How to Place Prefabricated Floor Slabs in a House
The placement of prefabricated floor slabs in a house should be determined based on the span of the house, with the simplest and safest method being to build horizontally in the direction of the smaller span. Here are the specific operational points:
1. Principle for selecting the span direction
The placement direction of prefabricated floor slabs in a house should aim to 'reduce pressure and lower the risk of cracking'. Typically, rural houses are wider than they are long, and the north-south span of interior small rooms often exceeds the east-west span. Therefore, the floor slabs should be placed horizontally in the direction of the smaller span (e.g., east-west). This layout ensures more even distribution of forces on the floor slabs, preventing structural cracking caused by excessive pressure at a single point leading to foundation settlement or vibration. If the house has an extremely small span (e.g., 2 meters long and 3 meters wide), the floor slabs can be placed either horizontally or vertically, but it is generally recommended to prioritize horizontal placement to maintain consistent structural stability.
2. Adjustment logic for special scenarios
When the difference in spans between directions is not significant, adjustments should be made based on actual usage needs. For example, if the east-west span of a room is only 0.5 meters smaller than the north-south span and space needs to be reserved for pipes or wiring, functional needs can be prioritized, but structural strength should be compensated for by adding support points or reinforcing beams. Additionally, if the house has protruding structures (e.g., balconies, eaves), the span of that area should be calculated separately to prevent floor slab deformation caused by uneven local forces.
3. Installation specifications for prefabricated composite slabs
For prefabricated composite slabs (composed of a prefabricated base slab and a cast-in-place layer), special lifting equipment (e.g., lifting steel beams) should be used during installation to ensure that the lifting points bear force simultaneously. During the lifting process, the floor slab must be kept level to prevent internal steel bars from twisting or concrete cracks caused by tilting. If the floor slab is large (e.g., exceeds 6 meters), temporary supports should be added at the mid-span position and removed after the cast-in-place layer has solidified to prevent deflection caused by self-weight during construction.
4. Quality inspection after construction
After the floor slabs are placed, check whether the joints are tight and the support points are stable. If any cracks or exposed steel bars are found at the edges of the floor slabs, they should be replaced immediately; if the joint width exceeds 5 millimeters, it should be filled and leveled with high-strength mortar. Additionally, monitor the house's settlement data, and if the monthly settlement exceeds 3 millimeters, suspend subsequent construction and investigate foundation issues.
