How to Make Prefabricated Slabs for House Foundations

The production of prefabricated slabs for house foundations must strictly adhere to material ratios and process flows, and appropriate plans should be selected based on foundation conditions during construction to ensure standardized operations.

I. Production Process of Prefabricated Slabs

1. Material Preparation
   The core materials include concrete, steel bars, and thermal insulation materials (such as foam). Concrete should be mixed according to the designed strength grade. Steel bars are selected as a combination of distribution bars and load-bearing bars (steel strands), with load-bearing bars woven from steel wires to enhance tensile strength. Additionally, mold release agents, steel plate molds, and pouring equipment such as semi-air tracks or tankers are required.

2. Mold Production and Steel Bar Arrangement
   Weld steel plates to form enclosures, secure them with screws at the corners, and then spray mold release agents to prevent concrete adhesion. Steel bars should be erected according to the design drawings: distribution bars are evenly laid at the bottom of the mold, and load-bearing bars are cross-tied to form a grid, ensuring that the load-bearing capacity meets the standards.

3. Concrete Pouring and Curing
   Pour concrete into the mold using a semi-air track or tanker, and vibrate it to eliminate air bubbles. After pouring, cover it with a moisture-retaining film and let it stand until the concrete initially sets. Then, remove the mold and continue curing until the designed strength is reached (usually 7-14 days), maintaining a stable environmental humidity during this period.

II. Construction Process

1. Foundation Preparation
   Clear debris from the site, measure and set out according to the design drawings to determine the dimensions and location of the foundation. If the foundation contains groundwater, a bottom waterproof layer should be constructed first. If a ground beam is required by the design, it should be poured and cured in advance until the strength meets the standards.

2. Prefabricated Slab Installation
   Transport the prefabricated slabs to the site, assemble them according to the drawings, and adjust their positions to avoid misalignment. Fill the gaps between the slabs with concrete to ensure a tight connection. In scenarios such as rural villas, an elevated moisture-proof method can be adopted: after laying the prefabricated slabs, an elevated layer is formed, and filling the gaps provides significant moisture-proof and insect-proof effects.

3. Top Layer Pouring and Curing
   Pour a cement layer with a thickness of more than 10 centimeters on the surface of the prefabricated slabs, vibrate it flat, and then cover it with a moisture-retaining film. During curing, keep the environment dry and ventilated, avoid external impacts, and ensure the stable growth of concrete strength.

III. Applications in Special Scenarios

1. Brick Formwork Prefabricated Slabs
   Suitable for building foundation construction: use bricks to build formwork and apply cement mortar on the surface to form a flat supporting surface. The construction steps include foundation compaction, brick formwork construction (thickness ≥ 120mm), and mortar plastering, ensuring that the perpendicularity and flatness meet the specifications.

2. Elevated Floor Construction
   In humid areas or rural villas, prefabricated slabs can be laid on ground beams to form an elevated floor, with a recommended height of 30-50 centimeters. After filling the gaps between the slabs with concrete, a floor can be laid or it can be directly used as a moisture-proof layer, providing both ventilation and insect-proof functions.

IV. Precautions

1. Material and Process Standards
   The strength of concrete, specifications of steel bars, and performance of thermal insulation materials should comply with national standards such as GB 50204 "Code for Acceptance of Construction Quality of Concrete Structures".

2. Measurement and Stability Control
   Before installation, verify the dimensions and elevations of the foundation. Positioning pins or steel bar connectors should be set at the joints of prefabricated slabs to prevent displacement.

3. Curing Environment Management
   During curing, avoid sudden temperature changes (e.g., cover with an insulating layer in winter) to prevent concrete cracking; in summer, spray water regularly to maintain moisture and ensure uniform strength development.