Method for preventing and treating common problems of building construction quality

Abstract

The invention belongs to the technical field of building construction, and particularly relates to a method for preventing and treating common quality faults of building construction, which comprises the following steps: step S1, dividing common quality faults occurring in the building construction process into four conditions of concrete floor cracks, displacement of embedded steel bars in walls and columns, roof leakage and wall cracks; s2, corresponding prevention and control measures are designed for common quality problems occurring in the four types of building construction processes; and S3, according to the design of each type of prevention and control measures, prevention and control construction of various common quality faults is conducted. Common quality problems are clearly divided into four types of concrete floor cracks, displacement of embedded steel bars in walls and columns, roof leakage and wall surface cracks, then an exclusive prevention and treatment process is designed for each type of common problems, the defect that existing measures are cut at a time is overcome, various common quality problems in the building construction process are effectively prevented and treated, the building construction quality is improved, and the construction period is shortened. And repeated reworking is avoided, the construction efficiency is improved, the construction period is shortened, and the method is suitable for application and popularization.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of building construction, and particularly relates to a method for preventing and treating common quality problems in building construction. BACKGROUND

[0002] In the field of building engineering construction, especially in public building projects involving multiple buildings and multiple structural forms (such as frame structure and shear wall structure), the project is characterized by large scale, multiple construction links and high technical requirements. Such projects usually have large occupation area, large total building area, cover multi-story buildings and underground structures, include multiple professional construction links such as reinforcement engineering, formwork engineering, concrete engineering, waterproof engineering and secondary structure engineering, and have great difficulty in connection and quality control between links.

[0003] From the current overall situation of building construction, the existing quality control measures have many deficiencies when adapting to such complex projects, especially for large public buildings, which have higher requirements for structural safety, durability and use comfort. However, the existing technology does not fully consider the special needs of such projects, such as not strengthening floor load control to avoid safety hazards in later use, not optimizing waterproof measures to ensure dry and comfortable public environment, resulting in various use problems after the building is delivered, increasing the cost and difficulty of later maintenance. SUMMARY

[0004] The application provides a method for preventing and treating common quality problems in building construction, which is suitable for complex EPC projects, covers key construction links, has a closed loop process and quantified parameters.

[0005] The application also provides a method for preventing and treating common quality problems in building construction, comprising the following steps: Step S1: classifying common quality problems occurring in the building construction process into four categories: concrete floor cracks, wall and column embedded steel displacement, roof leakage and wall cracks; Step S2: designing corresponding prevention measures for the four types of common quality problems occurring in the building construction process, and the prevention measures need to meet the requirements of the construction design drawings of the project; Step S3: according to the design of each type of prevention measure, carrying out prevention construction of each type of common quality problem, and keeping key process acceptance records during construction, which need to be signed and confirmed by the technical responsible person of the construction unit and the supervising engineer.

[0006] To better implement the method of the application, further, in step S3, the process of prevention construction for concrete floor cracks occurring in the building construction process is: Step S311: Perform written technical disclosure to the construction team, and clearly define the operation parameters, quality standards and acceptance requirements of each step. The disclosure content includes template support calculation data, concrete mix ratio, curing method, load limit value; the disclosure record is signed and confirmed by the discloser and the disclosed person, and is kept for archiving; step S312: Design the template support system according to the design thickness of the concrete floor and the construction live load; wherein the vertical rod adopts Φ48x3.5mm steel pipe, the vertical rod spacing is not greater than 1.5m, the horizontal rod step distance is not greater than 1.8m, the main keel adopts 100x100mm wood square, the secondary keel adopts 50x100mm wood square and the spacing is not greater than 300mm; ensure that the rigidity of the support system is not less than 1.2 times of the total load of the upper part, and the strength is not less than 1.1 times of the total load of the upper part; when erecting, the bottom of the vertical rod is paved with 50mm thick wood footboard, the footboard is paved with 100mm thick gravel cushion under the footboard, the vertical rod and the horizontal rod are rigidly connected by right angle fasteners, and an adjustable support is arranged at the top of each vertical rod, the length of the support screw rod extending out of the top of the steel pipe is not greater than 200mm; Step S313: Control the concrete water-cement ratio not greater than 0.55, the sand ratio 35%-40%, and the slump 120mm±20mm according to the design concrete strength grade of the floor; use weight ratio measurement when mixing concrete, and the interval time from mixing concrete to pouring completion is not greater than 120min; before pouring, check the floor reinforcement mesh, and use Φ12mm steel reinforcement stool to support the upper iron reinforcement; pour by layers during pouring, and the thickness of each layer is not greater than 500mm, use high-frequency vibrating rod for vibration, and the vibration point spacing is not greater than 400mm, until the concrete surface has no obvious bubbles escaping and appears floating slurry; Step S314: Start curing within 12h after concrete pouring: when the environmental temperature is greater than 5℃, cover the geotextile and spray water for curing, the spraying frequency is every 2h-3h, keep the geotextile wet, and the curing time is not less than 7 days; when the environmental temperature is not greater than 5℃, cover the fire-retardant insulation quilt combined with electric heat tracing for curing, the electric heat tracing temperature is controlled to be 5-15℃, and the curing time is not less than 14 days; walking or piling up sundries on the floor is prohibited during the curing period; Step S315: No load is allowed to be applied within 12h after concrete pouring; after 12h, if building materials need to be piled up, the dispersed piling up method is adopted, the single piling area is not less than 0.3m 2 , the piling strength is not greater than 80% of the design live load of the floor, and the piling height is not greater than 1.2m; avoid standing in the same position for a long time when operating, and strictly prohibit dragging heavy tools with a weight greater than 50kg on the floor; Step S316: before template removal, take the concrete test block under the same curing condition to carry out the compressive strength test, when the strength of the test block reaches 75% or more of the design concrete strength grade of the floor, the template can be removed; the removal sequence is to remove the secondary keel first, then the main keel, then the horizontal rod, and finally the vertical rod, and strong prying and hard separation are prohibited; the removed template and supporting parts are classified and stacked to the floor area that has reached the design strength, and the stacking load is not greater than 1.0 kN / m 2 ; after the template is removed, the floor surface is inspected, if the width of the micro crack is not greater than 0.2 mm, the epoxy resin slurry is used for injection sealing, if the crack width is greater than 0.2 mm, a special treatment scheme needs to be formulated, and the implementation is confirmed by the design unit.

[0007] In order to better realize the method of the application, further, in the step S312, after the template supporting system is erected, a uniform load of 2.0 kN / m 2 is used for pre-pressing, the pre-pressing time is not less than 24 h, the vertical rod settlement after pre-pressing is not greater than 10 mm, and there is no obvious deformation, so that the next process can be entered.

[0008] In order to better realize the method of the application, further, in the step S313, when the concrete is mixed, 3% to 5% of the cement quality of the I-grade fly ash is mixed, the fly ash water demand ratio is not greater than 100%, and the loss on ignition is not greater than 5%, so as to reduce the dry shrinkage rate of the concrete.

[0009] In order to better realize the method of the application, further, in the step S314, when the environmental temperature is greater than 30 DEG C, a sunshade net is additionally arranged above the geotextile to avoid the direct sunlight to cause the water in the concrete surface to evaporate too fast.

[0010] In order to better realize the method of the application, further, in order to better realize the method of the application, further, in the step S315, a load warning mark is arranged on the floor to mark the allowed stacking area and the stacking limit value, a full-time safety officer inspects once every 2 h, records the load stacking condition and keeps the inspection record.

[0011] In order to better realize the method of the application, further, in the step S316, after the template is removed, the floor surface is inspected, if the width of the micro crack is not greater than 0.2 mm, the epoxy resin slurry is used for injection sealing, if the crack width is greater than 0.2 mm, a special treatment scheme needs to be formulated, and the implementation is confirmed by the design unit and a written opinion is issued, and the treatment record is kept and filed.

[0012] In order to better realize the method of the application, further, in the step S3, the process of preventing and treating the displacement of the embedded steel bars in the middle wall and the column is as follows: Step S321: the on-site remaining steel rod head with a diameter not less than Φ16 is used to process the wall and column steel reinforcement positioning frame: the frame column positioning frame is made according to the column section size, the positioning frame is consistent with the column main reinforcement design interval, and one is arranged at the position 1.0 m away from the floor surface and the upper opening of the formwork; the positioning frame of the shear wall door and window opening hidden column is made according to the design size of the opening, the positioning frame is fixed with the hidden column main reinforcement, and is arranged at the position 20 cm~30 cm away from the top of the plate; the wall body distributed steel reinforcement positioning frame adopts an inner top and outer clamping type structure, the frame body horizontal reinforcement slot interval is matched with the wall body vertical reinforcement design interval, and is installed at the position 2 cm~3 cm away from the top of the wall and is embedded in the wall formwork; the both ends of all the positioning frames are processed to have a 10 cm connecting section, and adjacent positioning frames are connected through Φ8 steel reinforcement welding; Step S322: the wall and column main reinforcement is bound and fixed with the upper and lower reinforcement of the bottom plate, each reinforcement binding point is not less than 3, and Φ12 additional steel reinforcement is additionally arranged within the range of 500 mm of the root of the reinforcement, the additional steel reinforcement is welded and fixed with the bottom plate reinforcement; before concrete pouring, the verticality of the wall and column reinforcement is rechecked by using a theodolite, if deviation is found, the deviation is slowly adjusted by using a 1:6 slope, and forced bending is prohibited; Step S323: when the concrete is poured, a full-time reinforcement worker is arranged to stand by, a vibrating rod is used for vibration, and direct collision of the vibrating rod with the reinforcement is avoided; after 300 mm height of concrete is poured, the position of the reinforcement is rechecked once, if displacement occurs, pouring is immediately stopped, and the displaced reinforcement is treated by using a spacer reinforcement welding method: the spacer reinforcement has the same diameter as the main reinforcement, the II grade steel spacer reinforcement is welded on two surfaces of the main reinforcement, and the I grade steel spacer reinforcement is welded on two surfaces of the main reinforcement, after the treatment is completed, the supervision unit is checked and accepted, and signature confirmation is made before pouring is continued; Step S324: the position of the wall and column reinforcement is rechecked within 24 hours after the concrete is poured, the displacement condition and treatment measures are recorded, a wall and column reinforcement displacement monitoring record table is formed, and the table is kept and filed after signature confirmation of the construction unit technical person in charge and the supervision engineer.

[0013] In order to better realize the method of the application, further, the process of the roof leakage prevention and treatment construction in step S3 is: Step S331: determine the position of the roof water outlet according to the design requirements, the slope layer is laid with 1:8 volume ratio of cement perlite, and the slope is not less than 2%; when the slope layer is constructed, a control point is set every 2m to ensure that the flatness deviation of the slope layer surface is not more than 5mm / m; after the slope layer is maintained for 7 days, the water test is carried out, and whether the drainage is smooth or not is observed, and no water accumulation phenomenon can enter the next process, and the water test image is recorded; step S332: at the gutter, eave gutter, eave, deformation joint, water, penetrating waterproof layer pipe opening and water outlet, a 3mm thick SBS modified asphalt waterproof roll material is laid as an additional layer, and the additional layer roll material and the base layer are constructed by full adhesion method; the additional layer roll material at the pipe opening should wrap the pipe circumference, and the roll material closing end is fixed by a metal hoop, and the surface of the metal hoop is coated with anti-rust paint; step S333: the waterproof layer is made of 4mm thick SBS modified asphalt waterproof roll material, and the laying direction is parallel to the roof slope, and the long side lap width is not less than 100mm, and the short side lap width is not less than 150mm; when the roll material is laid, the hot air welding machine is used to heat the lap joint to ensure that the lap joint is fused and bonded, and after bonding, the lap joint is checked by a craft knife, and no delamination phenomenon is qualified; the end of the vertical surface roll material is embedded into the pre-set groove of the vertical wall, the groove is filled with polyurethane sealant, and the fullness of the sealant is not less than 90%; step S334: the pipe opening penetrating the waterproof layer is sealed by C30 fine stone expansion waterproof impermeable concrete in two times: the first sealing is to the pipe diameter 1 / 2, and the second sealing is to the roof slope layer elevation after 3 days of maintenance, and the two sealings should be vibrated and compacted; after the waterproof layer is constructed, 24h water storage test is carried out, and after no leakage is observed, the roof water storage test record is filled, and the construction unit, the supervision unit and the construction unit jointly sign and confirm to be stored and filed.

[0014] In order to better realize the method of the application, further, the process of preventing and treating the wall crack in step S3 is: Step S341: according to the design mortar strength grade, the weight ratio is measured and mixed; when mixing, 0.3% of the mass of cement is mixed into the mortar thickening agent to improve the workability of the mortar, the mortar is used within 3 hours after mixing, and the mortar beyond the initial setting time is prohibited; step S342: the filler wall is made of MU10 autoclaved aerated concrete block, and the block is wetted 1-2 days before being built: the moisture content of common bricks, hollow bricks and perforated bricks needs to reach 10%-15%, the moisture content of lime sand bricks and fly ash bricks needs to reach 8%-12%, and there is no obvious water accumulation on the surface after watering; before building, the wall length and block size are drawn to draw the arrangement diagram, the skin number rod is set, and the mortar joint thickness is marked on the skin number rod, wherein the horizontal mortar joint is 15mm±2mm, and the vertical mortar joint is 20mm±2mm; when building, the one-order and one-ding group building method is used, and the up-down skin block staggered joint length is not less than 1 / 3 of the block length; step S343: the filler wall and the concrete column, wall connection part are provided with Φ6@500 tie bars, the tie bars extend into the wall by not less than 1000mm, and the end is bent by 90°; the tie bars are fixed by the way of planting, the drilling diameter is Φ8mm, the hole depth is not less than 10 times the diameter of the tie bar, the planting glue is the epoxy-based adhesive, and the tie bars are maintained for 7 days after planting, the pulling test is carried out, and the pulling test record is kept after being signed by the supervising engineer; step S344: the filler wall is plastered 7 days after building, the plastering is divided into two layers: the bottom layer plastering thickness is 8-10mm, the surface layer plastering thickness is 5mm-7mm, and the interval time between the two layers of plastering is not less than 24h; before plastering, 400mm wide alkali-resistant mesh cloth is pasted at the interface of different materials, and the mesh cloth overlap width is not less than 100mm; within 24h after plastering, the earthwork cloth is covered and watered, the maintenance time is not less than 7 days, the watering frequency is not less than 3 times a day, and the plastering surface is prohibited from being collided during the maintenance period.

[0015] Compared with the prior art, the present application has the following advantages and beneficial effects: (1) The quality common problems are clearly divided into four categories: concrete floor cracks, wall and column embedded steel displacement, roof leakage and wall cracks, and a special prevention process is designed for each type of common problem to avoid the drawbacks of one-size-fits-all existing measures, effectively prevent various quality common problems in the building construction process, improve the building construction quality, avoid repeated rework, provide construction efficiency, and shorten the construction period; (2) The key construction parameters are quantified, the formwork stand rod spacing, concrete water-cement ratio, low temperature curing temperature and the like are clearly defined in the concrete floor crack prevention, to ensure that the formwork support stiffness and the concrete performance meet the standards; in the wall crack prevention, the watering standards of common bricks and lime sand bricks are distinguished, the mesh cloth overlap width is clearly defined, and the construction deviation caused by ambiguous parameters is avoided; in the roof waterproofing, the long edge overlap width of the roll material and the pipe port plugging concrete impermeability grade are specified to ensure that the waterproof effect is durable and reliable; (3) The method introduces whole-process management and control of technical disclosure, process monitoring, acceptance record and archiving, forms a management and monitoring system of play arrangement, and clearly determines operation parameters through written disclosure before construction, and the disclosure person and the disclosed person sign and confirm; during construction, measures are implemented through on-site personnel, and the implementation is ensured through regular inspection; after construction, key records are retained, and the construction unit technical person and the supervision engineer sign and confirm, which is convenient for quality responsibility tracing, and provides reference basis for subsequent similar projects; (4) The method ensures quality, considers cost control and resource recovery, processes wall column steel positioning frames by using remaining steel heads on site, reduces material cost compared with purchasing finished positioning parts; 3% to 5% of grade I fly ash is mixed during concrete mixing, which reduces cement consumption and carbon emission, reduces the risk of dry shrinkage cracks by improving the workability of concrete, avoids waste of labor and materials caused by quality defects, shortens the construction period, meets the cost and progress control requirements of EPC engineering general contracting projects, especially adapts to the safety and durability requirements of public buildings, strengthens the management and control of key links, provides a safe and comfortable environment for people's activities in public buildings, and solves the problem that existing measures are not adapted to the special needs of public buildings. DETAILED DESCRIPTION

[0016] In order to make the purpose, process conditions and advantages of the present application clearer and more apparent, the present application is further described in detail in combination with the following implementation examples, but the implementation of the present application is not limited to this. According to ordinary technical knowledge and conventional means in the art, various substitutions and changes are made without departing from the above technical idea of the present application, which should be included in the scope of the present application. The specific implementation examples described herein are only used to explain the present application and are not used to limit the present application.

[0017] Example 1 The embodiment provides a method for preventing and treating construction quality defects, comprising the following steps: Step S1: classifying the quality defects occurring in the construction process into four types of concrete floor cracks, wall and column embedded steel displacement, roof leakage and wall cracks; Step S2: designing corresponding prevention measures for the four types of quality defects occurring in the construction process, wherein the prevention measures need to meet the requirements of the construction design drawings of the present project; Step S3: according to the design of each type of prevention measure, the prevention construction of each type of quality defect is carried out, and key process acceptance records need to be retained during the construction process, and the acceptance records need to be signed and confirmed by the technical person in charge of the construction unit and the supervision engineer.

[0018] Example 2 The embodiment is further limited on the basis of the above-mentioned embodiment, and the process of preventing and treating the concrete floor cracks occurring in the building construction process in step S3 is: Step S311: written technical disclosure is performed on the construction team, and the operation parameters, quality standards and acceptance requirements of each step are clear. The disclosure content includes template support calculation data, concrete mix ratio, curing method, load limit value; the disclosure record is signed and confirmed by the discloser and the disclosed person, and is stored for archiving; step S312: design the template support system according to the design thickness of the concrete floor and the construction live load; wherein the vertical rod adopts Φ48*3.5mm steel pipe, the vertical rod spacing is not greater than 1.5m, the horizontal rod step distance is not greater than 1.8m, the main keel adopts 100*100mm wood square, the secondary keel adopts 50*100mm wood square and the spacing is not greater than 300mm; the rigidity of the support system is ensured to be not less than 1.2 times of the total load of the upper part, and the strength is not less than 1.1 times of the total load of the upper part; when erecting, the bottom of the vertical rod is paved with 50mm thick wood footboard, 100mm thick gravel cushion is laid under the footboard, the vertical rod and the horizontal rod are rigidly connected by right angle fasteners, and an adjustable support is arranged at the top of each vertical rod, the length of the support screw rod extending out of the top of the steel pipe is not greater than 200mm; Step S313: control the water-cement ratio of the concrete not greater than 0.55, the sand ratio 35%~40%, and the slump 120mm±20mm according to the design concrete strength grade of the floor; the concrete is mixed by weight ratio, and the interval time from the completion of the concrete mixing to the completion of the pouring is not greater than 120min; before pouring, the floor steel mesh is checked, and the Φ12mm steel reinforcement stool is used to support the upper iron steel; the pouring is carried out in layers, and the thickness of each layer is not greater than 500mm, the high-frequency vibrating rod is used for vibrating, the vibrating point spacing is not greater than 400mm, and the concrete surface is not obvious bubble escaping and appears floating slurry; Step S314: start curing within 12h after the completion of the concrete pouring: when the environmental temperature is greater than 5℃, cover the geotextile and spray water for curing, the spraying frequency is every 2h~3h, the geotextile is kept wet, and the curing time is not less than 7 days; when the environmental temperature is not greater than 5℃, cover the fire-retardant insulation quilt combined with electric heat tracing for curing, the electric heat tracing temperature is controlled at 5~15℃, and the curing time is not less than 14 days; walking or piling up sundries on the floor is prohibited during the curing period; Step S315: any load is prohibited to be applied within 12h after the completion of the concrete pouring; after 12h, if building materials need to be piled up, a dispersed piling up method is adopted, the single piling up area is not less than 0.3m 2 , the piling up strength is not greater than 80% of the design live load of the floor, and the piling up height is not greater than 1.2m; the construction personnel avoid standing in the same position for a long time when operating, and heavy tools with a weight greater than 50kg are strictly prohibited to be dragged on the floor; Step S316: Before template removal, take the same condition curing concrete test block to carry out compression strength test, when the test block strength reaches 75% above the design concrete strength grade of floor, the template can be removed; the removal sequence is to remove secondary keel first, then main keel, then horizontal rod, and finally vertical rod, and strong pry is prohibited; the removed template and supporting parts are classified and stacked to the floor area which has reached the design strength, and the stacking load is not greater than 1.0 kN / m 2 ; after template removal, the floor surface is inspected, if the width of micro crack is not greater than 0.2 mm, epoxy resin slurry is used for injection sealing; if the crack width is greater than 0.2 mm, a special treatment scheme needs to be formulated, and after confirmation by the design unit, it is implemented.

[0019] In the step S312, after the template supporting system is erected, pre-pressing is carried out by using 2.0 kN / m 2 uniform load, the pre-pressing time is not less than 24 h, and after pre-pressing, the vertical rod settlement is not greater than 10 mm and has no obvious deformation, so that the next process can be entered.

[0020] In the step S313, when the concrete is mixed, 3% to 5% of grade I fly ash by mass of cement is mixed, the fly ash water demand ratio is not greater than 100%, and the loss on ignition is not greater than 5%, so as to reduce the dry shrinkage rate of concrete.

[0021] In the step S314, when the environmental temperature is greater than 30℃, shading net is additionally arranged above the geotextile to avoid direct sunlight to cause rapid evaporation of water on the concrete surface.

[0022] In the step S315, load warning signs are arranged on the floor to mark the allowed stacking area and stacking limit, and a full-time safety officer inspects once every 2 h, records the load stacking condition and keeps the inspection record.

[0023] In the step S316, after the template is removed, the floor surface is inspected, if the width of micro crack is not greater than 0.2 mm, epoxy resin slurry is used for injection sealing; if the crack width is greater than 0.2 mm, a special treatment scheme needs to be formulated, and after confirmation by the design unit and issuing of written opinions, it is implemented, and the treatment record is kept and filed.

[0024] Example 3: In this embodiment, the process of preventing and treating the displacement of the pre-embedded steel bars in the wall and column in the step S3 is further limited as follows: Step S321: Process the wall and column steel reinforcement positioning frame with the on-site remaining steel reinforcement head with a diameter not less than Φ16: the positioning frame of the frame column is made according to the column section size, the spacing of the main reinforcement slot in the positioning frame is consistent with the design spacing of the column main reinforcement, and each of the two is provided at a height of 1.0 m from the floor surface and the upper opening of the formwork; the positioning frame of the shear wall door and window opening hidden column is made according to the design size of the opening, the positioning frame is fixed with the hidden column main reinforcement, and is provided at a height of 20 cm to 30 cm from the top of the plate; the wall body distribution reinforcement positioning frame adopts an inner top and outer clamping structure, the spacing of the horizontal reinforcement slot of the frame body matches the design spacing of the wall body vertical reinforcement, and is installed at a height of 2 cm to 3 cm from the top of the wall and embedded in the wall formwork; a connecting section of 10 cm in length is processed at both ends of all the positioning frames, and adjacent positioning frames are connected by welding Φ8 steel bars; Step S322: The wall and column main reinforcement is bound and fixed with the upper and lower reinforcement of the bottom plate, each reinforcement binding point is not less than 3, and Φ12 additional reinforcement is additionally provided within a range of 500 mm from the root of the reinforcement, and the additional reinforcement is welded and fixed with the bottom plate reinforcement; before concrete pouring, the verticality of the wall and column reinforcement is reviewed by using a theodolite, if deviation is found, the deviation is slowly adjusted by using a 1:6 slope, and forced bending is prohibited; Step S323: During concrete pouring, a full-time reinforcement worker is arranged to stand by, a vibrating rod is used for vibration, and direct collision of the vibrating rod with the reinforcement is avoided; after every 300 mm of concrete is poured, the position of the reinforcement is reviewed once, if displacement occurs, pouring is immediately stopped, and the displaced reinforcement is treated by adding a reinforcement by welding: the diameter of the reinforcement is the same as that of the main reinforcement, the Ⅱ grade steel reinforcement is welded on both sides of the main reinforcement, and the Ⅰ grade steel reinforcement is welded on both sides of the main reinforcement, after the treatment is completed, the supervision unit checks and accepts it, and signs to confirm that it can continue pouring; Step S324: Within 24 hours after concrete pouring is completed, the position of the wall and column reinforcement is reviewed again, the displacement condition and treatment measures are recorded, a wall column reinforcement displacement monitoring record table is formed, and the table is kept and filed after being signed and confirmed by the technical person in charge of the construction unit and the supervision engineer.

[0025] Embodiment 4 In the above embodiment, the process of preventing and treating roof leakage in step S3 is further limited as follows: Step S331: Determine the position of the water outlet according to the design requirements, and use 1:8 volume ratio of cement and perlite to lay the slope layer, with a slope of not less than 2%; During the construction of the slope layer, set a control point every 2m to ensure that the flatness deviation of the slope layer surface is not more than 5mm / m; After the slope layer is maintained for 7 days, perform the water test, and observe whether the drainage is smooth and there is no water accumulation phenomenon before entering the next process. The water test image is recorded; Step S332: At the gutter, eaves gutter, eaves, deformation joint, water, pipeline port and water outlet, first lay a 3mm thick SBS modified asphalt waterproof roll as an additional layer, and the additional layer roll and the base layer are constructed by full adhesion method; The additional layer roll at the pipeline port should wrap the pipeline around the circle, and the roll closing end is fixed with a metal hoop, and the surface of the metal hoop is painted with anti-rust paint; Step S333: The waterproof layer uses 4mm thick SBS modified asphalt waterproof roll, and the laying direction is parallel to the slope of the roof, with a long side lap width of not less than 100mm and a short side lap width of not less than 150mm; When laying the roll, use a hot air welding machine to heat the lap joint to ensure that the lap joint is fused and bonded. After bonding, use a craft knife to check the lap joint, and no delamination is qualified; The end of the vertical surface roll is embedded into the pre-set groove of the vertical wall, the groove is filled with polyurethane sealant, and the fullness of the sealant is not less than 90%; Step S334: The pipeline port penetrating the waterproof layer is sealed twice with C30 fine stone expansion waterproof impermeable concrete: the first sealing is to 1 / 2 of the diameter of the pipeline, and the second sealing is to the roof slope layer elevation after 3 days of maintenance. Both times of sealing should be vibrated and compacted; After the construction of the waterproof layer is completed, perform the 24h water storage test, and after observing that there is no leakage, fill in the roof water storage test record, and keep it in the archives after being signed and confirmed by the construction unit, supervision unit and construction unit.

[0026] Example 4: On the basis of the above-mentioned embodiment, the process of preventing and treating the wall cracks in step S3 is further limited as follows: Step S341: The mortar is mixed by weight ratio according to the design mortar strength grade; 0.3% of the cement quality of the mortar thickening agent is mixed during mixing to improve the mortar workability, and the mortar is used within 3 hours after mixing is completed, and the mortar beyond the initial setting time is prohibited from use; Step S342: The filler wall is made of MU10 autoclaved aerated concrete block, and the block is wetted 1-2 days before being built; the water content of common bricks, hollow bricks and perforated bricks needs to reach 10%-15%, and the water content of lime sand bricks and fly ash bricks needs to reach 8%-12%, and there is no obvious water accumulation on the surface after watering; before building, the wall length and block size are drawn to draw the arrangement diagram, and the skin number rod is set, and the mortar joint thickness is marked on the skin number rod, wherein the horizontal mortar joint is 15mm±2mm, and the vertical mortar joint is 20mm±2mm; during building, the one-order and one-ding group building method is used, and the up-down skin block staggered joint length is not less than 1 / 3 of the block length; Step S343: The filler wall and the concrete column and wall connecting part are provided with Φ6@500 tie bars, the tie bars extend into the wall by not less than 1000mm, and the tail end is bent by 90°; the tie bars are fixed by the way of planting, the drilling diameter is Φ8mm, the hole depth is not less than 10 times of the tie bar diameter, the tie bar planting glue is the epoxy-based adhesive, the tie bar is maintained for 7 days after planting, the pull-out test is carried out, and the pull-out test record is kept after being signed by the supervising engineer; Step S344: The filler wall is plastered 7 days after building, and the plastering is divided into two layers: the bottom layer plastering thickness is 8-10mm, the surface layer plastering thickness is 5mm-7mm, and the interval time between the two layers of plastering is not less than 24h; before plastering, the 400mm wide alkali-resistant mesh cloth is pasted at the interface of different materials, and the mesh cloth overlap width is not less than 100mm; within 24h after plastering is completed, the earthwork cloth is covered and watered, the maintenance time is not less than 7 days, the watering frequency is not less than 3 times a day, and the plastering surface is prohibited from being collided during the maintenance period.

[0027] Example 5: Based on the above-mentioned examples, a specific engineering example is provided as follows: I. Project Overview Based on the science and technology innovation zone starting area primary and secondary school project EPC general contracting, the project contains three sub-projects: 24-class primary school, total building area 19500m 2 , ground 17000m 2 , underground 2500m 2 , 4-layer frame structure, building height 17.4m, 36-class primary school total building area 24600m 2 , ground 22000m 2 , underground 2600m 2 , 4-layer frame shear wall structure, building height 22.57m, 36-class junior high school (total building area 29300m 2 , ground 26500m 2 , underground 2800m 2, 4-storey frame structure, building height 19.8m.

[0028] Project key engineering quantity: total steel consumption 6170t, concrete 4.06 million m³, masonry 14980m³, construction period 715 days, quality target is engineering quality, four types of construction quality risk need to be controlled, the following will be implemented in combination with the specific sub-item construction link.

[0029] II. Concrete floor crack prevention and implementation, taking 24 class primary school teaching building 3 floor as an example 24 class primary school teaching building 3 floor design thickness 120mm, concrete strength grade C30, construction live load according to 2.0kN / m 2 , implementation process as follows: 1. Technical briefing 3 days before construction, project technician (with intermediate engineer title) to carpentry team, concrete team, steel reinforcement team for written briefing, briefing file clear: Formwork support checking data: vertical rod spacing 1.2m (less than 1.5m limit), horizontal rod step 1.5m (less than 1.8m limit), support system stiffness checking value 1.3 times upper total load, strength checking value 1.2 times upper total load; Concrete mix proportion: cement (P.O42.5): sand (medium sand): stone (5~25mm gravel): water: grade I fly ash = 1:1.8:2.5:0.52:0.15 (water-cement ratio 0.52≤0.55), sand ratio 38% (35%~40% interval), slump 120mm±10mm; Load limit value: prohibited loading within 12h after pouring, 12h after stacking ≤1.6kN / m 2 (80% of design live load 2.0kN / m 2 ), stacking height ≤1.2m.

[0030] Briefing record signed by technician (Jin), carpentry team leader (Cao), concrete team leader (Guan), kept in project technical file.

[0031] 2. Formwork support system design and preloading Support erection: vertical rod uses Φ48×3.5mm steel pipe (wall thickness actually measured 3.48mm, meets the requirements), vertical rod bottom lays 50mm thick ×200mm wide through length pine footboard, footboard below lays 100mm thick graded gravel cushion (compaction coefficient ≥0.93); main keel uses 100×100mm batten (moisture content 12%), secondary keel uses 50×100mm batten (spacing 250mm≤300mm), vertical rod and horizontal rod are rigidly connected with right angle fasteners, vertical rod top adjustable support screw rod extension length 150mm≤200mm; Pre-press verification: After the erection is completed, the woven bag filled with sand (bulk density 18 kN / m³) is used to simulate 2.0 kN / m 2 Pre-press, pre-press time 24h, set 6 settlement observation points (floor corners and middle), the maximum settlement after pre-press is 8mm≤10mm, no obvious deformation, after the supervision engineer (Zhang) acceptance qualified into the next process.

[0032] 3. Concrete mixing and pouring Mixing measurement: JS500 forced mixer is used for mixing, cement measurement deviation +1.2% (≤±2%), sand measurement deviation +2.5% (≤±3%), stone measurement deviation 2.1% (≤±3%), fly ash (water demand ratio 98%, loss on ignition 4.2%) dosage 4% (3%~5% interval), interval time from mixing completion to pouring completion is 90min≤120min (normal temperature 25℃); Pouring control: Before pouring, check the floor steel mesh (Φ8@150 double-layer double-direction), use Φ12mm steel stool (spacing 1.2m≤1.5m) to support the upper iron steel, the measured thickness of the protective layer is 15mm (design 15mm, deviation 0mm); Pouring layer thickness is 400mm≤500mm, use ZN-50 high-frequency vibrating rod (vibration frequency 12000r / min) to vibrate, vibrating point spacing 350mm≤400mm, until the concrete surface is free of bubbles and presents uniform floating slurry.

[0033] 4. Concrete curing and load control Curing measures: Start curing 8h after pouring (normal temperature 25℃), cover 200g / m 2 Watering with geotextile, watering frequency every 2.5h (keep geotextile wet), curing time 9 days≥7 days; On the 5th day, add shading net with shading rate 75% above the geotextile to avoid too fast evaporation of surface water; Load control: Prohibit personnel walking within 12h after pouring, after 12h, when stacking cement (single package 50kg), the single stacking area is 0.4m 2 ≥0.3m 2 , stacking height 1.0m≤1.2m, stacking strength 1.2kN / m 2 ≤1.6kN / m 2 ; Set load warning signs (mark the allowed stacking area≤1.6kN / m 2 ) at the corners of the floor, the full-time safety officer (Huang) patrols every 2h, records the stacking position and load value, and the patrol records are kept for archiving.

[0034] 5. Template removal and crack treatment form removal verification: 7 days after pouring, take the same condition curing test block (number SY-20220510), the compressive strength test value is 24.8 MPa ≥ 22.5 MPa (75% of C30), and the form is removed after the supervision confirmation; The removal sequence is: secondary keel → main keel → horizontal bar → vertical bar, and strong pry is prohibited; The removed templates are classified and stacked on the 2nd floor slab that has been poured for 28 days (stacking load 0.8 kN / m2≤1.0 kN / m2). Crack inspection: After the form is removed, the floor surface is inspected, 2 micro-cracks with a width of 0.15 mm are found, and epoxy resin paste (model E-44) with a solid content of 92% is used for injection and sealing; There is no crack with a width of >0.2 mm, and no special treatment is required.

[0035] III. Displacement prevention and implementation of pre-embedded steel bars in walls and columns (taking the frame column and shear wall of the 36th Primary School Comprehensive Building as an example) The 36th Primary School Comprehensive Building is a frame shear wall structure, the frame column section size is 600x600mm (main reinforcement Φ25@200), the shear wall thickness is 200mm (vertical reinforcement Φ12@150), and the implementation process is as follows: 1. Steel reinforcement positioning frame processing and installation Positioning frame processing: using the remaining Φ18 steel rod head (diameter ≥ 16mm) to process the positioning frame: the positioning frame of the frame column is made according to the 600x600mm section, the main reinforcement slot spacing is 200mm (consistent with the design, error 1mm≤2mm); The positioning frame of the concealed column of the door and window opening of the shear wall (opening width 1500mm) is made according to the size of 1500mm, and the slot spacing is 150mm; The positioning frame of the wall distribution steel bar is made of inside top and outside clamping type (inside top vertical reinforcement, outside clamping formwork), and the horizontal reinforcement slot spacing is 150mm; All positioning frames are processed with 10cm connecting sections (length unit cm) at both ends; Positioning frame installation: one positioning frame is arranged at 1.0m high from the slab surface and the top of the form for the frame column, and is fixed with the main reinforcement (binding point spacing 120mm≤150mm); The positioning frame of the concealed column of the shear wall is arranged at 25cm (20cm~30cm interval) from the top of the slab; The positioning frame of the wall is installed at 2.5cm from the top of the wall and is embedded in the 18mm thick bamboo plywood form; Adjacent positioning frames are connected by Φ8 steel bars (welding length 32mm≥4d, d=8mm) to form an integrated positioning system.

[0036] 2. Pre-embedded steel bar fixing and review Reinforcement fixing: the frame column main reinforcement reinforcement (Φ25) is fixed with the upper and lower reinforcement (Φ20@150) of the bottom plate, and each reinforcement is fixed with 4 points (≥3 points), which is bound with double Φ0.9mm fireproof wire; Within 500mm of the reinforcement root, Φ12 additional reinforcement is added, and the additional reinforcement is double-face welded with the bottom plate reinforcement (welding length 60mm≥5d, d=12mm); Verticality verification: Before pouring, the verticality of the reinforcing bars is verified using a DJ2 theodolite. The verticality deviation of the frame columns is 2mm / m≤3mm / m, and the verticality deviation of the shear wall is 1.5mm / m, with no deviations exceeding the standard. If a vertical bar of the shear wall is found to have a deviation of 5mm / m, it is slowly adjusted with a slope of 1:6 (adjustment length 30cm). Forced bending is prohibited.

[0037] 3. Pouring monitoring and displacement handling On-site monitoring: During concrete pouring, a dedicated steelworker (Li) was assigned to supervise the process. A ZN-35 vibrator (vibration radius 280mm≤300mm) was used to vibrate the concrete to avoid direct contact between the vibrator and the steel bars. The position of the steel bars was checked with a steel tape measure every 300mm of concrete poured (corresponding to a pouring time of 20 minutes). Displacement handling: When the pouring height reached 1.2m, it was found that the main reinforcement of one frame column was displaced by 8mm. The pouring was stopped immediately, and Φ25 pad reinforcement (same diameter as the main reinforcement) was welded on both sides (Grade II steel, welding length 125mm ≥ 5d, d=25mm). After the treatment was completed and the supervisor accepted it, the pouring continued.

[0038] 4. Post-pouring verification and recording Twenty hours after the pouring was completed, the position of the wall and column reinforcement was checked again: the maximum displacement of the main reinforcement of the frame column was 6mm, and the maximum displacement of the vertical reinforcement of the shear wall was 5mm, both of which met the requirements; the displacement and handling measures were recorded, and a "Wall and Column Reinforcement Displacement Monitoring Record Form" (No. WZ-20220608) was formed. The record was signed and confirmed by the project technical person in charge (Zhao) and the supervising engineer (Zhang) and then kept in the technical archives.

[0039] IV. Roof Leakage Prevention Implementation (Taking the Roof of a 36-Class Junior High School Teaching Building as an Example) The roof of the junior high school teaching building with 36 classes is an accessible roof. The minimum thickness of the slope-forming layer is 30mm. The waterproof layer consists of a 3mm SBS modified bitumen membrane additional layer + a 4mm SBS modified bitumen membrane waterproof layer. The implementation process is as follows: 1. Construction and verification of roof slope-finding layer Slope-finding layer laying: A 1:8 volume ratio of cement perlite (P.O32.5 cement: perlite = 1:8) is used to lay the slope-finding layer with a slope of 2% (the slope is increased to 5% within 500mm around the drain outlet); during construction, an elevation control point is set every 2m (pre-embedded with Φ10 steel bar heads to mark the elevation), and the surface flatness deviation of the slope-finding layer is 4mm / m≤5mm / m; Water splash test: After the slope layer has been cured for 7 days, a Φ50 water pipe (outlet pressure 0.2MPa) was used to simulate moderate rainfall and observe the drainage path: rainwater flowed to the drain outlet through a 2% slope and there was no water accumulation; the water splash test was recorded by video (including time watermark) and archived.

[0040] 2. Construction of additional waterproof layer and waterproof layer Additional layer construction: At gutters, eaves, expansion joints, Φ110 PVC drainage pipe openings and downspouts, first lay a 3mm thick SBS modified bitumen waterproof membrane (width ≥500mm) as an additional layer. The additional layer is fully bonded to the base layer (bonding area ≥90%). At the drainage pipe openings, the additional membrane wraps around the pipe (height ≥300mm), and the membrane ends are fixed with Φ1.2mm stainless steel clamps (fixing spacing ≤120mm). The surface of the metal clamps is coated with 80μm thick anti-rust paint (red lead anti-rust paint). Waterproofing layer construction: The waterproofing layer uses 4mm thick SBS modified bitumen waterproof membrane (model PY-Ⅰ), laid parallel to the roof slope (from high to low), with a long side overlap width of 120mm ≥ 100mm and a short side overlap width of 160mm ≥ 150mm; a hot air welding machine (model RH-600) is used to heat the overlap joints at a temperature of 190℃ (180-200℃ range) to ensure the overlap joints are melted and bonded; after bonding, the overlap joints are randomly checked with a utility knife (sampling ratio 12% ≥ 10%), and no delamination is observed; the membrane termination on the vertical surface is embedded in a pre-set groove on the vertical wall (depth 12mm ≥ 10mm, width 25mm ≥ 20mm), and the groove is filled with 96% solids content polyurethane sealant (model PU-100), with a sealant fullness of 92% ≥ 90%.

[0041] 3. Pipeline sealing and water storage test Pipe opening sealing: The Φ110 PVC drainage pipe opening is sealed in two stages using C30 fine stone expansion waterproof and seepage-resistant concrete (seepage resistance grade P6): The first sealing is carried out to 1 / 2 of the pipe diameter (55mm in height), with a vibration frequency of 6500r / min (≥6000r / min). After curing for 3 days, the second sealing is carried out (to the slope layer elevation), and the concrete is vibrated to ensure compaction. Water storage test: 48 hours after the waterproof layer is completed, a 24-hour water storage test is conducted. The water level is ≥50mm. Twelve observation points are set up along the perimeter of the roof and pipe openings. There is no leakage within 24 hours. The "Roof Water Storage Test Record" (No. FS-20220820) is filled out and jointly signed and confirmed by the construction unit (Langfang Airport Group, Mr. Wang), the supervision unit (Boke Engineering Management, Mr. Zhang), and the construction unit (China Railway Construction Bridge Bureau, Mr. Jin), and is kept on file.

[0042] V. Implementation of Wall Crack Prevention (Taking the Plastering of the Infill Wall of a 24-Class Primary School Dormitory Building as an Example) The infill walls of the No. 24 primary school dormitory building are constructed using MU10 autoclaved aerated concrete blocks (600×200×240mm), and plastering is done with M5 mixed mortar. The implementation process is as follows: 1. Mortar mixing and block preparation Mortar mixing: according to the design M5 mortar mixing ratio (cement P.O32.5: medium sand: water: mortar thickening agent = 1:3:0.8:0.003), the cement measurement deviation is +1.5%≤±2%, the sand measurement deviation is -2.3%≤±3%, and the water measurement deviation is +0.8%≤±1%; 0.3% of the cement quality is mixed with mortar thickening agent (solid content 83%≥80%), and the mortar is used within 2.5h after mixing (≤3h), without super initial setting time; Block wetting: the blocks (ordinary aerated concrete blocks) are wetted by watering one day before masonry, and the water content is detected by a water content tester, which is 12% (10%-15% interval), and there is no obvious water accumulation on the surface after watering; the water content of the grey sand brick is 9% (8%-12% interval), and it is separately stacked and controlled.

[0043] 2. Filled wall masonry and tie bar construction masonry control: before masonry, draw the masonry arrangement diagram according to the wall length (6.3m) and block size, and set the skin number bar (mark the horizontal mortar joint 15mm±1mm, vertical mortar joint 19mm±1mm); use one order one Ding masonry method, and the upper and lower skin blocks are staggered with a lap joint length of 220mm≥1 / 3 block length (200mm); Tie bar construction: Φ6@500 tie bars are arranged at the connection part of the filled wall and the concrete column, with a length of 1200mm≥1000mm extending into the wall, and a 90° hook at the end; the tie bars are fixed by the way of anchoring, with a drilling diameter of Φ8mm and a hole depth of 60mm≥10d (d=6mm, 10d=60mm), and the anchoring glue is epoxy-based adhesive (compressive strength 65MPa≥60MPa); after anchoring, maintain for 7 days, and randomly select 3 for pull-out test, with a tensile bearing capacity of 6.2kN, 6.5kN and 6.3kN respectively, all≥5.8kN per root, and the pull-out test record (number LJ-20220715) is signed by the supervising engineer and kept.

[0044] 3. Wall plastering and curing Plastering construction: plastering is carried out 7 days after the completion of filled wall masonry, with two layers of construction: bottom layer plastering thickness 9mm (1:3 cement mortar), surface layer plastering thickness 6mm (1:2.5 cement mortar), and the interval time between the two layers of plastering is 26h≥24h; before plastering, 400mm wide alkali-resistant mesh cloth (unit area mass 165g / m2≥160g / m2) is pasted at the interface of block concrete column, with a lap width of 120mm≥100mm; Curing measures: cover the earthwork cloth and sprinkle water for curing 12h after plastering is completed, with a curing time of 8 days≥7 days, and sprinkle water 3 times a day (8am, 2pm, 6pm), to keep the surface of the plastered layer wet; during the curing period, the wall surface is prohibited from being collided (prohibition collision warning signs are set), and no hollowing, cracking occurs.

[0045] Six, effect verification After the construction of the above prevention method, the project quality acceptance results are as follows: The occurrence rate of concrete floor cracks: The occurrence rates of floor cracks of 24-class primary school, 36-class primary school and 36-class junior high school are 0.3%, 0.2% and 0.4% respectively, which are far lower than the industry average level of 1.5%; Steel displacement deviation: The maximum deviation of frame column reinforcement displacement is 8mm, and the maximum deviation of shear wall vertical reinforcement displacement is 6mm, both of which meet the requirement of displacement ≤10mm in the Concrete Structure Engineering Construction Quality Acceptance Specification (GB50204-2015); Roof leakage rate: The roof water storage test of the three sub-items has no leakage, and there is no leakage complaint after one year of rain season visit; Wall crack rate: The crack occurrence rate of the filled wall after plastering is 0.2%, which is lower than the industry average level of 0.8%; Cost and efficiency: The use of remaining steel to process and position the frame saves material cost of 32,000 yuan, the addition of fly ash in concrete saves cementitious material cost of 85,000 yuan, there is no quality rework, the construction period is shortened by 12 days, and the EPC project quality, cost and progress collaborative control target is met.

[0046] The above is only the preferred embodiment of the present application, and does not limit the present application in any form. Any simple modification or equivalent change made according to the technical essence of the present application to the above embodiment falls within the protection scope of the present application.

Claims

1. A method for preventing and controlling common quality defects in building construction, characterized in that, Includes the following steps: Step S1: Classify common quality defects that occur during the construction process into four categories: concrete floor slab cracks, displacement of embedded steel bars in walls and columns, roof leakage, and wall cracks. Step S2: Design corresponding prevention and control measures for the four types of common quality defects that occur during the construction process, and the prevention and control measures must meet the requirements of the construction design drawings of this project; Step S3: Based on the design of each type of prevention and control measure, carry out the prevention and control construction for each type of common quality defects. During the construction process, key process acceptance records must be kept, and the acceptance records must be signed and confirmed by the technical person in charge of the construction unit and the supervising engineer.

2. The method for preventing and controlling common construction quality defects according to claim 1, characterized in that, In step S3, the process of preventing and controlling cracks in concrete floor slabs that occur during building construction is as follows: Step S311: Provide written technical instructions to the construction team, clarifying the operational parameters, quality standards, and acceptance requirements for each step. The instructions should include formwork support calculation data, concrete mix proportions, curing methods, and load limits. The instructions record should be signed and confirmed by both the instructor and the recipient, and then archived. S312: Design a formwork support system based on the design thickness of the concrete floor slab and the construction live load; wherein, the uprights are made of Φ48×3.5mm steel pipes, the spacing between uprights is no more than 1.5m, the step distance of the horizontal bars is no more than 1.8m, the main joists are made of 100×100mm timber, and the secondary joists are made of 50×100mm timber with a spacing of no more than 300mm; ensure that the rigidity of the support system is no less than 1.2 times the total load above, and the strength is no less than 1.1 times the total load above; during erection, a 50mm thick continuous wooden scaffold board is laid at the bottom of the uprights, and a 100mm thick crushed stone cushion layer is laid under the scaffold board; the uprights and horizontal bars are rigidly connected by right-angle couplers; each upright is equipped with an adjustable support at the top, and the length of the support screw extending out of the top of the steel pipe is no more than 200mm; Step S313: Control the water-cement ratio of the concrete to be no greater than 0.55, the sand ratio to be 35%~40%, and the slump to be 120mm±20mm according to the design concrete strength grade of the floor slab; use weight ratio for concrete mixing, and the interval between the completion of concrete mixing and the completion of pouring should not exceed 120 minutes; before pouring, check the steel mesh of the floor slab and use Φ12mm steel bar supports to support the upper steel bars; pour in layers, with each layer not exceeding 500mm in thickness, and use a high-frequency vibrator to vibrate, with the vibration point spacing not exceeding 400mm, until no obvious air bubbles escape from the concrete surface and a layer of laitance appears; Step S314: Curing shall commence within 12 hours of concrete pouring: When the ambient temperature is above 5℃, cover with geotextile and water for curing, watering every 2-3 hours to keep the geotextile moist, and the curing period shall not be less than 7 days; when the ambient temperature is below 5℃, cover with flame-retardant insulation blanket and combine with electric heat tracing for curing, with the electric heat tracing temperature controlled at 5-15℃, and the curing period shall not be less than 14 days; during the curing period, walking on the floor slab or piling up debris is prohibited. Step S315: No load shall be applied within 12 hours after concrete pouring; if building materials need to be stacked after 12 hours, they shall be stacked in a dispersed manner, with each stacking area not less than 0.3m². 2 The surcharge intensity shall not exceed 80% of the design live load of the floor slab, and the surcharge height shall not exceed 1.2m. Construction personnel shall avoid standing in the same position for a long time during operation, and it is strictly forbidden to drag heavy tools weighing more than 50kg on the floor slab. Step S316: Before removing the formwork, take concrete test blocks cured under the same conditions for compressive strength testing. Removal is only permitted when the test block strength reaches 75% or more of the design concrete strength grade of the floor slab. The removal sequence is: first remove the secondary joists, then the main joists, then the horizontal bars, and finally the vertical bars. Forced prying or prying is prohibited. The removed formwork and supporting components should be sorted and stacked in the floor slab area that has reached the design strength, with a stacking load not exceeding 1.0 kN / m². 2 After the formwork is removed, the surface of the floor slab should be inspected. If microcracks with a width of no more than 0.2 mm are found, they should be sealed with epoxy resin grout. If the crack width is greater than 0.2 mm, a special treatment plan should be developed and implemented after confirmation by the design unit.

3. The method for preventing and controlling common construction quality defects according to claim 2, characterized in that, In step S312, after the template support system is erected, a force of 2.0 kN / m is applied. 2 The uniformly distributed load is preloaded for no less than 24 hours. After preloading, the settlement of the uprights should not exceed 10mm and there should be no obvious deformation before proceeding to the next process.

4. A method for preventing and controlling common construction quality defects according to claim 2 or 3, characterized in that, In step S313, 3% to 5% of Grade I fly ash by mass of cement is added during concrete mixing. The water requirement of the fly ash is not greater than 100%, and the loss on ignition is not greater than 5%, in order to reduce the drying shrinkage rate of the concrete.

5. A method for preventing and controlling common construction quality defects according to claim 2 or 3, characterized in that, In step S314, when the ambient temperature is greater than 30℃, a shade net is added above the geotextile to prevent direct sunlight from causing the moisture on the concrete surface to evaporate too quickly.

6. A method for preventing and controlling common construction quality defects according to claim 2 or 3, characterized in that, In step S315, load warning signs are set on the floor slab to indicate the permitted stacking area and the stacking limit. A dedicated safety officer will patrol every 2 hours to record the load stacking situation and keep the patrol record.

7. A method for preventing and controlling common construction quality defects according to claim 2 or 3, characterized in that, In step S316, after the formwork is removed, the surface of the floor slab is inspected. If microcracks with a width of no more than 0.2 mm are found, they are sealed by injecting epoxy resin grout. If the crack width is greater than 0.2 mm, a special treatment plan needs to be formulated, and it is implemented after the design unit confirms it and issues a written opinion. The treatment record is kept and archived.

8. A method for preventing and controlling common construction quality defects according to any one of claims 1 to 3, characterized in that, In step S3, the process of preventing displacement of the pre-embedded steel bars in the central wall and column is as follows: Step S321: Use leftover steel bars with a diameter of not less than Φ16 to fabricate wall and column reinforcement positioning frames: the frame column positioning frames are made according to the column cross-section dimensions, the spacing of the main reinforcement slots in the positioning frames is consistent with the design spacing of the column main reinforcement, and one frame is set at a height of 1.0m from the floor slab and at the top of the formwork; the shear wall door and window opening concealed column positioning frames are made according to the opening design dimensions, the positioning frames are tied and fixed to the main reinforcement of the concealed column, and are set at a height of 20cm~30cm from the top of the slab; the wall distributed reinforcement positioning frames adopt an inner top and outer clamp structure, the spacing of the horizontal reinforcement slots in the frame matches the design spacing of the vertical reinforcement of the wall, are installed at a height of 2cm~3cm from the top of the wall, and are embedded in the wall formwork; all positioning frames have a 10cm connecting section fabricated at both ends, and adjacent positioning frames are welded together with Φ8 steel bars; Step S322: Tie the main reinforcement bars of the wall and column to the top and bottom reinforcement bars of the base slab. Each reinforcement bar should be tied at no less than 3 points. An additional Φ12 reinforcement bar should be added within 500mm of the root of the reinforcement bar. The additional reinforcement bar should be welded to the base slab reinforcement bar. Before pouring concrete, use a theodolite to check the verticality of the wall and column reinforcement bars. If a deviation is found, adjust slowly with a 1:6 slope. Forced bending is prohibited. Step S323: During concrete pouring, a dedicated steelworker shall be assigned to supervise the process throughout, using a vibrator to compact the concrete, avoiding direct contact between the vibrator and the steel reinforcement. After pouring 300mm of concrete, the position of the steel reinforcement shall be checked. If displacement is found, pouring shall be stopped immediately, and the displaced steel reinforcement shall be treated by adding and welding spacers: the diameter of the spacers shall be the same as that of the main reinforcement. Grade II steel spacers shall be welded to the main reinforcement on both sides, and Grade I steel spacers shall be welded to the main reinforcement on both sides. After the treatment is completed, the pouring can only continue after the supervision unit has inspected and approved it and signed its confirmation. Step S324: Within 24 hours after the concrete pouring is completed, the position of the wall and column reinforcement is checked again, the displacement and handling measures are recorded, and a wall and column reinforcement displacement monitoring record form is formed. The form is signed and confirmed by the technical person in charge of the construction unit and the supervising engineer and then kept in the archive.

9. A method for preventing and controlling common defects in building construction quality according to any one of claims 1 to 3, characterized in that, In step S3, the process of carrying out roof leakage prevention and control construction is as follows: Step S331: Determine the location of the roof drain according to the design requirements. The slope-forming layer is laid with cement perlite at a volume ratio of 1:8, with a slope of not less than 2%. During the construction of the slope-forming layer, set an elevation control point every 2m to ensure that the surface flatness deviation of the slope-forming layer is not greater than 5mm / m. After the slope-forming layer has been cured for 7 days, conduct a water-splashing test to observe whether the drainage is smooth. Only if there is no water accumulation can the next process be carried out. The water-splashing test is recorded on video. Step S332: At the gutters, eaves, eaves, expansion joints, flashing, pipe openings penetrating the waterproof layer, and drain outlets, first lay a 3mm thick SBS modified bitumen waterproof membrane as an additional layer. The additional layer membrane is fully bonded to the base layer. At the pipe openings, the additional layer membrane should wrap around the pipe. The membrane ends are fixed with metal hoops, and the surface of the metal hoops is coated with anti-rust paint. Step S333: The waterproof layer is made of 4mm thick SBS modified bitumen waterproof membrane. For the waterproof membrane, the laying direction should be parallel to the roof slope, with a long side overlap width of not less than 100mm and a short side overlap width of not less than 150mm. When laying the membrane, a hot air welding machine should be used to heat the overlap joints to ensure that the overlap joints are melted and bonded. After bonding, the overlap joints should be checked with a utility knife. If there is no delamination, it is considered qualified. The membrane termination on the vertical surface should be embedded in the pre-set groove on the vertical wall, and the groove should be filled with polyurethane sealant with a sealant fullness of not less than 90%. Step S334: The pipe opening penetrating the waterproof layer should be sealed twice with C30 fine stone expansion waterproof and seepage-resistant concrete: the first sealing should be to 1 / 2 of the pipe diameter, and after curing for 3 days, the second sealing should be carried out to the elevation of the roof slope layer. Both sealings should be vibrated to ensure compaction. After the waterproof layer construction is completed, a 24-hour water retention test should be carried out. After observing that there is no leakage, the roof water retention test record should be filled out and signed by the construction unit, supervision unit, and construction unit and then filed.

10. A method for preventing and controlling common defects in building construction quality according to any one of claims 1 to 3, characterized in that, In step S3, the process of carrying out construction to prevent and control wall cracks is as follows: Step S341: Mix mortar according to the designed strength grade using weight ratio; add 0.3% mortar thickener by mass of cement during mixing to improve workability; use the mortar within 3 hours of mixing; mortar exceeding its initial setting time is prohibited from use; Step S342: Use MU10 autoclaved aerated concrete blocks for the infill wall; moisten with water 1-2 days before construction: the moisture content of ordinary bricks, hollow bricks, and perforated bricks should reach 10%-15%, and the moisture content of lime-sand bricks and fly ash bricks should reach 8%-12%, with no obvious water accumulation on the surface after watering; before construction, draw a masonry arrangement diagram according to the wall length and block size, set a course gauge rod, and mark the mortar joint thickness on the course gauge rod, where the horizontal mortar joint is 15mm±2mm and the vertical mortar joint is 20mm±2mm; use a one-header-one-stretcher masonry method, with the overlap length of the upper and lower courses of blocks not less than 1 / 3 of the block length; Step S343: Infill wall and concrete Φ6@500 tie bars are installed at the connection points of concrete columns and walls. The tie bars extend into the wall for a length of not less than 1000mm and have a 90° hook at the end. The tie bars are fixed by anchoring. The hole diameter is Φ8mm and the hole depth is not less than 10 times the diameter of the tie bar. Epoxy adhesive is used for anchoring. After anchoring, the bars are cured for 7 days and a pull-out test is conducted. The pull-out test record is signed and confirmed by the supervising engineer and kept on file. Step S344: Plastering is carried out 7 days after the infill wall is completed. The plastering is done in two layers: the base plaster is 8~10mm thick and the top plaster is 5mm~7mm thick. The interval between the two plastering layers is not less than 24 hours. Before plastering, a 400mm wide alkali-resistant mesh is pasted at the interface between different materials. The overlap width of the mesh is not less than 100mm. After plastering is completed, the geotextile is covered and watered for curing within 24 hours. The curing time is not less than 7 days, and the number of waterings per day is not less than 3. During the curing period, the plaster surface is prohibited from being bumped.