwork 6, respectively. By adding support bars 5 to the bottom of the anchor plate base 2 to secure the anchor plate 1 vertically, and combining them with beam stirrups 8 on both sides to secure the anchor plate 1 horizontally, this method is not only simple and easy to implement, but also avoids the drawback of conventional construction where welding to the main bars affects the mechanical properties of the main bars.

[0025] The projections of the anchor plate bases 2 in the horizontal direction are marked on the beam bottom template 6 by measuring and setting out. The problem of difficulty in positioning the anchor plate due to its suspended state is solved by overlapping the projection surfaces.

[0026] Steel pipe support frames 7 are erected at the beam head and mid-span to serve as a temporary support and anchoring system for the anchor plates and beam reinforcement. Using the crossbar position of the mid-span steel pipe support frame 7 as the boundary, the anchor plates 1 and beam stirrups 8 are installed sequentially from both sides of the beam toward the center. Finally, the beam torsional reinforcement 9 is tied. When installing the anchor plates 1, they are positioned by moving them so that their projection aligns with the projection mark on the beam bottom formwork 6.

[0027] This collaborative, directionally, sequentially, and spaced installation method avoids the wasteful rework that occurs during conventional construction, when the anchor strips and stirrups cannot intersect. The overhead lashing of beam reinforcement, with torsional reinforcement reserved and beam side formwork installed last, not only ensures smooth installation of the anchor strips within the beam framework but also ensures effective lashing at the vertical and horizontal intersections of the beam reinforcement.

[0028] After the anchor plate 1 is installed within the beam reinforcement framework, the steel pipe support frame 7 is removed, and the anchor plate 1 is lowered synchronously with the beam reinforcement framework. When the support bars 5 at the bottom of the anchor plate base 2 contact the beam bottom formwork 6, the anchor plate 1 reaches the designed elevation. The anchor plate 1 is then aligned and precisely positioned, and the position and elevation of the pre-embedded anchor plate are verified before the frame concrete is poured.

[0029] A relatively specific embodiment is provided below to further clearly and completely illustrate the technical solution claimed in the present invention.

[0030] In this embodiment, the anchor plate 1 within the outermost ring beam of the liquid ammonia storage tank foundation frame serves as an embedded component. Compared to conventional embedded components, it has the following features: 1. The anchor plate 1 is welded together from a plate strip 3, a base 2, and two stiffening plates 4. 2. With the exception of a portion of the plate strip 3 exposed at the top of the beam, the remaining plate strip 3, base 2, and stiffening plates 4 are anchored within the concrete beam, with the base 2 positioned 340 mm from the beam bottom. 3. The beam is densely reinforced, with a cross-section of 1350 × 1100 mm and equipped with 43 longitudinal bars 10 (Ø28 steel bars), 10 torsional bars 9 (Ø16 steel bars), and 12 stirrups 8 (Ø12 steel bars). The stirrups 8 are spaced 100-200 mm apart.

[0031] The above structural features cause the following difficulties in construction: 1. The installation of embedded parts usually involves tying the beam reinforcement first, and then installing the embedded parts. The anchor plate in this embodiment is a type of embedded part. If constructed according to conventional methods, after tying the beam reinforcement, the anchor plate 1 cannot be installed into the beam skeleton because the spacing between the beam reinforcements is too small; if the anchor plate 1 is installed first and then the beam reinforcement is installed, the anchor plate 1 is in a suspended state and cannot be effectively fixed. 2. During construction, the anchor plate 1 is in a suspended state in the beam reinforcement skeleton. It is difficult to accurately position the anchor plate when installing it between dense ring beam reinforcements, which affects the installation quality and accuracy of the anchor plate. 3. The anchor plate 1 is suspended in the beam reinforcement skeleton and is difficult to fix securely during construction. The conventional fixing method of welding with the structural reinforcement is likely to damage the mechanical properties of the structural stress-bearing reinforcement, affecting the quality of the project. 4. In order to tie the beam reinforcement, the steel pipe support frame 7 is needed to stand up and tie the beam reinforcement. Because the positions of the cross tubes and anchor plates of the steel pipe support frame 7 are fixed, and the number of beam stirrups 8 is large, the beam stirrups 8 cannot pass through the cross bars of the steel pipe support frame and the anchor plates in place within the beam section. If the installation sequence of the beam stirrups 8 and the anchor plates 1 is wrong during construction, and the stirrups in each beam section are incorrectly distributed, it will cause installation conflicts among the steel bars, steel pipe support frame 7, and anchor plates 1. It is necessary to remove some beam stirrups 8 or anchor plates 1 and reinstall them, which is not only time-consuming and labor-intensive but also affects the construction quality.

[0032] The anchor plate construction method provided in this embodiment mainly includes: (1) pre-embedded anchor plate 1 production and welding supporting steel bars 5 to the anchor plate base 2; (2) pre-embedded anchor plate 1 positioning and elevation control; (3) setting up steel pipe support frames 7 at the beam head and mid-span respectively; (4) pre-embedded anchor plate 1 installation; (5) pre-embedded anchor plate 1 alignment and precise positioning; (6) checking the position and elevation of the pre-embedded anchor plate 1; and (7) pouring frame concrete.

[0033] Fabrication of pre-buried anchor strips and welding of supporting steel bars at the base of the anchor strips The anchor plate 1 described in this embodiment includes an inner anchor plate and an outer anchor plate, and the anchor plate includes a base 2, a stiffening plate 4 and a plate belt 3.

[0034] The length, width, and thickness of the inner anchor plate 3 are: 1770×180×18mm. The length, width, and thickness of the outer anchor plate 3 are: 1010×180×18mm. The length, width, and thickness of the base 2 are: -340×170×40mm, and the length, width, and thickness of the stiffener 4 are: -100×75×12mm. Two anchor plates are provided for each tank. The tank foundation is a frame-type foundation, with inner and outer anchor plates arranged within the outermost ring beam of the frame. There are 80 outer anchor plates, evenly distributed along the 35.4m diameter, and 80 inner anchor plates, evenly distributed along the 33.6m diameter.

[0035] A 340mm long Ф25 support steel bar 5 is welded to the bottom surface of the anchor plate base 2. On the one hand, the support steel bar 5 can provide vertical support to the anchor plate 1; on the other hand, the support steel bar 5 serves as a fixed-length steel bar to assist in positioning to control the elevation of the anchor plate 1. After the installation of the anchor plate 1 is completed, when the bottom of the support steel bar 5 is supported on the beam bottom formwork 6, the elevation of the anchor plate 1 is the design elevation.

[0036] Embedded anchor plate positioning and elevation control In this embodiment, a total of 160 pre-buried anchor plates 1 are distributed on the outer ring beam of the liquid ammonia storage tank foundation frame, 80 outer anchor plates are evenly distributed on the outer circle of the ring beam with a diameter of 35.4m, and 80 inner anchor plates are evenly distributed on the inner circle of the ring beam with a diameter of 33.6m. A total station is used to locate the axis and center of the anchor plate, and the elevation of the anchor plate 1 is controlled by the supporting steel bars 5 welded to the bottom of the base 2.

[0037] First, set up a total station on the center of the plate bottom formwork 12, measure and place the inner and outer circular axes where the centers of the inner and outer anchor plates are located on the outermost ring beam bottom formwork, measure and place the center position of the horizontal projection of each inner and outer anchor plate, and mark the specific position of the horizontal projection of the anchor plate 1 on the beam bottom formwork 6.

[0038] Set up steel pipe support frames at the beam head and mid-span The steel pipe support frame 7 is erected at a position away from the installation position of the anchor plate 1. Each steel pipe support frame 7 includes two side vertical poles and two upper and lower horizontal poles. The steel pipe support frame 7 is erected using a Ф48.3×3.6mm fastener-type steel pipe.

[0039] Embedded anchor plate installation The upper and lower horizontal bars respectively support the upper and lower longitudinal reinforcements 10 of the beam. After the upper and lower longitudinal reinforcements 10 of the beam are supported, they are 500 mm higher than the beam bottom formwork 6.

[0040] According to the projection position pre-marked on the beam bottom template 6, the anchor plate 1 is manually installed using an infrared level. Since the minimum spacing between the beam stirrups 8 is 100 mm, if the steel bars are tied first, the anchor strip cannot be constructed. Therefore, the construction of the anchor plate 1 requires close cooperation between the steel bars and the embedded parts installation. The installation adopts the beam stirrups 8 and the anchor plate 1 to be constructed in sections from both ends of the beam to the middle, and installed at intervals and in sequence.

[0041] Specifically, with the crossbar position of the mid-span steel pipe support frame as the boundary, the anchor plate 1 and the beam stirrups 8 are installed in sequence from both sides of the beam to the middle position, and finally the beam torsional reinforcement 9 is tied; when installing the anchor plate 1, the anchor plate 1 is positioned by moving it so that the projection of the anchor plate 1 coincides with the projection mark on the beam bottom template 6.

[0042] After the anchor plate 1 and beam reinforcement skeleton are installed and tied, the lower crossbar of the steel pipe support frame is removed. The connecting fasteners at both ends of the upper crossbar are loosened to put the beam reinforcement skeleton in place. The anchor plate 1 then slides down synchronously with the beam reinforcement skeleton. When the support bars 5 welded at the bottom of the base 2 contact the beam bottom formwork 6, the anchor plate 1 has been installed to the design elevation. Then, the upper crossbar of the steel pipe support frame 7 is removed.

[0043] Alignment and precise positioning of embedded anchor strips Use a steel ruler to check the distance between two adjacent anchor plates, and use a crowbar to pry the steel frame to fine-tune the anchor plate so that the center line position deviation of the anchor plate is controlled within 5mm; by adjusting the verticality and adding pads at the bottom of the supporting steel bar 5, ensure that the horizontal height difference of the anchor plate installation is controlled within +3,0mm, that is, between 3mm-0mm.

[0044] Review the position and elevation of the embedded anchor strip Set up a total station and a level to check the position and elevation of the anchor plate so that the center line position deviation is controlled within 5mm and the horizontal height difference is controlled within +3,0mm, that is, between 3mm-0mm.

[0045] Pouring frame concrete Before pouring concrete for frame columns, beams and slabs, the center line, elevation and verticality of the anchor plate 1 shall be reviewed to ensure that the center line position of the anchor plate 1 is correct and the stability of the anchor plate 1 is guaranteed; after they are accurate, the foundation concrete can be poured, and the elevation and verticality of the anchor plate 1 shall be rechecked before the initial setting of the concrete to ensure the construction quality of the embedded anchor plate 1.

[0046] The scope of protection claimed by the present invention is not limited to the above specific embodiments. For those skilled in the art, the present invention may have various variations and modifications. Any modifications, improvements and equivalent substitutions made within the concept and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for constructing annular frame beam anchor strip plates for a large double-walled storage tank foundation, characterized in that: The anchor plate includes a base and a plate strip, the plate strip is fixed to the top of the base, and the bottom surface of the base is fixedly connected to support steel bars for vertical support and auxiliary positioning of the anchor plate; The construction steps include: Step 1: Measure and set out on the beam bottom template, marking the horizontal projection of each anchor plate base; Step 2: Set up steel pipe support frames at the beam head and mid-span as temporary support and fixing systems for the anchor plate and beam reinforcement skeleton; Step 3: Using the mid-span steel pipe support frame crossbar as the boundary, install the anchor plates and beam stirrups in sequence from both sides of the beam to the middle, and finally tie the beam torsional reinforcement. When installing the anchor plates, position them by moving them so that their projections coincide with the projection marks on the beam bottom template. Step 4: After the anchor plate is installed in the beam reinforcement frame, the steel pipe support frame is removed, and the anchor plate slides down synchronously with the beam reinforcement frame. When the support steel bar at the bottom of the anchor plate base contacts the beam bottom formwork, the anchor plate reaches the design elevation; Step 5: Align and accurately position the anchor strip, and check the position and elevation of the embedded anchor strip; Step 6: Pour frame concrete.

2. The method according to claim 1, wherein: The anchor strip plate includes a stiffening plate fixed to the upper surface of the base and connected to the side surface of the plate strip.

3. The method according to claim 1 or 2, characterized in that: The anchor strip plate comprises an inner anchor strip plate and an outer anchor strip plate, and the inner and outer anchor strip plates are respectively arranged in the outermost ring beam of the frame.

4. The method according to claim 3, wherein: In step one, first set up a total station at the center of the tank foundation frame, and measure and place the inner and outer circular axes where the centers of the inner and outer anchor plates are located on the outermost ring beam bottom template.

5. The method according to claim 1 or 4, characterized in that: In step 2, the steel pipe support frame is set up at a position that avoids the installation position of the anchor plate. Each steel pipe support frame includes vertical poles on both sides and upper and lower horizontal poles.

6. The method according to claim 5, characterized in that: In step three, the upper and lower horizontal bars respectively support the upper and lower longitudinal reinforcements of the beam. After being supported, the upper and lower longitudinal reinforcements of the beam are 500mm higher than the bottom formwork of the beam.

7. The method according to claim 6, characterized in that: In step 4, first remove the lower cross bar of the support frame, then loosen the connecting fasteners of the upper cross bar, and the anchor plate will slide down synchronously with the beam reinforcement skeleton.

8. The method according to claim 1 or 7, characterized in that: In step five, use a steel ruler to check the distance between two adjacent anchor plates, and use a crowbar to pry the steel frame to fine-tune the anchor plates so that the center line position deviation of the anchor plates is controlled within 5mm; by adjusting the verticality and adding pads at the bottom of the supporting steel bars, ensure that the horizontal height difference of the anchor plates is controlled within +3.0mm.

9. The method according to claim 8, characterized in that: In step five, set up a total station and a level to check the position and elevation of the anchor plate, so that the center line position deviation is controlled within 5mm and the horizontal height difference is controlled within +3.0mm.

10. The method according to claim 1, wherein: In step six, the elevation and verticality of the anchor plate are rechecked before the concrete begins to set.

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