A method for constructing a storage tank using a slip form

Abstract

The application provides a storage tank slip form construction method, and belongs to the technical field of building construction, and comprises the following steps: assembling an attached self-climbing formwork system on the top surface of a foundation, wherein the formwork system comprises independently liftable inner and outer formwork units and a plurality of working platforms; pouring concrete between the inner and outer formwork in layers and testing the lifting, continuously lifting after debugging, synchronously completing the installation of reinforcing steel bars, embedded parts and prestress channels, and the pouring, vibrating, trimming and curing of concrete during the lifting; after lifting to the design elevation, removing the formwork, lowering the formwork and locking, supporting a construction ring beam by the inner formwork unit; after the completion of the ring beam, lowering the outer formwork unit to serve as a prestress tensioning and secondary structure operation platform. The independently liftable inner and outer formwork avoids repeated disassembly, reconstruction, improves the construction efficiency and safety.

Description

Technical Field

[0001] This invention belongs to the field of building construction technology, and more specifically, relates to a slipform construction method for storage tanks. Background Technology

[0002] Slipform construction is a highly efficient continuous casting-in-place concrete forming process widely used in the construction of tall or regular vertical structures such as silos, chimneys, and storage tanks. This technology uses a hydraulic system to drive the formwork and operating platform to continuously slide up the vertical structure, simultaneously completing processes such as rebar tying, concrete pouring, vibration, and surface finishing during the sliding process. It offers advantages such as fast construction speed, good structural integrity, and no construction joints.

[0003] For the construction of tank walls in large storage tanks (especially LNG full-containment tanks), existing slipform technology typically employs a coordinated lifting method for the inner and outer formwork frames. This means the inner and outer formwork frames are raised and lowered synchronously via a unified hydraulic lifting system. The operating platform system is generally arranged circumferentially along the tank wall, and each process must be completed sequentially on the operating platform during the continuous slipforming of the formwork frames.

[0004] However, in existing technologies, because the inner and outer formwork frames work together using a unified lifting system, they cannot independently adjust their height and operating rhythm. Once the tank wall has been raised to the design elevation, if it is necessary to carry out the construction of the tank top ring beam, prestressing tensioning, or secondary structure construction, it is often necessary to completely dismantle or significantly modify the entire slipform frame in order to free up working space. This results in repeated dismantling and reassembly of the formwork frame, extended construction period, and severely restricts construction efficiency. Summary of the Invention

[0005] The purpose of this invention is to provide a slipform construction method for storage tanks, which aims to solve the problems in existing slipform technology where the inner and outer formwork frames work in conjunction, the height cannot be adjusted independently, and the formwork frames need to be repeatedly disassembled and modified after the tank wall is completed, thus restricting construction efficiency.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is: to provide a slipform construction method for storage tanks, comprising the following steps: S1: Assemble an attached self-climbing formwork system on the top surface of the storage tank foundation. The formwork system is divided into an inner formwork unit and an outer formwork unit that can independently perform lifting and lowering actions. The formwork system is equipped with multiple working platforms along the vertical direction. The templates of the inner formwork and the templates of the outer formwork enclose each other to form a tank wall casting chamber. S2: The initial section of concrete is poured in layers in the casting chamber of the tank wall. After the bottom layer of concrete reaches the initial setting state, the formwork system is started for trial lifting. After the debugging and operation are normal, the continuous slip-lift operation is started. S3: The formwork system maintains a uniform and continuous climbing speed. During the slip-lifting process, the steel reinforcement layout, installation of embedded parts and prestressed channels, concrete pouring and vibration, and concrete finishing and curing operations are completed synchronously on the multi-layer working platform. S4: After the tank wall is raised to the design elevation, the template is moved backward to detach from the concrete surface, the formwork system is lowered and locked at the working elevation, and the tank top ring beam structure is constructed with the inner formwork unit as support. S5: After the construction of the tank top ring beam structure is completed, the outer formwork unit is lowered along the track, so that the outer formwork unit serves as an operating platform for prestressing tensioning and secondary structure construction.

[0007] In one possible implementation, in S1, the multi-layer work platform consists of a pre-work layer, a core construction layer, and a repair and maintenance layer from top to bottom. The inner mold frame unit and the outer mold frame unit are respectively equipped with independent drive systems and independent control systems, and the inner mold frame unit and the outer mold frame unit independently perform lifting and lowering actions; The formwork system is equipped with an attachment rail, which is a non-embedded structure. The attachment rail is attached to the concrete wall on one side and undertakes the load-bearing function and climbing guidance function of the formwork system.

[0008] In one possible implementation, in S2, the trial lift operation includes the following steps: S21: After the first layer of concrete is poured, the setting state of the bottom layer of concrete is checked. After the bottom layer of concrete reaches the demolding strength, the formwork system is started and the formwork system is controlled to rise slightly by one stroke height. After the slight rise is completed, the formwork system is stopped. The operating conditions of all power units are inspected one by one to check the sealing status of the hydraulic cylinder, the position of the locking device, and the uniformity of the separation between the formwork and the concrete wall. S22: After the inspection is completed, the mold frame system is controlled to continuously climb to the set test height at a set speed. During the continuous climbing process, the displacement data of each power unit displacement sensor is read in real time through the host computer control system, and the horizontal deviation data of the inner and outer mold frame units is read and recorded. S23: After the formwork system has climbed to the set test height, measure and record the penetration resistance value of the concrete in the formwork, check the appearance quality of the concrete in the formwork and record the flow, collapse and cracking. S24: After measuring the penetration resistance value of the concrete and checking the appearance quality of the concrete, continue to lift the formwork system until the locking device in the slide section is aligned with the set hole on the attachment rail. Stop lifting and lock the slide section to the attachment rail. Retract the main hydraulic cylinder. After the main hydraulic cylinder is retracted, install the load-bearing shoe and lock the load-bearing shoe to the set hole on the attachment rail. Release the locking relationship between the slide section and the attachment rail. Transfer the load-bearing and guiding functions of the formwork system to the load-bearing shoe. After the locking relationship is released, continue the continuous sliding operation.

[0009] In one possible implementation, in S3, the attachment rail is installed in a segmented manner. Before the rail is installed, the inner and outer attachment rails, positioning cones, anchor bars, and joint connecting plates are assembled into a whole on the ground according to the tank wall thickness. After the assembly is completed, a special lifting tool is used to lift the attachment rail as a whole to the installation position. After the attachment rail is lifted to the installation position, the construction personnel stand on the pre-work layer to carry out the joint fixing of the attachment rail.

[0010] In one possible implementation, in S3, the rebar placement operation is completed collaboratively between the preceding work layer and the core construction layer, including: After controlling the spacing and protective layer of the vertical reinforcing bars through the reinforcing bar positioning sleeve on the pre-work layer, the vertical reinforcing bars are extended; on the core construction layer, the spacing lines of the circumferential horizontal reinforcing bars are marked on the vertical reinforcing bars and the circumferential horizontal reinforcing bars are tied according to the spacing lines; hooks are set between the double-layer reinforcing bars on the inner and outer walls; the joints of the vertical reinforcing bars are staggered and the joints of the circumferential horizontal reinforcing bars are staggered.

[0011] In one possible implementation, in S3, the installation of prestressed channels and the placement of reinforcing bars are carried out simultaneously and concurrently, including: Install a positioning template on the formwork system and calibrate its verticality and horizontality; after sealing the front hole of the anchor plate, align the anchor plate with the fixing hole of the positioning template and install it, then fix the anchor plate to the positioning template and the surrounding steel reinforcement skeleton; sleeve a spiral reinforcement on the rear end of the anchor plate and fix the spiral reinforcement to the structural steel reinforcement; connect one end of the flared tube to the anchor plate and the other end of the flared tube to the corrugated pipe, and wrap sealing tape around the joint between the flared tube, the anchor plate, and the corrugated pipe; arrange the corrugated pipe circumferentially and tie it to the positioning reinforcement, leaving an overlap length at the end of the segmented corrugated pipe, and install a sealing cap at the end of the reserved overlap length.

[0012] In one possible implementation, in S3, the concrete pouring adopts a layered symmetrical pouring method, with the pouring height of each layer controlled within a set range. The pouring direction of each layer of concrete is opposite to that of the previous layer. The concrete is pumped into the formwork by a truck pump located in the center of the storage tank. After the concrete is poured into the formwork, it is vibrated with a vibrator. The vibrator is operated in a quick insertion and slow withdrawal manner. When vibrating the upper layer of concrete, the vibrator is inserted into the lower layer of concrete, and the insertion depth is controlled within a set value.

[0013] In one possible implementation, in S3, the finishing and curing operation of the demolded concrete is carried out on the finishing and curing layer. As the mold frame system is raised, the original slurry is rubbed out on the surface of the demolded concrete in sequence using a rubbing board and then smoothed with an iron plate. A spray pipe is arranged in a ring along the inner wall of the tank on the side of the finishing and curing layer near the tank wall. The spray pipe is connected into a closed-loop spray circuit. Spray holes are opened on the spray circuit, and water is sprayed onto the surface of the tank wall concrete through the spray holes for curing.

[0014] In one possible implementation, in S4, the operation of retracting the template away from the concrete surface includes: Remove the connecting bolts at the round holes between the template and the curvature control plate, leaving the connecting bolts at the elongated holes. Move the template and the curvature control plate backward along the guide direction of the elongated holes, causing the template to detach from the concrete surface. After the template detaches from the concrete surface, lower the formwork system until the elevation of the upper surface of the core construction layer is lower than the bottom elevation of the ring beam. Align the locking device pin in the slide section with the bushing hole on the attached track. After the locking device pin is aligned with the bushing hole, insert the locking device pin into the bushing hole to lock it. Remove the inner ring paving plate and the extended section of the skeleton of the outer formwork unit's pre-work layer, leaving the outer ring paving plate. Use the outer ring paving plate as the ring beam construction operation platform and support the bottom formwork of the ring beam on the core construction layer.

[0015] In one possible implementation, a mold frame system dismantling step is included after S5, the mold frame system dismantling including: S101: Remove the construction waste and tools from the four-layer work platform to the ground. The four-layer work platform consists of the pre-work layer, the core construction layer, the repair and maintenance layer, and the painting layer. Temporarily fix the movable paving board. S102: The inner formwork unit and the outer formwork unit are lowered synchronously. During the descent, the fixing bolts of the attachment rails above the core construction layer that have detached from the concrete wall and the positioning cone are removed one by one. The attachment rails are hoisted to the ground in sections and the attachment rails are removed section by section until only the bottom attachment rail remains. S103: Lower the formwork system to the bottom of the repair and maintenance layer, close to the foundation surface, and dismantle the repair and maintenance layer in the order of first removing the guardrail, then removing the paving boards, and finally removing the L-shaped frame. Hoist the dismantled components to the ground. S104: Continue to lower the formwork system, and dismantle the front working layer in the order of first removing the guardrails, then removing the decking, and finally removing the L-shaped frame. Simultaneously remove the operating platform extension and railings corresponding to the front working layer. S105: Starting from the power unit at the control system location, dismantle the core construction layer truss section by section in the order of removing the template, arc control plate, guardrail, railing, operating platform extension, and truss. After dismantling to the slide section position, disconnect the power unit's power line and communication cable, open all locking devices of the power unit, disassemble the power unit in the order of removing the attached track, load-bearing shoe, slide section template, and auxiliary components, and hoist the slide section to the ground. S106: When dismantling the last power unit, use a lifting hoist to tie the slide section and tension the hoist. Under the stress of the hoist, open all the locking devices of the slide section. After removing the load-bearing shoe, lift the slide section upward along the attachment rail to make the slide section detach from the attachment rail. Remove the fixing bolts of the last attachment rail and lift the last attachment rail to the ground.

[0016] The beneficial effects of the slipform construction method for storage tanks provided by the present invention are as follows: Compared with the prior art, the present invention solves the rigid constraint problem of internal and external linkage and synchronous lifting in the traditional slipform system by setting the inner mold frame unit and the outer mold frame unit to perform lifting actions independently.

[0017] Based on this structural improvement, once the tank wall has been raised to the design elevation, the inner and outer formwork units can be adjusted to different elevations according to the needs of the process, without having to completely dismantle or extensively modify the entire formwork system. That is, after the tank wall construction is completed, the formwork can be moved away from the concrete surface, and the entire formwork system can be lowered and locked at the bottom elevation of the ring beam. The inner formwork unit can then be used directly as a support platform for constructing the tank top ring beam structure. The operating space required for ring beam construction can be obtained through the raising and lowering of the formwork itself, without the need to rebuild the support system. After the ring beam construction is completed, the outer formwork unit can be independently lowered along the track, serving as an operating platform for prestressing tensioning and secondary structure construction, continuing to support subsequent processes.

[0018] Throughout the construction process, the formwork system remains attached to the tank wall track. By adjusting the formwork in two different directions, the operational requirements for ring beam construction and prestressed construction can be met sequentially. This avoids repeated disassembly and modification of the formwork, eliminating the large amount of manpower, machinery, and time wasted.

[0019] Meanwhile, since the inner and outer formwork are each equipped with independent drive and control systems, they can be raised and lowered at optimal speeds without interfering with each other, further improving the smoothness of process transitions. The construction rhythm is no longer interrupted by the disassembly and assembly of the formwork, and various trades can carry out continuous construction on the stable working platform provided by the formwork. This shortens the transition time between tank wall construction, ring beam construction, and prestressing construction while ensuring construction safety and quality, thereby improving the overall construction efficiency of the storage tank project. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 A flowchart of a slipform construction method for a storage tank provided in an embodiment of the present invention. Detailed Implementation

[0022] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0023] Unless otherwise explicitly specified, the use of terms such as "first," "second," or "third" is intended to distinguish different objects, not to describe a specific order.

[0024] Unless otherwise expressly defined, the use of directional terms such as “center,” “lateral,” “longitudinal,” “horizontal,” “vertical,” “top,” “bottom,” “inner,” “outer,” “upper,” “lower,” “front,” “rear,” “left,” “right,” “clockwise,” “counterclockwise,” “high,” and “low” to indicate orientation or positional relationships is based on the orientation and positional relationships shown in the accompanying drawings and is only for the convenience of describing the invention and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the specific scope of protection of the invention.

[0025] This invention addresses the lack of construction organization flexibility caused by the coordinated operation of inner and outer formwork in existing slipform construction techniques for storage tanks. It proposes a slipform construction method for storage tanks based on an attached self-climbing formwork system. The improvement of this formwork system lies in the fact that the inner and outer formwork units are each equipped with independent drive and control systems, allowing them to perform lifting and lowering actions independently without mutual constraint. This decoupled structural design enables the formwork system to adapt to the spatial requirements of each process—the tank wall slipforming stage, the ring beam construction stage, and the prestressing construction stage—using different lifting combinations. Thus, a single assembly can cover the entire construction process of the main tank structure without the need for disassembly or modification.

[0026] Please see Figure 1 In a specific implementation, the technical solution of the present invention unfolds sequentially according to the construction timeline, and sets up five main steps: assembly of the formwork system, initial slip and trial lifting, continuous slip operation, ring beam construction, and prestressed construction.

[0027] Step S1 details the assembly process of the formwork system from scattered components to a complete construction function, including track fixing, power unit installation, operation platform erection and system debugging.

[0028] Step S2 addresses the technical challenges of the slipform construction startup phase, namely, how to safely and smoothly transition the formwork from a static state to a continuous slip-lift state while ensuring that the concrete strength meets the standards. The trial lifting process in this step includes a refined control process such as inspecting all power units one by one, reading levelness data, and switching the load-bearing guidance function.

[0029] Step S3 covers all the work content of the main stage of slipform construction, including track splicing and installation, reinforcement layout, prestressed channel pre-embedding, concrete layered pouring and vibration, and finishing and curing of the demolded concrete. It is the part of the technical solution of this invention with the most concentrated process and the most close cooperation among various trades.

[0030] Step S4 involves the final sliding treatment after the tank wall reaches the design elevation, the retraction of the formwork, and the conversion of the ring beam construction platform.

[0031] Step S5 utilizes the independent lifting function of the outer formwork unit to transform it into a working platform for prestressing tensioning and secondary structure construction.

[0032] Example 1 This embodiment uses a 40,000 m³ full-containment LNG storage tank in an LNG storage facility as an example. The tank adopts a double-wall structure design, with the inner tank storing LNG and the outer tank being a prestressed reinforced concrete structure. The concrete outer tank has an inner diameter of 48 m, a wall thickness of 700 mm, and a height ranging from 2,700 m to 34,400 m. The tank body is made of C50 low-temperature concrete, with ordinary steel reinforcement of HRB400E and low-temperature steel reinforcement of HRB500. The prestressing system adopts the post-tensioning method, with prestressing tendons of standard type 1×7, a diameter of 15.7 mm, and a steel ultimate strength of 1860 N / mm².

[0033] S1: Assembly of the formwork system An attached, self-climbing formwork system is assembled on the top surface of the tank foundation (2.7m above the foundation). The formwork system consists of inner and outer formwork units, each equipped with an independent drive system and control system, enabling independent lifting and lowering operations. The formwork system has four vertical working platforms: from top to bottom, the pre-construction working layer, the core construction layer, the finishing and curing layer, and the painting layer. The formwork of the inner and outer formwork units encloses the tank wall casting chamber.

[0034] The painted layer is located below the repair and maintenance layer. The painted layer is detachably connected to the main frame of the repair and maintenance layer through a telescopic connecting frame. The telescopic connecting frame is composed of multiple H-beams. One end is fixed to the frame of the repair and maintenance layer by high-strength bolts, and the other end is connected to the frame of the painted layer by a pin. It has bidirectional adjustment freedom of vertical extension and horizontal extension.

[0035] The painted layer itself is equipped with an independent lifting and adjusting mechanism, such as a small hydraulic cylinder and guide column, as well as a horizontal telescopic mechanism, such as a two-way spiral screw and guide rail.

[0036] The formwork system is equipped with attached rails, which are non-embedded supports made of 200×100×5mm rectangular tubing. An 8# channel steel is welded to each side to form a protruding structure. A 5mm thick steel plate is welded to the side of the rectangular tubing closest to the concrete to create rounded corners. The steel plate contacts the concrete during construction. One side of the rail is attached to the concrete wall, bearing the load and providing climbing guidance for the formwork system. The rails are available in 4.5m, 3m, and 1.5m lengths, and are secured end-to-end with M30×150 hex bolts. The rail material is Q355B, with a straightness deviation ≤2mm / m and a height difference at the joint ≤1mm.

[0037] The mold frame's power unit comprises 24 sets, 12 on the outer side and 12 on the inner side. Each set includes a slide section, a main hydraulic cylinder, a load-bearing shoe, and a locking hydraulic cylinder. The main hydraulic cylinder has a thrust of 470kN and a stroke of 1010mm. The slide section is welded from steel plates and features internal roller rows to reduce sliding resistance. It also incorporates a displacement sensor and hydraulic circuit control device. The control system uses two host computers to independently control the inner and outer mold frames, with a built-in PLC enabling the mold frame to be lifted slowly and continuously at a uniform speed.

[0038] The specific steps for assembling the mold frame include: (1) Base surface treatment: roughen the tank wall area, use an electric hammer to drill holes with a diameter of 25mm and a depth of not less than 150mm at the corresponding position of the track base, insert 4 M20 chemical anchors, and clean the base surface.

[0039] (2) Install the track fixing embedded panel: Install the 4 nuts under the panel at the elevation of 2.73m on the track base panel and adjust them to be at the same level. After installing the embedded panel, install the 4 nuts on the panel and tighten them.

[0040] (3) Install power unit: Install a set of power units simultaneously inside and outside, hoist the inner and outer rails into the slide section, lift them to the installation position and weld them to the embedded panel, and install the bottom set of anchors.

[0041] (4) Install the main operating platform: install the truss sections and slide sections of the pre-assembled template section by section, install the pins and insert the B-type pins to prevent them from falling off, and install the operating platform extension parts and railings section by section.

[0042] (5) Two-way installation of main platform and auxiliary operation platform: Equipped with forklifts and tower cranes to extend to both sides, install main platform and auxiliary platform accessories, including guardrails, stair passages, power supply, host computer, etc.

[0043] (6) Equipment debugging: Add hydraulic oil to the hydraulic pump station in each slide section and debug it. Drive the main hydraulic cylinder one by one to make it make firm contact with the pad placed on the foundation surface. Start each one to level it with the highest set of slide sections as the standard, and seal the gaps between the template and the foundation and between the templates.

[0044] S2: Initial Sliding and Trial Lifting The initial concrete section is poured in layers within the casting chamber of the tank wall. The first layer of concrete is poured in layers, each 30cm high. The pouring speed, simulating the normal slip-lift stage, is controlled at 2.5 hours per layer to avoid unstable speed after the lifting begins due to excessively high pouring layers or excessively fast pouring speed. The concrete vibration depth is controlled at the height of the poured layer plus 5cm, and excessive insertion is strictly prohibited.

[0045] After the bottom layer of concrete reaches its initial setting strength, the formwork system will be raised for trial operation, which includes the following steps: S21: After the first layer of concrete is poured, the setting state of the bottom layer of concrete is checked. Once the bottom layer of concrete reaches the demolding strength (not less than 0.2MPa), the formwork system is started, and the formwork system is raised slightly by one stroke height (about 25cm). After the slight rise is completed, the formwork system is stopped, and the operating conditions of all 24 power units are inspected one by one to check the sealing status of the hydraulic cylinders, the position of the locking device, and the uniformity of the separation between the formwork and the concrete wall.

[0046] S22: After the inspection is completed, the control system continuously climbs to the set test height at a set speed (approximately 10cm / h). During the continuous climbing process, the upper computer control system reads the displacement data of each power unit displacement sensor in real time, reads and records the level deviation data of the inner and outer mold frame units. Levelness correction is performed every 25cm. If the height difference exceeds the set limit of 20mm, the lifting operation is automatically terminated and an electric bell is activated as a reminder.

[0047] S23: After the formwork system is raised to the set test height, measure and record the penetration resistance value of the concrete in the formwork, check the appearance quality of the concrete in the formwork and record the flow, collapse and cracking.

[0048] S24: After measurement and inspection, continue lifting the mold frame system until the locking device inside the slide section aligns with the set hole (0.75m height hole) on the attachment rail. Stop lifting and lock the slide section to the attachment rail, then retract the main hydraulic cylinder. After the main hydraulic cylinder retracts, install the load-bearing shoe and lock it to the 0.25m height hole on the attachment rail. Release the locking relationship between the slide section and the attachment rail, transferring the load-bearing and guiding functions of the mold frame system to the load-bearing shoe. After the locking relationship is released, proceed with continuous slipforming operations.

[0049] S3: Continuous slipway operation The formwork system maintains a constant speed and continuous climbing. During the slipforming process, the steel reinforcement layout, installation of embedded parts and prestressed channels, concrete pouring and vibration, and concrete finishing and curing operations are completed simultaneously on the four working platforms.

[0050] (a) Track installation The track is installed using a segmented splicing method. Before installation, the inner and outer attached tracks, positioning cones, anchor bars, and joint connecting plates are pre-assembled on the ground according to the tank wall thickness (700mm). After assembly, a special track hoisting tool is used to hoist the entire attached track to the installation position. During track installation, construction workers stand on the pre-work layer to connect and fix the attached tracks.

[0051] The track height is designed as follows: top elevation of the foundation 2.7m, top elevation of the tank wall 34.4m, bottom elevation of the ring beam 32.4m, height from the foundation to the bottom of the ring beam 29.7m, and track height 0.18m above the ground. Both the inner and outer sides use a 4.5m×5+3m×3 configuration, i.e., five 4.5m long tracks plus three 3m long tracks, for a total length of 31.5m, extending 1.8m above the bottom of the ring beam for empty slip demolding.

[0052] (ii) Reinforcement Layout The reinforcement bar placement work is completed collaboratively between the pre-construction work layer and the core construction layer: On the pre-work layer, the vertical reinforcement bars are spliced ​​after the spacing and protective layer are controlled by the reinforcement positioning sleeves. The vertical reinforcement bars are configured according to the design requirements, with a 1 / 4 staggered splice, a fixed length of 6000mm, and the lap length is as required by the design. The joint positions are staggered, and the cross-sectional area of ​​the reinforcement bars at any horizontal section is ≤50%. Reinforcement positioning sleeves are installed on the auxiliary platform slab, and the vertical reinforcement bars are fitted into the positioning sleeves to ensure the spacing and protective layer of the vertical reinforcement bars.

[0053] On the core construction layer, use chalk to draw the spacing lines for the circumferential horizontal reinforcement on the vertical reinforcement, and tie the circumferential horizontal reinforcement according to the spacing lines. The circumferential horizontal reinforcement is 12000mm in length, with lap lengths as required by the design. The joint positions are staggered, and the horizontal lap length of the joint is not less than one lap length and not less than 1000mm. Within the same vertical section, one lap joint is allowed every three reinforcements. The inner and outer horizontal reinforcements are evenly staggered. Leave a gap of about 2m between the top of the formwork and the auxiliary platform to facilitate the threading of the circumferential reinforcement, ensuring that at least two tied horizontal reinforcements are visible on the concrete surface.

[0054] Tie hooks are installed between the inner and outer layers of reinforcing bars. The joints of the vertical reinforcing bars are staggered, and the joints of the circumferential horizontal reinforcing bars are also staggered.

[0055] (III) Installation of prestressed channel The installation of prestressed channels and the laying of reinforcing bars are carried out simultaneously and in parallel, following the principles of "positioning first, then construction; priority given to embedded parts and matching of reinforcing bars; simultaneous fixing and mutual security; and acceptance of each section".

[0056] (1) Installation and calibration of positioning template: Install the positioning template on the template system. Select two 50×2 square tubes for custom processing. According to the positioning parameters of the prestressed accessories, accurately reserve the fixing holes for anchor plates, trumpet tubes, and corrugated tubes. The hole position deviation is controlled within 3mm. Hoist the template to the slipform operation platform, align it with the positioning reference line on the template and place it against the side template of the buttress column. Use spot welding or special buckles to firmly fix the template to the slipform template. Calibrate the verticality, horizontality and hole position elevation of the template.

[0057] (2) Anchor plate installation: Seal the front hole of the anchor plate tightly with a custom-made steel plate and reinforce it with sealing tape. Align the sealed anchor plate with the reserved fixing hole of the template frame and place it against the inner wall of the side formwork of the buttress column, ensuring that the center line of the anchor plate is completely coincident with the center line of the prestressed duct. Securely connect the anchor plate to the positioning template frame and the surrounding steel reinforcement cage with bolts or welding. Single-point fixing is strictly prohibited.

[0058] (3) Installation of spiral reinforcement: After the anchor plate is installed and calibrated, the spiral reinforcement is placed on the prestressed duct at the rear end of the anchor plate, closely attached to the surface of the anchor plate, ensuring that the center of the spiral reinforcement coincides with the center of the anchor plate. The spiral reinforcement is tied or spot-welded to the surrounding structural reinforcement and vertical reinforcement, with the fixing points evenly distributed, and the number of turns and spacing strictly conforming to the design requirements.

[0059] (4) Installation of the trumpet tube: Align the large end of the trumpet tube with the hole at the rear end of the anchor plate, and connect the small end to the corrugated pipe. Ensure that the pipe axis is straight without bends or misalignment throughout the process. Use sealing tape to tightly wrap the joint between the trumpet tube and the anchor plate and the corrugated pipe to prevent grout leakage. At the same time, tie the trumpet tube to the positioning template and the steel reinforcement cage to enhance the overall stability.

[0060] (5) Corrugated pipe installation: Cut the material according to the height and circumferential length of the slipform section. The length of each section should be adapted to the slipform working space. Use a pipe bender for cold bending. The bending radius should meet the specifications and be strictly prohibited from flattening or cracking. One end of the corrugated pipe should be precisely connected to the small end of the trumpet pipe using a special sleeve. The joint should be sealed with sealing tape. Lay the corrugated pipe along the circumferential direction to the corresponding anchor end. It should be fixed by positioning steel bars throughout the entire process. The spacing of the positioning steel bars should be ≤1m, and the spacing should be ≤0.6m for curved sections. Securely tie the corrugated pipe to the positioning steel bars and the surrounding steel bars. After installation, use a tester to ensure that the pipeline is unobstructed. Before lifting the slipform, reserve sufficient overlap length for the upper corrugated pipe. Wrap the reserved end with a sealing cap to prevent debris from entering.

[0061] (iv) Concrete pouring Concrete pouring adopts a layered symmetrical pouring method. The pouring height of each layer is controlled at 30cm, and the pouring direction of each layer of concrete is opposite to that of the previous layer (the concrete is poured into the formwork and vibrated simultaneously in both directions) to avoid cold joints at the end of unidirectional construction. The top surface of the concrete should be 5cm lower than the opening of the formwork.

[0062] Concrete is pumped into the formwork by a truck pump located in the center of the storage tank, and is supplied by four 8m³ concrete mixer trucks. The concrete supply capacity is controlled at 16 cubic meters per hour.

[0063] After the concrete is poured into the formwork, it is vibrated using an immersion vibrator (ZN50 type), following the "quick insertion, slow withdrawal" and "vibrator-to-vibration" method, using parallel vibration. Each point should be vibrated for 20-30 seconds. Vibration should be stopped when the concrete surface no longer shows significant settling, no air bubbles appear, and a layer of cement paste forms on the surface. When vibrating the upper layer of concrete, the vibrator should not penetrate more than 5cm into the lower layer to eliminate the joint between the two layers. Under-vibration and over-vibration are strictly prohibited. The initial setting time of the concrete should be controlled at 8-10 hours, and the slump should be controlled at 180-210mm.

[0064] (v) Concrete finishing and curing after demolding The finishing and curing work of the demolded concrete is carried out on the finishing and curing layer. As the formwork system is raised, the original slurry is rubbed out on the surface of the demolded concrete using a plastic scrubbing board and then smoothed with an iron plate.

[0065] On the side of the curing layer closest to the tank wall, a plastic pipe is laid in a ring along the inner wall of the tank, connecting the spray pipes to form a closed-loop spray circuit. Holes are drilled evenly every 20cm along the laid plastic pipes, with a diameter controlled at 1.5mm. Water is sprayed onto the concrete surface of the tank wall through these holes for curing. Spray curing is carried out continuously during the day, and spraying is suspended and the water supply valve is closed at night.

[0066] Curing time control: The C50 concrete in this project is a high-strength concrete, and it contains admixtures such as fly ash. The curing time shall not be less than 28 days. The concrete strength must reach more than 85% of the design strength, and the curing spraying facilities can only be removed after on-site testing and technical verification.

[0067] (vi) Simultaneous decoration work on the painted layer During the continuous slipforming process, the painted layer, located below the finishing and curing layer, rises synchronously with the entire formwork system and undergoes decorative operations. Given that the surface of the concrete after the finishing and curing layer has been smoothed and polished, although it has initially set, it still possesses a certain degree of plastic adhesion. Therefore, the painted layer is installed approximately 1.2m to 1.5m below the finishing and curing layer. Within this height range, the concrete surface has sufficient strength to withstand the painting operation without causing dents or damage. Simultaneously, its internal capillaries are not completely sealed, which facilitates the micro-penetration and bonding of the colored paint, improving color adhesion.

[0068] The horizontal telescopic mechanism of the painted layer drives the painted template frame to extend or retract radially along the tank wall according to the width of the design pattern, allowing the painted template to fit snugly or very close to the tank wall surface. Simultaneously, an independent lifting adjustment mechanism fine-tunes the vertical height of the painted template to precisely match the vertical positioning of the pattern on the tank wall. The surface of the painted template is engraved with raised textures or hollow patterns according to design requirements and has a built-in colored paint supply system. As the painted layer rises uniformly with the template frame at a set speed, the painted template adheres closely to the initially set concrete surface of the tank wall. Through extrusion, roller coating, or spraying, continuous colored decorative stripes, elevation marking lines, company logos, or functional warning stripes are simultaneously formed on the concrete surface, achieving integrated construction of slipforming and painting.

[0069] The horizontal extension and retraction of the painted layer, as well as its lifting and fine-tuning movements, are linked to the main control system of the mold frame via a field-programmable logic controller (FPGA). When the mold frame is in a uniform sliding motion (e.g., 10 cm / h), the control system automatically calculates the intermittent movement cycle of the painted layer based on the preset longitudinal spacing of the pattern, achieving a step-by-step painted operation of rising, positioning, and rolling. After the painted operation is completed, as the mold frame continues to rise, a flexible scraper and hot air device located behind the painted layer instantly dry and cure the painted surface, preventing scratches or contamination during subsequent lifting processes.

[0070] S4: Ring Beam Construction After the tank wall is raised to the design elevation, the final sliding construction begins. When there is about 1 meter remaining from the top elevation of the tank wall, the levelness of the formwork is checked to ensure that the formwork is raised at the same height and construction is synchronized. The concrete adhering to the formwork surface is cleaned to make the surface smooth as close as possible to the initial sliding state. The final layer of concrete is poured and measured simultaneously, with the pouring height being the tank wall height plus 2 cm, to ensure that the concrete surface is of uniform height and flat.

[0071] After the concrete pouring is completed, the formwork is lifted at a speed of approximately 30 cm / h until the concrete surface is in a relatively flat area on the formwork surface. The lifting speed is then slowed down to near normal construction speed, and the formwork is lifted again for re-vibration to smooth the concrete surface. The concrete surface is inspected as the formwork is lifted; any uneven areas are promptly vibrated to smooth them and repaired simultaneously, until the outer formwork is completely detached from the concrete. The lifting speed and height of the inner formwork are determined based on the possible lifting distance, ensuring demolding is completed before reaching the top of the F-frame, which serves as a limiting support at the top of the formwork.

[0072] After the final sliding is completed, the formwork is moved backward to detach from the concrete surface. The specific operation includes: removing the connecting bolts at the round holes between the formwork and the curvature control plate, keeping the connecting bolts at the elongated holes between the formwork and the curvature control plate, and moving the formwork together with the curvature control plate backward along the guide direction of the elongated holes to detach the formwork from the concrete surface.

[0073] After the formwork is detached from the concrete surface, the formwork system is lowered and locked at the working elevation. Lowering the formwork makes the elevation of the upper surface of the core construction layer lower than the elevation of the bottom of the ring beam (32.4m). This ensures that the locking device pin in the slide section is concentric with the bushing hole on the attached track. The locking device pin is then inserted into the track to lock, ensuring that all four locking pins of each unit are in the locked state.

[0074] Remove the inner ring paving (which conflicts with the ring beam) and the extended section of the skeleton from the pre-work layer of the outer formwork unit, and retain the outer ring paving as the ring beam construction platform. Erect the bottom formwork of the ring beam on the core construction layer, and construct the tank top ring beam structure using the inner formwork unit as support.

[0075] S5: Prestressed construction and secondary structure After the construction of the tank top ring beam structure is completed, the outer formwork unit is lowered along the track, serving as an operating platform for prestressing tensioning and secondary structure construction. Specifically, this includes: After the ring beam construction is completed, the ring beam formwork and formwork supports are removed and the area is cleaned to the ground. The appearance of the ring beam concrete surface is repaired. According to the needs of prestressed construction, the formwork is used as a lifting and lowering platform to facilitate prestressed construction. When constructing the prestressed sealing concrete, a formwork with a height of 3.475m is installed, with its bottom flush with the bottom of the core construction layer and its top flush with the slab of the preceding working layer. A slipform process is used for concrete construction.

[0076] After the prestressing tensioning is completed, the secondary structural concrete construction is carried out using the outer formwork unit. After all the work is completed, the formwork system is lowered to the foundation surface and dismantled.

[0077] dismantling of formwork system The dismantling of the formwork system includes the following steps: S101: Clear the remaining construction materials and tools from the four-layer work platform to the ground, temporarily fix the movable paving board, and before removing the painted layer, disconnect its independent hydraulic pipeline and paint supply pipeline, and clean the residual paint in the painted template; then release the pin connection of the telescopic connecting frame, and use the lifting device of the template itself or the auxiliary tower crane to lift the painted layer to the ground as a whole, and then remove the repair and maintenance layer in the original order.

[0078] S102: Lower the inner and outer formwork units simultaneously. During the descent, remove the fixing bolts of the attachment rails and positioning cones that have detached from the concrete wall above the core construction layer one by one, and hoist the attachment rails to the ground in sections. Remove the rails section by section after the rail joints are higher than the core construction layer, until only the bottommost attachment rail remains.

[0079] S103: Lower the formwork system to the bottom of the finishing and curing layer, close to the foundation surface. Remove the finishing and curing layer in the following order: first remove the guardrails, then the paving boards, and finally the L-shaped frame. Hoist the removed components to the ground.

[0080] S104: Continue lowering the formwork system. Dismantle the front working layer in the following order: first remove the guardrails, then the decking, and finally the L-shaped frame. Simultaneously remove the corresponding operating platform extensions and railings of the front working layer.

[0081] S105: Starting from the power unit at the location of the control system, dismantle the core construction layer truss section by section in the order of removing the template, curvature control panel, guardrail, railing, operating platform extension, and truss. After dismantling to the slide section position, disconnect the power unit's power cord and communication cable, open all locking devices of the power unit, and disassemble the power unit in the order of removing the attached rail, load-bearing shoe, slide section template, and auxiliary components. Hoist the slide section to the ground.

[0082] S106: When dismantling the last power unit, use a lifting hoist to secure the slide section and tension the hoist. Under load, open all locking devices of the slide section, remove the load-bearing shoe, and lift the slide section upwards along the attachment rail to disengage it from the attachment rail. Remove the fixing bolts of the last attachment rail and lift the last attachment rail to the ground.

[0083] Example 2 The difference between this embodiment and Embodiment 1 lies in the following features of active pre-biasing and correction operation for verticality.

[0084] During the slipform construction process, in addition to relying on the formwork control system to ensure the overall levelness of the formwork, this embodiment adopts an active pre-deviation correction method to precisely control the verticality of the tank wall.

[0085] Specifically, based on daily verticality measurement records (12 monitoring points evenly distributed around the tank circumference, measured using a 10kg plumb bob), adjustments were made to locations with verticality deviations exceeding 15mm. The adjustment method is as follows: (1) Adjustment is made by manually tilting the track in the correct direction. When the measurement shows that a certain point is offset by 16mm towards the inside of the tank, it is planned to continue sliding for another 5m to restore the verticality to within 5mm. The track is tensioned outwards using a tensioning device to tilt it. The track is measured at a point 5m above the upper surface of the template. The tensioning causes the track to offset outwards from the tank wall by 10mm from the upper surface of the template. The track is then returned to its original position after a 5m height.

[0086] (2) The track is fixed by welding the anchor bars with steel bars for positioning.

[0087] (3) Remove the tensioning device.

[0088] In addition, for slight deviations, such as 8mm, adjustments are made by stacking construction materials. Reinforcing bars are hoisted and stacked to the outer core construction layer of the deviation point, so that the load on the outer formwork is greater than the load on the inner formwork.

[0089] In terms of verticality prevention, diagonal bracing is added between the anchor bars of the pre-assembled track for reinforcement, which effectively reduces structural displacement during construction.

[0090] Example 3 The difference between this embodiment and Embodiment 1 and Embodiment 2 lies in the following differentiated slip speed control operation characteristics under high temperature conditions.

[0091] When the ambient temperature during construction exceeds 35°C, this embodiment adopts a differentiated slip-lift speed control strategy.

[0092] Specifically, in high-temperature environments, retarders are added to concrete to extend the initial setting time. Based on real-time temperature monitoring data, the normal slipform speed (10 cm / h) is increased by 20% to 12 cm / h to shorten the residence time of concrete in the formwork and prevent premature setting and adhesion to the formwork due to high temperatures.

[0093] Meanwhile, the raw materials for concrete are cooled: sand and gravel are shaded and cooled, and ice is added to the sand and gravel if necessary; cement is transported to the warehouse to cool before use; and low-temperature water is used to mix the concrete, with the water temperature not exceeding 20℃.

[0094] Regarding the organization of the pouring operation, the pouring time was adjusted to avoid the midday high-temperature period (11:00-15:00), and the main pouring operations were scheduled for the early morning and evening. The adhesion of the formwork was checked every 30 minutes, and the frequency of applying the release agent was increased if necessary.

[0095] After the concrete is demolded, curing should be strengthened. Based on the existing spraying system of the curing layer, an auxiliary spraying device should be added to ensure that the concrete surface remains continuously moist.

[0096] Example 4 The difference between this embodiment and embodiments one through three lies in the following characteristics of the formwork wind-resistant reinforcement operation under strong wind conditions.

[0097] When the wind speed reaches level 6, this embodiment adopts wind-resistant reinforcement measures by adding inclined cables.

[0098] Specifically, Φ22 stay cables are added to the outside of the formwork system, with a spacing of ≤6m. One end of the stay cable is connected to the core construction layer skeleton of the formwork, and the other end is anchored to the pre-embedded anchor points on the completed tank wall. The tension of the stay cables is adjusted using turnbuckles to ensure that each stay cable is subjected to uniform force.

[0099] The live load on the operating platform is limited to 1.5 kN / m² (normal operating condition is 3 kN / m²) to reduce platform sway under wind load. Anemometers monitor in real time, and the frequency of verticality checks is increased to once every 15 minutes.

[0100] Construction must cease when winds reach force 8. Before halting construction, secure all movable equipment and materials on the operating platform, and inspect and reinforce safety measures. Prepare sufficient guy ropes and anchoring devices, and temporarily anchor the platform if necessary.

[0101] Before resuming construction, a comprehensive inspection of the cable anchor points and formwork nodes must be conducted to ensure that there is no loosening or deformation before work can resume.

[0102] Example 5 The difference between this embodiment and embodiments one through four lies in the following operational features for determining the stoppage of sliding formwork during continuous construction in rainy weather.

[0103] This embodiment establishes a graded method for determining when to stop sliding during construction in rainy weather.

[0104] Specifically, when rainfall is light and the expected duration of rain is short, slipform construction can continue. In this case, the vibrator operator should stand on the inside so that the concrete pouring surface is higher on the outside and lower on the inside, avoiding grout buildup on the outer surface.

[0105] When the rainfall is heavy but the expected duration is short, concrete pouring can be stopped and the formwork can continue to slide and lift. When the rain stops, the concrete mix ratio should be adjusted in time (aggregate reduced by half) and the concrete vibration at the bonding surface should be strengthened.

[0106] If none of the above conditions are met (such as continuous heavy rain or torrential rain), take immediate measures to stop the sliding process. The stopping procedure includes: raising the formwork to the designated stopping position, cleaning the formwork surface, and covering and protecting the poured concrete surface. After the rain stops, treat the joint surface according to the horizontal construction joint procedure, and prohibit continuous work during rainy weather.

[0107] Before resuming work after the rain, a comprehensive inspection of the formwork system should be carried out, with a focus on checking the sealing of the hydraulic system, the insulation performance of electrical equipment, and the anti-slip measures of the operating platform. Work can only resume after safety is confirmed.

[0108] VI. Industrial Applicability The slipform construction method for storage tanks provided by this invention utilizes a technical solution of independent lifting and lowering of the inner and outer formwork units. This allows the entire process of tank wall slipforming, ring beam construction, and prestressing construction to be completed sequentially after a single assembly of the formwork system. This avoids the drawbacks of repeated disassembly and modification of the formwork in traditional construction, significantly improving construction efficiency and safety. This method is particularly suitable for tank wall construction in large storage tank projects such as LNG full-containment tanks and has broad prospects for widespread application.

[0109] 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, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A slipform construction method for storage tanks, characterized in that, Includes the following steps: S1: Assemble an attached self-climbing formwork system on the top surface of the storage tank foundation. The formwork system is divided into an inner formwork unit and an outer formwork unit that can independently perform lifting and lowering actions. The formwork system is equipped with multiple working platforms along the vertical direction. The templates of the inner formwork and the templates of the outer formwork enclose each other to form a tank wall casting chamber. S2: The initial section of concrete is poured in layers in the casting chamber of the tank wall. After the bottom layer of concrete reaches the initial setting state, the formwork system is started for trial lifting. After the debugging and operation are normal, the continuous slip-lift operation is started. S3: The formwork system maintains a uniform and continuous climbing speed. During the slip-lifting process, the steel reinforcement layout, installation of embedded parts and prestressed channels, concrete pouring and vibration, and concrete finishing and curing operations are completed synchronously on the multi-layer working platform. S4: After the tank wall is raised to the design elevation, the template is moved backward to detach from the concrete surface, the formwork system is lowered and locked at the working elevation, and the tank top ring beam structure is constructed with the inner formwork unit as support. S5: After the construction of the tank top ring beam structure is completed, the outer formwork unit is lowered along the track, so that the outer formwork unit serves as an operating platform for prestressing tensioning and secondary structure construction.

2. The slipform construction method for a storage tank as described in claim 1, characterized in that, In S1, the multi-layer work platform consists of, from top to bottom, a pre-work layer, a core construction layer, a repair and maintenance layer, and a painting layer. The inner mold frame unit and the outer mold frame unit are respectively equipped with independent drive systems and independent control systems, and the inner mold frame unit and the outer mold frame unit independently perform lifting and lowering actions; The formwork system is equipped with an attachment rail, which is a non-embedded structure. The attachment rail is attached to the concrete wall on one side and bears the load-bearing function and climbing guidance function of the formwork system. The painted layer is located below the repair and maintenance layer. The painted layer is detachably connected to the skeleton of the repair and maintenance layer through a telescopic connecting frame. The painted layer has an independent lifting adjustment mechanism and a horizontal telescopic mechanism. The painted layer is used to climb synchronously with the mold frame system and form decorative patterns or marking stripes on the surface of the demolded concrete.

3. The slipform construction method for a storage tank as described in claim 2, characterized in that, In S2, the trial lifting operation includes the following steps: S21: After the first layer of concrete is poured, the setting state of the bottom layer of concrete is checked. After the bottom layer of concrete reaches the demolding strength, the formwork system is started and the formwork system is controlled to rise slightly by one stroke height. After the slight rise is completed, the formwork system is stopped. The operating conditions of all power units are inspected one by one to check the sealing status of the hydraulic cylinder, the position of the locking device, and the uniformity of the separation between the formwork and the concrete wall. S22: After the inspection is completed, the mold frame system is controlled to continuously climb to the set test height at a set speed. During the continuous climbing process, the displacement data of each power unit displacement sensor is read in real time through the host computer control system, and the level deviation data of the inner and outer mold frame units is read and recorded. S23: After the formwork system has climbed to the set test height, measure and record the penetration resistance value of the concrete in the formwork, check the appearance quality of the concrete in the formwork and record the flow, collapse and cracking. S24: After measuring the penetration resistance value of the concrete and checking the appearance quality of the concrete, continue to lift the formwork system until the locking device in the slide section is aligned with the set hole on the attachment rail. Stop lifting and lock the slide section to the attachment rail. Retract the main hydraulic cylinder. After the main hydraulic cylinder is retracted, install the load-bearing shoe and lock the load-bearing shoe to the set hole on the attachment rail. Release the locking relationship between the slide section and the attachment rail. Transfer the load-bearing and guiding functions of the formwork system to the load-bearing shoe. After the locking relationship is released, continue the continuous sliding operation.

4. The slipform construction method for a storage tank as described in claim 2, characterized in that, In S3, the attachment rail is installed in a segmented manner. Before the rail is installed, the inner and outer attachment rails, positioning cones, anchor bars and joint connecting plates are assembled into a whole on the ground according to the tank wall thickness. After the assembly is completed, a special lifting tool is used to lift the attachment rail as a whole to the installation position. After the attachment rail is lifted to the installation position, the construction personnel stand on the pre-work layer to carry out the joint fixing of the attachment rail.

5. The slipform construction method for a storage tank as described in claim 2, characterized in that, In S3, the rebar placement operation is completed collaboratively between the preceding work layer and the core construction layer, including: After controlling the spacing and protective layer of the vertical reinforcing bars through the reinforcing bar positioning sleeve on the pre-work layer, the vertical reinforcing bars are extended; on the core construction layer, the spacing lines of the circumferential horizontal reinforcing bars are marked on the vertical reinforcing bars and the circumferential horizontal reinforcing bars are tied according to the spacing lines; hooks are set between the double-layer reinforcing bars on the inner and outer walls; the joints of the vertical reinforcing bars are staggered and the joints of the circumferential horizontal reinforcing bars are staggered.

6. The slipform construction method for a storage tank as described in claim 1, characterized in that, In S3, the installation of prestressed channel and the laying of reinforcing bars are carried out simultaneously and concurrently, including: Install a positioning template on the formwork system and calibrate its verticality and horizontality; after sealing the front hole of the anchor plate, align the anchor plate with the fixing hole of the positioning template and install it, then fix the anchor plate to the positioning template and the surrounding steel reinforcement skeleton; sleeve a spiral reinforcement on the rear end of the anchor plate and fix the spiral reinforcement to the structural steel reinforcement; connect one end of the flared tube to the anchor plate and the other end of the flared tube to the corrugated pipe, and wrap sealing tape around the joint between the flared tube, the anchor plate, and the corrugated pipe; arrange the corrugated pipe circumferentially and tie it to the positioning reinforcement, leaving an overlap length at the end of the segmented corrugated pipe, and install a sealing cap at the end of the reserved overlap length.

7. The slipform construction method for a storage tank as described in claim 1, characterized in that, In S3, concrete pouring adopts a layered symmetrical pouring method. The pouring height of each layer is controlled within a set range. The pouring direction of each layer of concrete is opposite to that of the previous layer. The concrete is pumped into the formwork by a truck pump located in the center of the storage tank. After the concrete is poured into the formwork, it is vibrated with a vibrator. The vibrator is operated in a quick insertion and slow withdrawal manner. When vibrating the upper layer of concrete, the vibrator is inserted into the lower layer of concrete, and the insertion depth is controlled within the set value.

8. The slipform construction method for a storage tank as described in claim 2, characterized in that, In S3, the finishing and curing work of the demolded concrete is carried out on the finishing and curing layer. As the mold frame system is lifted, the original slurry is rubbed out on the surface of the demolded concrete in sequence using a rubbing board and then smoothed with an iron plate. On the side of the finishing and curing layer near the tank wall, a spray pipe is arranged in a ring along the inner wall of the storage tank. The spray pipe is connected into a closed-loop spray circuit. Spray holes are opened on the spray circuit, and water is sprayed onto the surface of the tank wall concrete through the spray holes for curing.

9. A slipform construction method for a storage tank as described in claim 2, characterized in that, In S4, the operation of retracting the template away from the concrete surface includes: Remove the connecting bolts at the round holes between the template and the curvature control plate, leaving the connecting bolts at the elongated holes. Move the template and the curvature control plate backward along the guide direction of the elongated holes, causing the template to detach from the concrete surface. After the template detaches from the concrete surface, lower the formwork system until the elevation of the upper surface of the core construction layer is lower than the bottom elevation of the ring beam. Align the locking device pin in the slide section with the bushing hole on the attached track. After the locking device pin is aligned with the bushing hole, insert the locking device pin into the bushing hole to lock it. Remove the inner ring paving plate and the extended section of the skeleton of the outer formwork unit's pre-work layer, leaving the outer ring paving plate. Use the outer ring paving plate as the ring beam construction operation platform and support the bottom formwork of the ring beam on the core construction layer.

10. A slipform construction method for a storage tank as described in claim 4, characterized in that, Following S5 is a mold frame system dismantling step, which includes: S101: Remove the construction waste and tools from the four-layer work platform to the ground. The four-layer work platform consists of the pre-work layer, the core construction layer, the repair and maintenance layer, and the painting layer. Temporarily fix the movable paving board. S102: The inner formwork unit and the outer formwork unit are lowered synchronously. During the descent, the fixing bolts of the attachment rails above the core construction layer that have detached from the concrete wall and the positioning cone are removed one by one. The attachment rails are hoisted to the ground in sections and the attachment rails are removed section by section until only the bottom attachment rail remains. S103: Lower the formwork system to the bottom of the repair and maintenance layer, close to the foundation surface, and dismantle the repair and maintenance layer in the order of first removing the guardrail, then removing the paving boards, and finally removing the L-shaped frame. Hoist the dismantled components to the ground. S104: Continue to lower the formwork system, and dismantle the front working layer in the order of first removing the guardrails, then removing the decking, and finally removing the L-shaped frame. Simultaneously remove the operating platform extension and railings corresponding to the front working layer. S105: Starting from the power unit at the control system location, dismantle the core construction layer truss section by section in the order of removing the template, arc control plate, guardrail, railing, operating platform extension, and truss. After dismantling to the slide section position, disconnect the power unit's power line and communication cable, open all locking devices of the power unit, disassemble the power unit in the order of removing the attached track, load-bearing shoe, slide section template, and auxiliary components, and hoist the slide section to the ground. S106: When dismantling the last power unit, use a lifting hoist to tie the slide section and tension the hoist. Under the stress of the hoist, open all the locking devices of the slide section. After removing the load-bearing shoe, lift the slide section upward along the attachment rail to make the slide section detach from the attachment rail. Remove the fixing bolts of the last attachment rail and lift the last attachment rail to the ground.

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