Safety Inspection of Prefabricated Panel Houses

The safety inspection of prefabricated panel houses should focus on three core dimensions: structural integrity, the condition of components themselves, and usage and modification situations. The specific inspection points are as follows:

I. Structural Integrity and Foundation Inspection

1. Foundation: Check for obvious settlement marks on the ground around the house, whether there are height differences between indoor and outdoor floors, and observe whether the bottom of the walls has diagonal cracks due to uneven foundation settlement. If such phenomena exist, it may indicate insufficient foundation bearing capacity or the risk of uneven settlement.
2. House Tilt: Stand at a certain distance and visually inspect whether the entire house shows visible tilt or distortion phenomena. Tilt may be caused by foundation problems or overall structural instability, and its severity needs further evaluation.

II. Special Inspection of Core Components

1. Prefabricated Floor Slabs:
   • Cracks at the Bottom of the Slab: Observe whether there are horizontal through-cracks on the ceiling (bottom of the prefabricated slab) or obvious cracking at the joints between slabs. Such cracks may be caused by uneven stress on the slab or material aging.
   • Deflection Deformation: Check whether there are obvious signs of downward bending or sinking in the middle of the slab, which may reflect insufficient bearing capacity of the slab or long-term overloading.
   • Damage at the Ends: Examine the positions where the prefabricated slabs rest on the walls to confirm whether the concrete is loose, crumbling, or whether the steel bars are exposed and rusted. Damage at the ends will weaken the connection strength between the slab and the wall.
2. Load-Bearing Walls:
   • Stress Cracks: Focus on inspecting vertical cracks, diagonal cracks on the load-bearing walls, as well as cracking and downward pressure deformation above the lintels of doors and windows. Such cracks may be caused by excessive stress on the walls or foundation settlement.
   • Wall Weathering: Observe whether the bricks or masonry at the bottom of the walls are severely weathered, spalled, or loose, which may reduce the bearing capacity of the walls.
   • Structural Measures: Confirm whether the house is equipped with ring beams and constructional columns. For brick-concrete prefabricated panel houses of 3 stories or more, if such structures are absent, the overall seismic resistance and safety will be significantly reduced.
3. Node Connections:
   • Lap Length: Check whether the support length of the prefabricated slabs on the brick walls complies with the specifications (should not be less than 80mm). Insufficient support may lead to slab slippage or collapse.
   • Tie Conditions: Check whether the corners and junctions of the walls are separated or have cracks. Insufficient tie conditions will affect the overall structural integrity.

III. Inspection of Unauthorized Modifications and Usage Environment

1. Removal or Modification of Load-Bearing Walls: Verify whether the house has had load-bearing walls removed without authorization, doors or windows opened in load-bearing walls, or the size of openings enlarged. Such actions will directly weaken the structural bearing capacity.
2. Unauthorized Additions (Increased Load): Check whether additional floors have been built on the roof without authorization, mezzanines added, or whether heavy equipment or large water tanks have been placed on the floor slabs. Overloading may lead to damage to the floor slabs or walls.
3. Change of Use: If a house originally designed as a residence is changed to a place with a large number of people (such as a restaurant or KTV), the significant increase in live load may lead to safety accidents.

Precautions: Preliminary inspections cannot replace professional house safety appraisals. General hidden dangers should be checked by professional technicians; if the house shows obvious dangers, it is necessary to entrust a qualified appraisal unit to conduct inspections and handle it according to the appraisal results.