Prefabricated composite floor slab construction method
Through the combination of prefabricated overlapping floor slab construction method and triangular steel truss structure, the problems of reliable connection and flatness in traditional construction are solved, efficient and economical floor slab construction is achieved, and the overall performance of the building is improved.
Patent Information
- Application Number
- CN202510572466.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-06
- Publication Date
- 2025-06-17
AI Technical Summary
Traditional prefabricated overlapping floor construction technology has a lack of reliable connection, integrity and load-bearing performance deviation, resulting in low construction efficiency and difficulty in forming a flat floor surface.
The prefabricated overlapping floor slab construction method is adopted to adjust its height and position by setting up the overlapping floor slab structure to ensure flat lifting; triangular steel bar truss overlapping floor slabs are used to assemble them in combination with L-shaped screws and angle steel to increase the stiffness and seismic resistance of the floor slabs.
It improves the flatness and connection performance of the floor slabs, shortens the construction cycle, reduces costs, and enhances the integrity and seismic resistance of the building.
Smart Images
Figure CN120159151A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of building structure construction, and specifically to a construction method for precast composite floor slabs. Background Art
[0002] With the development of building industrialization, prefabricated buildings have gradually become the mainstream trend in the construction industry due to their high efficiency and environmental protection characteristics. As an important part of prefabricated buildings, the construction quality of precast composite floor slabs directly affects the integrity of the building.
[0003] At present, the construction technology of precast composite floor slabs has been widely applied in various buildings such as residential buildings and office buildings. However, the floor slab systems that can be industrially manufactured are lackluster. Therefore, it also restricts the effective promotion of prefabricated steel structure houses. Moreover, there is a lack of reliable connections in traditional precast structure construction, and the integrity and bearing performance are poor. The surfaces at the junctions of concrete structure beams, walls and floor slabs or upper structure concrete are uneven, and traditional composite floor slabs cannot be laid, resulting in construction efficiency. Summary of the Invention
[0004] 1. Technical Problems to be Solved To solve the above technical problems, the present invention provides a construction method for precast composite floor slabs.
[0005] (2) Technical Solutions Based on this, the present invention provides the following technical solutions: A construction method for precast composite floor slabs, and the specific construction method is as follows: Step S1: Installation preparation, perform base cleaning and line marking. Clean the visible formwork residues on the surface of the precast components. The surveyor releases the horizontal control line and makes marks, and uses this to control the installation height and position of the floor bearing plate. At the same time, the control line is rechecked. The specific operation of installation preparation is: According to the construction drawings, check the types of composite slab components, determine the installation positions, and number the hoisting sequence of the composite slabs. The stacking of each stack of floor bearing plates should not exceed 6 pieces. The layers should be leveled, and the spacer timbers should be in a straight line. When placed against, it should be placed along the stress direction; Step S2: Support system erection, determine the setting position of the starting support point according to the structure of the composite floor slab, the erection length of the side support, and the load analysis. When the lapping length between the composite slab and the support ≥ 40mm, it is not necessary to separately support the area within 1.5m of the floor slab side support. When the lapping length between the composite slab and the side support is less than 35mm, a support system is set within the range of 0.2m near the floor slab side support; Step S3: Hoisting of the composite slab structure. When hoisting the composite slab structure, the four lifting points are evenly stressed, and the hoisting is slow to ensure the smooth hoisting of the composite slab; Step S31: The center of gravity of the lifting appliance and the component coincides vertically, and the horizontal angle between the sling and the lifting beam is not less than 60 degrees. Conduct numerical calculations for the lifting of the composite slab before hoisting. When the length of the component exceeds 4m, use a modular lifting beam for hoisting; Step S32: During the hoisting process of the composite slab, make a slight pause 500mm above the working layer, and adjust the direction of the composite slab according to its position for positioning. During the hoisting process, pay attention to avoiding the collision between the reserved steel bars on the composite slab and the vertical steel bars of the wall. Slowly lower and place the composite slab to avoid excessive impact during hoisting and placement, which may cause damage to the slab surface; Step S33: After the composite slab is installed in place, use the adjustable support under the slab to adjust the elevation of the bottom slab of the precast composite slab. After the position of the bottom slab of the precast composite slab is adjusted, remove the tower crane hook; Step S4: Connect the floor deck. Lift the composite floor structure through the lifting points set at the composite floor slab structure and adjust it horizontally. Place it along the center line of the beam or wall, slowly lower it and adjust the position to align the exposed steel bar truss with the center line of the beam or wall; Step S5: Laying of water and electricity pipelines. Lay pipelines in the building. Use rigid pipelines for straight-through laying and pipes with better flexibility for diagonal laying; Step S6: Binding of steel bars for the composite slab. Bind steel bars according to the steel bar spacing control line above the composite slab. The connecting steel bars need to be set at the disconnection of the steel bar truss floor deck on the beam. Use web bars of the same specification, grade, and model to fixedly connect the steel bars at the disconnection of the upper chord steel bar and the lower chord steel bar of the steel bar truss. When binding the steel bars of the composite slab, temporary supports can be added at the bottom end of the composite slab; Step S7: Concrete pouring; Step S8: Removal of supports. First remove the supports under the slab, then remove the supports under the beam, and finally remove the cantilever supports.
[0006] Preferably, the composite floor slab structure is composed of a triangular steel bar truss composite floor slab, angle steel, L-shaped screw rods, and nuts, and the composite floor slab is assembled by L-shaped screw rods.
[0007] Preferably, one side of the angle steel is grooved and the L-shaped screw rods are prefabricated in the factory, and the steel bar truss composite floor slab is prefabricated in the processing factory. Holes of the same size are reserved at the corresponding positions of the composite slab and the angle steel holes for the screw rods to pass through. Before leaving the factory, the steel bars of the floor deck are pre-bound and poured, and holes are reserved in the width direction of the beam, and holes are also pre-opened at the corresponding angle steel positions.
[0008] (III) Beneficial effects Compared with the prior art, the present invention provides a construction method for precast composite floor slabs, which has the following beneficial effects: The construction method of the precast composite floor slab can adjust the height and position of the composite floor slab by setting up a composite floor slab structure, solve the problems caused by the uneven surface of the beam or wall, ensure the flatness of the floor slab after hoisting, and adjust the relative position of the composite floor slab and the beam or wall. This can avoid additional costs of personnel, materials and machinery due to quality problems. At the same time, the use of a triangular steel bar frame for the composite floor slab results in a fast assembly speed, which can effectively reduce the construction period. Moreover, the triangular frame composite floor slab itself has good overall performance and stiffness, and has good seismic performance, and can be applied to steel structures. The composite layer is placed under the upper flange of the steel beam, and part of the steel beam is hidden in the floor slab, saving construction space, improving construction efficiency, increasing the connection performance between the floor slab and the beam and wall. And sintered hollow bricks are used as filling blocks between the rib beams to reduce the self-weight of the floor slab, and the exposed binding bars on the upper part of the steel bar truss are used to strengthen the bond of the composite surface, so that the precast layer and the cast-in-place layer can form a whole to exert the cooperative working performance, and at the same time, it can also ensure the integrity of the floor slab and the stiffness in the plane. Description of the Drawings
[0009] Figure 1 It is the layout diagram of the hoisting sequence of the composite slab of the household type of the present invention; Figure 2 It is the hoisting schematic diagram of the present invention; Figure 3 It is the connection schematic diagram of the angle steel and the screw rod of the present invention; Figure 4 It is the schematic diagram of the support structure of the composite floor slab structure of the present invention; Figure 5 It is the schematic diagram of the composite floor slab structure of the present invention; Figure 6 It is the schematic diagram of the hollow brick structure of the present invention; Figure 7 It is the assembly schematic diagram of the composite floor slab structure of the present invention.
[0010] In the figure: 1. Composite floor slab structure; 11. Angle steel; 12. L-shaped screw rod; 13. Hollow brick; 2. Hoisting beam; 3. Suspension cable; 4. Concrete precast block; 5. Steel bar truss; 51. Web bar; 52. Upper chord bar; 53. Lower chord bar; 6. Side support. Detailed Embodiments
[0011] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.
[0012] Example 1 The construction method of the precast composite floor slab is as follows: Installation preparation: Clean the base and draw lines. Clean the visible formwork residues on the surface of the composite floor slab structure 1. The surveyor releases the horizontal control line and makes marks to control the installation height and position of the composite floor slab structure 1. At the same time, review the control line. The specific operation of installation preparation is as follows: According to the construction drawings, check the component types of the composite floor slab structure 1, determine the installation positions, and number the hoisting sequences of the composite floor slab structure 1 in each building. The hoisting sequences of the composite floor slab structure 1 in each building are as Figure 1 shown. The stacking of each stack of the composite floor slab structure 1 should not exceed 6 pieces. Pad it flat between layers, and the spacer timbers should be in a straight line. When placing it against a wall, place it along the stress direction; Support system erection: Determine the setting position of the starting support point according to the erection length between the composite floor slab structure 1 and the side support 6 and the load analysis. When the lapping length between the composite floor slab structure 1 and the support is ≥ 40mm, it is not necessary to separately support the area within 1.5m of the side support 6 of the floor slab. When the lapping length between the composite floor slab structure 1 and the side support 6 is less than 35mm, a support system is set within the range of 0.2m near the side support 6. During the construction process of the floor slab support system, control and correct the horizontal height of the support system through measuring instruments. After erection, conduct acceptance to ensure that the stiffness, strength, and stability of the support system meet the acceptance standards to ensure the flatness of the ceiling of the floor slab casting. When the floor slab span > 4m, make appropriate cambers according to the calculated deflection; Hoisting of the composite floor slab structure 1: When hoisting the composite floor slab structure 1, the four lifting points are evenly stressed, and hoist slowly to ensure the stable hoisting of the composite slab; The hoisting tool and the center of gravity of the component coincide vertically. The horizontal angle between the sling 3 and the hoisting beam 2 is not less than 60 degrees. Conduct hoisting numerical calculation on the composite floor slab structure 1 before hoisting. When the component length exceeds 4m, use a modular hoisting beam for hoisting. The hoisting schematic diagram is as Figure 2 shown; During the hoisting process of the composite floor slab structure 1, make a slight pause at 500mm above the working layer, adjust the direction of the composite floor slab structure 1 according to its position for positioning. During the hoisting process, pay attention to avoiding the collision between the reserved steel bars on the composite floor slab structure 1 and the vertical steel bars of the wall. Slowly place the composite floor slab structure 1 steadily to avoid excessive impact force during hoisting and placement, which may cause damage to the slab surface; After the composite floor slab structure 1 is installed in place, adjust the floor elevation of the precast composite floor slab structure 1 using the adjustable support under the slab. After the position of the bottom slab of the composite floor slab structure 1 is adjusted, remove the tower crane hook; When connecting with the composite floor slab structure 1, during actual construction, it is difficult for the angle steel 11 and the L-shaped screw rod 12 to bear the self-weight of the composite floor slab structure 1, and it is not convenient for adjustment and assembly. Therefore, during actual construction, the steel bar trusses 5 on both sides of the exposed part of the composite floor slab structure 1 are exposed. Concrete precast blocks 4 are placed at the side supports 6 and are fixedly carried on the beam or wall through the steel bar trusses 5 at both ends. The composite floor slab structure 1 is lifted by the lifting points set at the composite floor slab structure 1 and adjusted horizontally, placed along the center line of the beam or wall, slowly lowered and adjusted in position to align the exposed steel bar trusses 5 with the center line of the beam or wall; Place the concrete precast block 4 at the side support 6, pass the L-shaped screw rod 12 through the reserved hole of the angle steel 11, fix the horizontal bar of the L-shaped screw rod 12 on the upper part of the concrete precast block 4, and tighten and fix the vertical bar of the L-shaped screw rod 12 with a nut. The connection of the L-shaped screw rod 12 with the angle steel 11 and the composite floor slab structure 1 is as Figure 3 shown; For the laying of hydropower pipelines, provide the point layout diagrams of all systems according to the reserved embedments on the composite floor slab structure 1 required by the specialty. Use BIM technology to deepen the reserved embedment points and combine them with the layout of the composite floor slab structure 1, adjust the conflicting steel bar trusses 5 and bottom bars of the slab, send the deepened drawing to the processing factory, and reserve and embed the corresponding reserved holes and hydropower wire box points, etc. during the processing and production of the composite floor slab structure 1 according to the deepened design drawing. During the shipping and installation process, it is necessary to protect their finished products; During the on-site construction process, lay and connect the mechanical and electrical and hydropower pipelines in the composite slab part according to the content of the deepened drawing. When laying pipelines in the building, use rigid pipelines for straight-through penetration and pipes with better flexibility for oblique penetration. Avoid bundling and embedding multiple pipelines. Use pipelines with a smaller diameter and disperse the perforation and embedding. During the construction process, all parties must do a good job in protecting the finished products. The mechanical and electrical wire boxes and pipelines in the composite floor slab structure 1 are arranged with mechanical and electrical pipelines according to the requirements of the deepened design drawing; For the steel bar binding of the composite floor slab structure 1, carry out steel bar binding according to the steel bar spacing control line above the composite floor slab structure 1. The connecting steel bars need to be set at the disconnection of the steel bar truss floor slab on the beam. Use the web bars 51 of the same specification, grade, and model to fixedly connect the steel bars at the disconnection of the upper chord bar 52 and the lower chord bar 53 of the steel bar truss 5. The additional negative moment steel bars are additional upper negative moment steel bars added at the floor slab support beam. It is necessary to bind and connect the connecting steel bars with the additional negative moment steel bars and the chord bars of the steel bar truss 5. To ensure the thickness of the upper steel bar protection layer, the truss steel bars 5 of the composite floor slab structure 1 can be used as the stirrups for the upper steel bars. The support structure of the composite floor slab structure 1 is as Figure 4 shown; Concrete pouring: Before concrete pouring, the installation of the composite floor slab structure 1 and on-site steel bar binding and other items shall be inspected and accepted in accordance with relevant specifications. Positioning fixtures shall be used to check and correct the exposed steel bars of precast components. Before pouring concrete, wrap the exposed part of the inserted steel bars with tape to avoid contaminating the steel bar joints during concrete pouring. To ensure uniform stress on the bottom plate and supports of the precast composite slab, concrete pouring shall be carried out from the middle to both sides. Control the in-mold temperature before concrete pouring. The concrete pouring shall be continuously constructed and completed at one time. Use a flat vibrator to vibrate to make the air bubbles in the concrete overflow and ensure dense vibration. When pouring concrete at the connection between the composite component and the surrounding cast-in-place concrete structure, the vibration points shall be densified to ensure the vibration quality of the concrete in the structural part. When pouring concrete, pay attention not to move the position of the embedded parts and do not contaminate the exposed connection parts of the embedded parts. When pouring concrete, avoid excessive local concrete stacking; Support removal: The number of supports configured for each building is 3 floors. The removal of the support rods shall comply with the concrete strength requirements for the removal of the bottom formwork in the "Code for Construction Quality of Concrete Structures GB50204-2002". Determine the formwork removal time of the support rods according to the reserved formwork removal test blocks. Generally, the bottom formwork of the slab is removed after 10 days, the bottom formwork of the beam is removed after 14 days, and the cantilever support is removed after 28 days. When removing each support, hold the support rod with one hand and use a hammer to loosen the adjustable fulcrum in the hammering direction with the other hand to remove the support rod.
[0013] In some embodiments, the composite floor slab structure 1 is composed of angle steel 11, L-shaped screw rods 12, hollow bricks 13, and steel bar trusses 3. The composite floor slab is assembled by the L-shaped screw rods 12. One side of the angle steel 11 is grooved and the L-shaped screw rods 12 are prefabricated in the factory. The steel bar truss composite slab 1 is prefabricated in the processing factory. Holes of the same size are reserved at the corresponding positions of the composite floor slab structure 1 and the angle steel holes to facilitate the penetration of the L-shaped screw rods 12. Before leaving the factory, the composite floor slab structure 1 and the hollow bricks 13 are pre-assembled and the pouring is completed. The width of the hollow bricks 13 is 183 mm, the compressive strength is 2.84 MPa, and the flexural strength is 2.00 MPa. Using the hollow bricks 13 to replace concrete as the filling material for the composite floor slab structure 1 not only improves the bearing capacity but also reduces the overall mass of the composite floor slab structure 1. Using sintered hollow bricks as the filling blocks between the rib beams to reduce the self-weight of the floor slab, pre-reserve holes in the width direction of the beam, and at the same time pre-open holes at the corresponding position of the angle steel 11. The schematic diagram of the composite floor slab structure 1 is as Figure 5 shown, and the structure of the hollow bricks 13 is as Figure 6As shown in the figure. During on-site construction, the precast concrete block 4 is installed at the side support 6, exposing the steel bar trusses 3 on both sides of the composite floor slab structure 1. The precast composite floor slab structure 1 is fixed to the structural beam or wall through the steel bar trusses 3 exposed at both ends, and the side with holes of the angle steel 11 fits tightly with the precast slab. During on-site assembly, the composite floor slab structure 1 is placed on the pre-fixed support frame, and it is fixed by passing the L-shaped screw rod 12 through the reserved holes of the beam and the angle steel 11. The cross bar of the L-shaped screw rod 12 is supported by the beam or wall, and the bottom of the vertical rod of the L-shaped screw rod 12 is fixed and tightened with nuts. At this time, the combination bolts are placed on the wall or beam to play a role in stable adjustment. The height difference at the four corners of the composite floor slab is adjusted by loosening or tightening the bottom nuts until the same horizontal height is reached, achieving a close-fitting effect between the slabs. The overall assembly schematic diagram is as shown in Figure 7 shown.
[0014] Embodiment 2 Taking the first-phase Cyberspace Security Research Building and College Building II project of Beijing University of Posts and Telecommunications in Shahe Campus, located in the Higher Education Park of Shahe Town, Changping District, Beijing, including 3 office teaching buildings and an underground garage, with a total construction area of approximately 37475 m 2 . Taking the example that the steel structure is adopted in the corridor part and the floor slab is the composite floor slab structure 1 of the present invention, replacing the original cast-in-place formwork system for the top slab; Adopting the precast composite floor slab construction method of the present invention can improve the construction efficiency, reduce the input of installation personnel, shorten the installation and commissioning period, save costs, and have significant economic benefits. Compared with the traditional composite slab construction process, the installation and commissioning time is reduced, and 1.5 days can be saved for each construction flow section. Compared with the traditional cast-in-place slab, the cost is saved by 500,000 yuan in total. Good results have been achieved in engineering applications.
[0015] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A prefabricated composite floor construction method, characterized in that: The specific construction methods are as follows: Step S1: Preparation for installation, cleaning the base layer and marking the lines, cleaning the visible template residues on the surface of the prefabricated parts, and controlling the installation height and position of the floor deck; Step S2: support system installation, determine the location of the starting support point according to the installation length of the composite floor structure and the side support and load analysis; Step S3: hoisting the composite floor structure. When the composite floor structure is hoisted, the four hoisting points are evenly stressed; Step S4: connecting the composite floor structure, lifting the composite floor structure through the lifting points set at the composite floor structure and adjusting the horizontal direction, placing it along the center line of the beam or wall, slowly lowering it and adjusting its position; Step S5: Laying of water and electricity pipelines: Laying pipelines in the building, using rigid pipelines for straight penetration and flexible pipes for oblique penetration; Step S6: tying the steel bars of the composite floor structure, tying the steel bars at the steel bar spacing control line above the composite floor structure, setting the connecting steel bars at the disconnection of the steel bar truss floor deck on the beam, and using the web bars to fix and connect the steel bars at the disconnection of the upper chord steel bars and the lower chord steel bars of the steel bar truss; Step S7: concrete pouring; Step S8: Support removal: first remove the slab bottom support, then remove the beam bottom support, and finally remove the cantilever support.
2. The method for constructing a prefabricated composite floor according to claim 1, characterized in that: As described above, in step S1, the specific operations of installation preparation are: according to the construction drawings, check the type of composite floor structure components, determine the installation position, and number the composite floor structure hoisting sequence. The number of stacked floor decking plates should not exceed 6, the layers should be leveled, the pads should be in a straight line, and placed along the force direction when leaning.
3. The method for constructing a prefabricated composite floor according to claim 1, characterized in that: As described above in step S3, the specific operation of lifting the composite floor structure is as follows: Step S31: The center of gravity of the sling and the component coincide in the vertical direction, and the horizontal angle between the sling and the lifting beam is not less than 60 degrees; Step S32: During the hoisting process of the composite floor structure, pause 500 mm above the working layer, and adjust the direction of the composite floor structure according to the position of the composite board for positioning; Step S33: After the composite floor structure is installed in place, the elevation of the bottom plate of the prefabricated composite floor structure is adjusted by using the adjustable support under the plate.
4. The method for constructing a prefabricated composite floor according to claim 3, characterized in that: The sling adopts a first-class sling type: 18mm6×V24FC-FC type steel wire rope.
5. The method for constructing a prefabricated composite floor according to claim 1, characterized in that: As described in step S2, when the overlap length between the composite floor structure and the edge support is ≥40mm, there is no need to provide separate support within 1.5m of the edge support of the composite floor structure. When the overlap length between the composite floor structure and the edge support is less than 35mm, a support system is set up within 0.2m near the edge support of the composite floor structure.
6. The method for constructing a prefabricated composite floor according to claim 1, characterized in that: The composite floor structure is composed of angle steel, L-shaped screw rod, hollow brick and steel truss. The composite floor is assembled by L-shaped screw rod. The slotted holes on one side of the angle steel and the L-shaped screw rod are prefabricated in the factory. The steel truss composite plate is prefabricated in the processing plant. Holes of the same size are reserved at the corresponding positions of the composite floor structure and the angle steel holes to facilitate the insertion of the L-shaped screw rod. The composite floor structure and the hollow brick are pre-assembled and cast before leaving the factory. The width of the hollow brick is 183 mm, the compressive strength is 2.84 MPa, and the flexural strength is 2.00 MPa.
7. The method for constructing a prefabricated composite floor according to claim 6, characterized in that: The slotted holes on one side of the angle steel and the L-shaped screw rod are prefabricated in the factory, the composite floor structure is prefabricated in the processing plant, holes of the same size are reserved at the corresponding positions of the composite floor structure and the angle steel holes, the composite floor structure and the hollow bricks are pre-assembled and cast before leaving the factory, holes are pre-reserved in the width direction of the beam, and holes are pre-drilled at the corresponding angle steel positions.