Prefabricated House Finished Construction
Prefabricated house finished construction covers three core aspects: overall construction planning, construction preparation phase, and main construction processes.
Overall Construction Planning: This involves defining quality, safety, progress, cost objectives, and organizational structure. In terms of quality, the pass rate of sub-projects should reach 100%, the excellent rate of key processes should be ≥95%, the strength of foundation concrete should be ≥C30, the verticality deviation of prefabricated component installation should be ≤3mm/m, and the surface flatness should be ≤5mm/2m. The safety objective is 'zero deaths, zero serious injuries', with a minor injury frequency of ≤3‰, and both the certification rate of special operation personnel and the compliance rate of temporary electricity usage should be 100%. The total construction period should be controlled within 120 days, including 45 days for prefabricated component production, 50 days for on-site installation, and 25 days for decoration and finishing. The critical path is foundation construction → main structure installation → roofing works → completion acceptance. The cost objective is a unit construction cost of ≤1800 yuan/㎡, a material loss rate of ≤3%, and a machinery utilization rate of ≥85%. The organizational structure establishes a project management department with five specialized teams: technical, production, quality and safety, materials, and logistics.
Construction Preparation Phase: This includes drawing review, site leveling, and production control. Drawing review requires examining the prefabricated component splitting plan (wall panel dimensions ≤3.5m×6m, weight ≤8t), node connection details (such as sleeve grouting and grout-anchor lap joint details), and the positions of reserved holes (coordinate deviation of pre-embedded water and electricity pipelines ≤5mm), and utilizing BIM technology to optimize component clashes, lifting paths, and progress simulations. Site leveling requires a foundation bearing capacity of ≥150kPa, a drainage slope of ≥2%, the installation of a circular drainage ditch and a sump pit, a temporary road width of ≥4m (hardened with C20 concrete, thickness 150mm), and the division of areas for component stacking, material storage, and lifting operations. In production control, steel bar processing uses CNC stirrup benders (dimensional deviation ≤±5mm), mold acceptance requires steel mold joint gaps of ≤0.5mm and flatness of ≤2mm/m, concrete pouring uses pumping technology (vibration time of 30-45s per point), and factory inspection includes appearance (honeycomb area ≤0.02% of the component surface area, no through cracks), dimensions (length/width ±5mm, thickness ±3mm, diagonal difference ≤10mm), and strength (compressive strength of test blocks cured under the same conditions ≥100% of the design value).
Main Construction Processes: Taking foundation excavation and lifting preparation as examples. Foundation excavation uses a backhoe excavator, with a 300mm manual clearing reserved at the base, a slope ratio of 1:0.5, a 300mm wide drainage ditch and a 600mm×600mm×800mm sump pit at the bottom of the pit, foundation treatment involves laying 300mm thick graded sand and gravel (compaction coefficient ≥0.94), steel bar binding requires a protective layer thickness of 50mm for the foundation slab and a spacing deviation of ±10mm, formwork installation uses 18mm thick multi-layer boards (post spacing ≤1.2m), and concrete pouring uses C30 ready-mixed concrete (layer thickness ≤500mm, secondary troweling before initial setting, curing with film + flame-retardant cotton quilt for ≥14 days). Lifting preparation requires surveying and setting out to mark the wall panel positioning lines and 200mm control lines, and bedding construction involves laying 30mm thick bedding mortar.
