Construction method for lifting high-grade concrete sliding frame fixed mold
Through the slide fixed form lifting process and retarder treatment, the problem of high-grade concrete sticking to the formwork during slipform construction was solved, efficient and low-cost concrete forming was achieved, and the scope of application of the slipform process was expanded.
Patent Information
- Application Number
- CN202511077102.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-01
- Publication Date
- 2025-09-26
AI Technical Summary
The traditional slipform process is difficult to adapt to the viscosity of high-grade concrete, which causes the concrete to be stretched and cracked when it leaves the mold, limiting the scope of application of the slipform process.
The slide-fixed formwork lifting process is adopted, combined with the application of release agent on the inner wall of the formwork, spraying retarder on the construction joints, using machine-made sand instead of natural river sand, and treating the construction joints with high-pressure water washing and retarder to ensure the smooth demoulding of the concrete.
It effectively solves the problem of high-grade concrete sticking to the formwork, improves the molding quality, reduces the difficulty and cost of cleaning construction joints, expands the scope of application of the slipform process, and is suitable for concrete structures with strength grades of C40 and above.
Smart Images
Figure CN120701112A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of engineering construction, and more particularly to a construction method for lifting a fixed formwork of a high-grade concrete slide. Background Art
[0002] The reinforced concrete structures of silos and cylinder walls such as grain depots and chimneys are cast by continuous sliding according to the traditional slipform process, which has the characteristics of fast construction speed, good construction quality, less environmental pollution, high construction efficiency and low construction cost. However, as the strength grade of concrete continues to increase, the amount of cement used in the single mix ratio continues to increase, resulting in increased viscosity of concrete. The traditional slipform process has different adaptability to the increased viscosity of concrete. Practice shows that for concrete strength grades of C35 and below and medium-coarse sand (river sand) with a fineness modulus of 3.2 or above, the required process retarding time configuration is required. The concrete is more adaptable to the traditional continuous sliding and continuous pouring slipform process, and its engineering quality has also achieved satisfactory results. However, for concrete strength grade C40 and above, the traditional continuous sliding and continuous pouring slipform process cannot overcome the serious problem of concrete sticking to the mold due to its high viscosity, and this sticking phenomenon cannot be eliminated by adjusting the mix ratio. The concrete out of the mold is commonly damaged and cracked, which seriously restricts the application scope of the slipform process. In view of this, we propose a construction method of high-grade concrete sliding frame fixed mold lifting. Summary of the Invention
[0003] The purpose of the present invention is to provide a construction method for lifting the fixed formwork of a high-grade concrete slide, aiming to solve the problem that the concrete out of the formwork is damaged or cracked due to sticking to the formwork during the slipform construction of high-grade concrete.
[0004] To solve the above technical problems, the present invention provides the following technical solutions: a construction method for lifting a high-grade concrete slide fixed formwork, the method comprising the following steps:
[0005] S1: Construction preparation, carry out the design of the slipform device. According to the plan layout form, cross-sectional dimensions, structural reinforcement, embedded parts design and configuration of the silo and cylinder wall structure, the factors of the structural opening setting and the load design combination method, and in accordance with the specifications and standards, design and review the design scheme of the hydraulic lifting system, formwork system and operating platform of the slipform device, and the lifting frame to form the sliding frame fixed form lifting system. After the design scheme is reviewed and approved, it will be processed and configured according to the design scheme;
[0006] S2: Concrete mix design and trial mixing. The fineness modulus of the concrete sand should be medium-coarse sand above 3.2. During the laboratory trial mixing stage, a 1m×1m×1m steel plate test box is used to simulate the actual mold bin and the layered pouring method to test the setting time of each layer. In addition, the construction plan is compiled and reviewed;
[0007] S3: Acceptance of the installation of the slipform device, setting the reference axis and the inner and outer formwork edges and the gantry control line, checking and accepting the line setting, carrying out the acceptance of the installation of the first plate reinforcement, installing the fixed gantry, installing the formwork ring beam, installing the inner formwork, installing the main and secondary beams of the inner operating platform and the outer triangular platform, installing and debugging the support rods and jack hydraulic system, installing and accepting the vertical reinforcement of the cylinder wall extension, preliminarily installing the inner and outer hanger rods, installing and accepting the outer formwork, and completing the installation of the sliding frame fixed formwork system;
[0008] S4: Normal sliding cycle. After the upper mold is poured, the surface drying retarder is sprayed on the construction joint after the water is absorbed from the pouring surface. The formwork is intermittently slid 900-1200mm with a stroke of 40mm. The speed of installation and acceptance of steel bars and embedded parts is coordinated. The formwork deflection and verticality of the cylinder wall are checked. The construction joint is flushed with high-pressure water and the construction joint and the inner wall of the formwork are evenly coated with release agent. The pouring is completed in 300mm layers for 900-1200mm. The surface of the original concrete slurry is smoothed and repaired, and then the curing liquid is sprayed on it. The cycle is repeated until the top of the cylinder is completed.
[0009] S5: Dismantle the slipform device. After the cylinder top construction is completed, dismantle the slipform device.
[0010] Preferably, in the above step S2, the retarding time of the concrete is designed to ensure that no cold joints are formed at the junction of the upper and lower layers when the concrete is poured in layers, and that the demoulding strength of the first layer of concrete is 0.2MPa-0.4MPa when the formwork is lifted after the layered pouring of the entire slab is completed.
[0011] Preferably, in the above step S3, it also includes reinforcing the tension screws at the bottom of the formwork and sealing with mortar, pouring 900-1200mm in 300mm layers, spraying surface drying retarder on the construction joint after the pouring surface is water-absorbed, removing the tension screws at the bottom of the formwork, and starting to lift the formwork with a stroke of 40mm according to the retarding time determined by the trial mix, observing the state of the concrete removed from the formwork, checking whether each device of the system is normal, intermittently sliding 900-1200mm at the speed of steel bar installation acceptance, checking the deflection and verticality of the formwork, washing the construction joint with high-pressure water and accepting the construction joint and the inner wall of the formwork, installing internal and external hangers, pouring 900-1200mm in 300mm layers, installing internal and external hangers, spraying surface drying retarder on the construction joint after the pouring surface is water-absorbed, and intermittently sliding the formwork 900-1200mm at a stroke of 40mm to cooperate with the speed of steel bar and embedded parts installation acceptance, and completing the installation of internal and external hangers.
[0012] Preferably, the formwork is evenly coated with a release agent before the first full mold pouring, and a surface retarder is sprayed after the pouring is completed and the formwork is cleaned as it is lifted during the intermittent lifting process of small strokes.
[0013] Preferably, in the above step S4, iron sheets with a thickness of 0.1 mm and a width of 300-500 mm are laid at the positive corners of the structure to isolate the sliding formwork and the solidified concrete at the corners from being disturbed and damaged.
[0014] Preferably, in the above step S2, the sand used for concrete is expanded from natural river sand to machine-made sand. When machine-made sand is used, the content of stone powder below 0.15 mm in the screening test should be controlled below 10%.
[0015] Preferably, in the above step S2, after the whole slab is poured in layers, the pouring resistance value of the first layer of concrete when the formwork is lifted is 0.30KN / cm 2 -1.05KN / cm 2 .
[0016] Preferably, the iron sheet is adhered to the formwork using sticky butter, and no release agent is applied to the concrete surface. When the formwork is lifted, the iron sheet adheres to the concrete surface through bonding force with the concrete surface and is removed after the concrete is demoulded.
[0017] Compared with the prior art, the present invention has the following beneficial effects:
[0018] 1. The present invention adopts a slide fixed mold lifting process, combined with measures such as applying a release agent on the inner wall of the template and spraying a retarder on the construction joint, to effectively solve the problem of high-grade concrete sticking to the mold due to its high viscosity, avoid the concrete from being stretched or cracked after being demolded, improve the concrete molding quality, and ensure the appearance and internal quality of the silo and cylinder wall structure.
[0019] 2. The present invention regards construction joint treatment as a necessary process, and adopts the method of spraying concrete surface retarder combined with high-pressure water flushing before pouring, which greatly reduces the difficulty of cleaning construction joints. Compared with the traditional construction joint chiseling cleaning method, it significantly improves the cleaning efficiency and speed, reduces the cleaning labor cost, and at the same time ensures the quality of construction joint cleaning, makes the construction joint more tightly connected, and improves the stability of the overall structure.
[0020] 3. The present invention expands the sand used for concrete in the slipform process from natural river sand to machine-made sand. Under the condition that the stone powder content below 0.15mm in the machine-made sand screening test is controlled below 10%, the construction quality can still be guaranteed, the flexibility of material selection is increased, and it is helpful to cope with the material supply situation in different regions and reduce the material procurement cost.
[0021] 4. This invention addresses the construction challenges of high-grade concrete while maintaining the advantages of traditional slipform technology: fast construction speed, high quality, minimal environmental pollution, high efficiency, and low cost. This eliminates the limitations of the slipform technology to concrete strength grades and makes it applicable to reinforced concrete vertical shear wall structures with a design strength of C40 or higher. This expands the scope of application of the slipform technology and provides a more reliable construction method for related projects. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 Schematic diagram of the method of the present invention. DETAILED DESCRIPTION
[0023] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.
[0024] Example 1
[0025] According to the plan layout, cross-sectional dimensions, structural reinforcement, embedded parts design and configuration of the silo and cylinder wall structure, the structural opening setting factors combined with the load design combination method, and in accordance with the specifications and standards, the design and review of the hydraulic lifting system, formwork system and operating platform of the slipform device, which together with the lifting frame, constitute the sliding frame fixed mold lifting system design plan. After the design plan is reviewed and approved, it will be processed, produced and configured according to the design plan.
[0026] Machine-made sand with a fineness modulus of 3.4 was selected, and the stone powder content below 0.15mm in the screening test was controlled at 8%. During the laboratory trial mixing stage, a 1m×1m×1m steel plate test box was used to simulate the actual mold bin and layered pouring method to test the setting time of each layer. Considering that the joints of the upper and lower layers cannot form construction cold joints during the layered pouring of concrete, and that the demoulding strength of the first layer of concrete is 0.25MPa when the formwork is lifted after the entire slab is poured in 1.0m layers, and the pouring resistance value of the first layer of concrete is 0.5KN / cm 2 After several trial mixes and adjustments, the final mix ratio was determined and the construction plan was completed.
[0027] Lay out the reference axis, inner and outer template edges, and gantry control lines using a high-precision total station. The laying-out error is controlled within ±1mm, and subsequent construction is carried out after inspection and acceptance.
[0028] During the inspection and acceptance of the first slab reinforcement installation, the reinforcement shall be tied strictly in accordance with the design requirements, and the reinforcement spacing error shall be controlled within ±5mm. After passing the inspection and acceptance by the supervisor, the next step shall be carried out.
[0029] Install and fix the mast, and control the verticality error of the mast installation within ±3mm.
[0030] Install the formwork ring beam and ensure that the flatness error of the ring beam is within ±2mm.
[0031] Install the inner formwork, apply the release agent evenly in advance, and control the gap between the inner formwork and the joints to within ±1mm.
[0032] The main and secondary beams of the inner operating platform and the outer triangular platform are installed. The platform is installed firmly, all connection points are welded firmly, and the weld height meets the design requirements.
[0033] Install the support rod and jack hydraulic system and debug it to ensure that the hydraulic system pressure is stable and the error is controlled within ±0.5MPa.
[0034] The vertical reinforcement of the cylinder wall is installed and inspected, and the internal and external hanger rods are preliminarily installed. The reinforcement connection uses straight thread sleeve connection, and the connection quality meets the requirements of the specifications.
[0035] During the installation and acceptance of the external formwork, the external formwork should also be evenly coated with release agent in advance. After the installation is completed, the overall verticality of the formwork should be checked and the error should be controlled within ±5mm.
[0036] Reinforce the bottom of the formwork with tension screws and mortar to ensure that the bottom of the formwork is well sealed and there is no risk of leakage.
[0037] Pour in 300mm layers to complete 1200mm to ensure the concrete is dense.
[0038] After the pouring is completed and the water is absorbed from the surface, spray the surface-drying retarder on the construction joint, and strictly control the spraying amount according to the product instructions.
[0039] Remove the tension screws at the bottom of the formwork, start lifting the formwork with a stroke of 40mm according to the retarding time determined by the trial mix, observe the state of the concrete emerging from the formwork, the concrete surface is smooth, without any scratches or cracks; check whether all devices in the system are normal and all components are running smoothly.
[0040] In conjunction with the steel bar installation acceptance speed, the template is intermittently slid up 1200mm to check the deflection and verticality of the template. The template deflection error is controlled within ±2mm, and the cylinder wall verticality error is controlled within ±5mm.
[0041] The construction joints are flushed with high-pressure water and inspected. The release agent is evenly applied to the construction joints and the inner wall of the formwork, and the internal and external hangers are installed. The construction joints are flushed clean and no debris is left.
[0042] Cast in 300mm layers for 1200mm and install internal and external hangers.
[0043] After the pouring is completed and the surface is hydrated, spray the surface-drying retarder on the construction joint. The formwork is intermittently slid 1200mm according to a stroke of 40mm to coordinate with the speed of acceptance of the installation of steel bars and embedded parts, and complete the installation of internal and external hangers. Keep all components in coordinated operation during the sliding process.
[0044] After the upper mold is poured and the water is absorbed from the pouring surface, the construction joint is sprayed with surface drying retarder, and the spraying amount is uniform.
[0045] The formwork is discontinuously slid up 1200mm with a stroke of 40mm. The speed of installation acceptance of steel bars and embedded parts is coordinated, and the formwork deflection and verticality of the cylinder wall are checked. The formwork deflection and verticality of the cylinder wall are checked every 400mm of sliding to ensure that the deviation is within the allowable range.
[0046] The construction joints shall be flushed with high-pressure water and the release agent shall be evenly applied to the construction joints and the inner wall of the formwork. The construction joints shall be inspected and accepted in time after flushing, and the release agent shall be applied immediately after passing the inspection.
[0047] The concrete pouring is completed in layers of 300mm each, and during the concrete pouring process, a dedicated person is assigned to check the formwork to prevent leakage.
[0048] After smoothing and trimming the original concrete slurry, the curing liquid is sprayed on it. The curing liquid is sprayed evenly to ensure that the concrete surface remains moist. This cycle is repeated until the chimney top is completed. The quality of each link is strictly controlled throughout the process to ensure that the outer wall of the chimney is of good quality and free of obvious defects.
[0049] The embodiments disclosed in the present invention are preferred embodiments, but are not limited to them. Ordinary technicians in this field can easily understand the spirit of the present invention based on the above embodiments and make different extensions and changes. As long as they do not deviate from the spirit of the present invention, they are all within the scope of protection of the present invention.
Claims
1. A construction method for lifting a high-grade concrete slide fixed mold, characterized in that: The method comprises the following steps: S1: Construction preparation, carry out the design of the slipform device. According to the plan layout form, cross-sectional dimensions, structural reinforcement, embedded parts design and configuration of the silo and cylinder wall structure, the factors of the structural opening setting and the load design combination method, and in accordance with the specifications and standards, design and review the design scheme of the hydraulic lifting system, formwork system and operating platform of the slipform device, and the lifting frame to form the sliding frame fixed form lifting system. After the design scheme is reviewed and approved, it will be processed and configured according to the design scheme; S2: Concrete mix design and trial mixing. The fineness modulus of the concrete sand should be medium-coarse sand above 3.
2. During the laboratory trial mixing stage, a 1m×1m×1m steel plate test box is used to simulate the actual mold bin and the layered pouring method to test the setting time of each layer. In addition, the construction plan is compiled and reviewed; S3: Acceptance of the installation of the slipform device, setting the reference axis and the inner and outer formwork edges and the gantry control line, checking and accepting the line setting, carrying out the acceptance of the installation of the first plate reinforcement, installing the fixed gantry, installing the formwork ring beam, installing the inner formwork, installing the main and secondary beams of the inner operating platform and the outer triangular platform, installing and debugging the support rods and jack hydraulic system, installing and accepting the vertical reinforcement of the cylinder wall extension, preliminarily installing the inner and outer hanger rods, installing and accepting the outer formwork, and completing the installation of the sliding frame fixed formwork system; S4: Normal sliding cycle. After the upper mold is poured, the surface drying retarder is sprayed on the construction joint after the water is absorbed from the pouring surface. The formwork is intermittently slid 900-1200mm with a stroke of 40mm. The speed of installation and acceptance of steel bars and embedded parts is coordinated. The formwork deflection and verticality of the cylinder wall are checked. The construction joint is flushed with high-pressure water and the construction joint and the inner wall of the formwork are evenly coated with release agent. The pouring is completed in 300mm layers for 900-1200mm. The surface of the original concrete slurry is smoothed and repaired, and then the curing liquid is sprayed on it. The cycle is repeated until the top of the cylinder is completed. S5: Dismantle the slipform device. After the cylinder top construction is completed, dismantle the slipform device.
2. A construction method for lifting a high-grade concrete slide fixed mold according to claim 1, characterized in that: In the above step S2, the retarding time of concrete is designed to ensure that no cold joints are formed at the junction of the upper and lower layers when the concrete is poured in layers, and that the demoulding strength of the first layer of concrete is 0.2MPa-0.4MPa when the formwork is lifted after the layered pouring of the entire slab is completed.
3. The construction method for lifting the fixed formwork of a high-grade concrete slide according to claim 1 is characterized in that: In the above step S3, it also includes reinforcing the tension screws at the bottom of the formwork and sealing with mortar, pouring 900-1200mm in 300mm layers, spraying surface-drying retarder on the construction joint after the pouring surface is water-absorbed, removing the tension screws at the bottom of the formwork, and starting to lift the formwork with a stroke of 40mm according to the retarding time determined by the trial mix, observing the state of the concrete removed from the formwork, checking whether the various devices in the system are normal, intermittently sliding 900-1200mm at the speed of steel bar installation acceptance, checking the deflection and verticality of the formwork, washing the construction joint with high-pressure water and accepting the construction joint, uniformly applying mold release agent on the inner wall of the formwork, installing internal and external hangers, pouring 900-1200mm in 300mm layers, installing internal and external hangers, spraying surface-drying retarder on the construction joint after the pouring surface is water-absorbed, and intermittently sliding the formwork 900-1200mm at a stroke of 40mm to cooperate with the speed of steel bar and embedded parts installation acceptance, and completing the installation of internal and external hangers.
4. A construction method for lifting a high-grade concrete slide fixed mold according to claim 3, characterized in that: Before the first full mold pouring, evenly apply the release agent to the formwork. After the pouring is completed, spray the surface retarder after the water is absorbed. During the small stroke intermittent lifting process, clean the formwork as you lift it.
5. The construction method for lifting the fixed formwork of a high-grade concrete slide according to claim 1 is characterized in that: In the above step S4, iron sheets with a thickness of 0.1 mm and a width of 300-500 mm are laid at the positive corners of the structure to isolate the sliding formwork and the solidified concrete at the corners from being disturbed and damaged.
6. The construction method for lifting the fixed formwork of a high-grade concrete slide according to claim 1 is characterized in that: In the above step S2, the sand used for concrete is expanded from natural river sand to machine-made sand. When machine-made sand is used, the content of stone powder below 0.15 mm in the screening test should be controlled below 10%.
7. The construction method for lifting the fixed formwork of a high-grade concrete slide according to claim 1 is characterized in that: In the above step S2, after the whole slab is poured layer by layer, the pouring resistance value of the first layer of concrete when the formwork is lifted is 0.30KN / cm 2 -1.05KN / cm 2 .
8. The construction method for lifting the fixed formwork of a high-grade concrete slide according to claim 5 is characterized in that: The iron sheet is adhered to the formwork by using sticky butter, and no release agent is applied to the concrete surface. When the formwork is lifted, the iron sheet adheres to the concrete surface by bonding force with the concrete surface and is removed after the concrete is demoulded.