Construction Plan for Prefabricated Roof of Houses

The construction plan for the prefabricated roof of houses should cover key aspects such as project overview, construction preparation, and construction techniques, as detailed below:

I. Project Overview
Clarify basic project information, including building area, roof structure type, and design parameters. For example, a multi-story residential project with a total building area of 8,600 square meters adopts a prefabricated concrete composite floor system, with a design service life of 50 years and a seismic fortification intensity of 7 degrees. The prefabricated floor slabs include standard slabs (3000×1200×120mm) and irregular slabs, with a maximum single slab weight of 2.4 tons. The prefabricated layer has a concrete strength grade of C30, while the composite layer uses C35P6 waterproof concrete. The slab joint width ranges from 20 to 40mm, and the slab end resting length is ≥100mm.

II. Construction Preparation

1. Construction Organization: Establish a project department, clarify job responsibilities; form a professional construction team (including steel fixers, formwork workers, etc.); equip with a concrete mixing plant, pump trucks, and 25-ton truck cranes.
2. Material Preparation:
   • Prefabricated Components: Purchase roof slabs and ridge slabs that meet standards, check factory certificates and 28-day concrete strength reports (≥30MPa), and stack them using square timber supports with a stacking height of ≤6 layers.
   • Steel Bars: Select HRB400E grade φ10mm ribbed steel bars (for slab end anchoring) and φ6mm@300mm stirrups (for slab joint reinforcement).
   • Waterproof Materials: Use SBS waterproof membranes (tensile strength ≥800N/50mm), polyurethane waterproof coatings, and polysulfide building sealants.
3. Technical Preparation: Familiarize with design drawings, complete detailed layout design for prefabricated slabs, marking slab numbers, lifting directions, and reserved hole locations; prepare three-level technical disclosure documents, clarifying lifting techniques, composite layer construction, and waterproof joint treatment points; use a total station to verify axis deviations (±3mm) and set out elevation control lines.
4. Equipment Preparation: Inspect the truck crane's braking system, the welding strength of special lifting fixtures (tensile capacity ≥50kN), the verticality of disk-buckle scaffold uprights (≤1/2000), and the horizontal accuracy of laser line projectors (±1mm/10m).

III. Construction Techniques

1. Installation of Prefabricated Components: Set out positions on-site, lift components to designated locations using a crane, correct verticality and levelness, and secure them through welding or bolt connections.
2. Steel Bar Binding: Bind steel bars according to design requirements, ensuring spacing, diameter, and anchorage length meet standards, and welding quality is up to par.
3. Concrete Construction: Continuously pour C35P6 waterproof concrete for the composite layer, control slab joint width within 20-40mm, and cure according to specifications after pouring to prevent cracking.
4. Waterproof Layer Construction: Lay a 3+3mm double-layer SBS modified asphalt waterproof membrane on the roof, and treat joint areas (such as chimneys and exhaust pipes) with polysulfide building sealant to ensure tightness.