Specification Requirements for Prefabricated House Floor Slabs

The specification requirements for prefabricated house floor slabs cover multiple aspects such as production and acceptance, thickness control, and design of specific types of floor slabs, as detailed below:

I. Production and Acceptance Specifications for Prefabricated Components According to the Shandong Provincial Engineering Construction Standard 'Specifications for Production and Acceptance of Prefabricated Components in Assembled Monolithic Concrete Structure Engineering' (DB37/T 5020-2014), the production of prefabricated floor slabs must adhere to the principle of full-process quality control. The standard explicitly requires:

1. Material Management: Raw materials (such as cement, steel bars, and aggregates) must comply with national standards and be accompanied by quality certification documents; they must be inspected in batches upon arrival and can only be used after passing inspection.
2. Production Process: The dimensional deviation of molds must be controlled within ±2mm; the installation of steel bar frameworks must ensure accurate positioning and firm fixation; during concrete pouring, compaction must be thorough to avoid defects such as honeycombing and pitting.
3. Acceptance Criteria: Finished products must be inspected for appearance quality (such as cracks and damage), dimensional deviations (such as length ±5mm and width ±3mm), and positional deviations of embedded parts (such as a deviation of ≤5mm in the centerline of anchor bars); after passing acceptance, product identification (such as production date and component number) must be marked and stored by category.

II. Thickness Control Specifications for Floor Slabs Based on the 'Code for Design of Concrete Structures' (GB 50010-2010) and the 'Technical Specification for Concrete Structures of High-rise Buildings' (JGJ 3-2010):

1. Span-to-Thickness Ratio Limits: The span-to-thickness ratio (the ratio of calculated span to slab thickness) for one-way slabs must not exceed 30, and for two-way slabs, it must not exceed 40, to control deflection deformation.
2. Minimum Thickness Requirements: The minimum thickness of ordinary floor slabs is typically 60mm; for high-rise buildings, the thickness of floor slabs on general floors should not be less than 80mm; if embedded concealed pipes (such as electrical conduits) are present within the slab, the thickness must be increased to not less than 100mm to prevent pipe exposure or slab cracking.

III. Specifications for Prefabricated Ribbed Base Plate Concrete Composite Floor Slabs According to the 'Technical Specification for Prefabricated Ribbed Base Plate Concrete Composite Floor Slabs':

1. Scope of Application: Applicable to floor slabs in industrial and civil buildings with environmental categories of Class I (dry environment) or Class IIa (humid environment) and seismic fortification intensity ≤ 9 degrees.
2. Design Requirements: It is necessary to perform calculations for ultimate limit states of load-bearing capacity (such as flexural and shear capacities) and verification for serviceability limit states (such as crack width ≤ 0.2mm and deflection ≤ span/250); the strength grade of the concrete in the composite layer must match that of the prefabricated base plate, typically not lower than C30.
3. Structural Requirements: The rib height of the prefabricated base plate should not be less than 50mm, and the rib spacing must meet construction requirements; between the composite layer and the prefabricated base plate, shear-resisting steel bars or rough surfaces must be provided to ensure the bonding performance of the interface; temporary supports must be set up during the construction phase to prevent deformation of the prefabricated base plate due to self-weight or construction loads.