Prefabricated Structural House Inspection Plan

The inspection plan for prefabricated structural houses should be systematically carried out from two aspects: inspection content and methods, in accordance with relevant standards, to ensure the structural safety of the houses.

I. Inspection Basis

Inspections must strictly adhere to national and local standards, including the "Technical Standard for Inspection of Building Structures" (GB/T 50344-2019), the "Code for Design of Concrete Structures" (GB 50010-2010, 2015 edition), the "Code for Design of Masonry Structures" (GB 50003-2011), and other general standards, as well as the Beijing local standard "Standard for Comprehensive Safety Appraisal of Building Structures" (db11/t 637-2024). These standards define the inspection scope, technical requirements, and evaluation methods, providing a scientific basis for inspection work.

II. Inspection Content

1. Inspection of Damage and Defects in Upper Structural Components

   • Inspection of Beam Corrosion: Focus on observing whether beams exhibit exposed reinforcement corrosion. Corrosion can reduce the cross-sectional area of steel reinforcement and decrease bond strength, affecting structural load-bearing capacity.
   • Inspection of Connection Reliability: Check whether the connections between the roof and walls, and between beams and slabs, are secure. Connection failures may pose a risk of local collapse.
   • Monitoring of Cracks and Deformations: Record the width, length, and direction of cracks on the surface of components, and assess whether deformations exceed permissible values specified in the standards.

2. Quality Inspection of Prefabricated Components

   • Geometric Dimension Inspection: Measure parameters such as the length, width, and height of components. Deviations must comply with design requirements to avoid installation difficulties or uneven structural loading due to dimensional errors.
   • Inspection of Appearance Quality: Identify surface defects such as cracks, bubbles, and corrosion. Defects may reduce the durability of components or induce stress concentrations.
   • Material Property Testing: Test the compressive strength of concrete, tensile strength of steel reinforcement, and corrosion resistance through sampling to ensure material strength meets design standards.
   • Inspection of Connection Performance: Evaluate the strength, stability, and waterproof performance of node connections, focusing on bolt tightening force, welding quality, and aging of sealing strips.

3. Structural Safety Assessment

   • Assessment of Renovation Rationality: Analyze whether the structural configuration of added areas is reasonable, such as whether additional loads exceed the load-bearing capacity of the original structure.
   • Analysis of Load Transfer Paths: Check whether the arrangement of load-bearing components (such as columns and walls) is reasonable to ensure that vertical loads can be effectively transferred to the foundation.

III. Inspection Methods

1. Non-Destructive Testing

   • Ultrasonic Testing: Utilize the propagation characteristics of sound waves in components to locate internal voids, cracks, and other defects, suitable for evaluating the internal quality of concrete components.
   • Radiographic and Infrared Testing: Detect internal structures and surface temperature anomalies of components through radiographic penetration or infrared thermal imaging technology, aiding in the judgment of defect locations.

2. Destructive Testing

   • Sampling Tests: Cut samples from components for tensile and compressive tests to obtain actual material strength parameters, providing direct evidence for structural safety assessment.
   • Local Destructive Testing: Conduct small-scale destructive tests at critical locations to verify the reliability of connection nodes or complex structures.