Usage Methods of Prefabricated House Slabs

The usage methods of prefabricated house slabs should follow the following standardized operations according to different types and construction scenarios:

I. Placement Direction of Prefabricated Slabs in Rural Self-built Houses The placement direction of prefabricated slabs should be determined based on the span of the house. It is preferable to build horizontally in the direction with the smaller span, as horizontal floor slabs can withstand greater pressure and offer higher structural stability during foundation settlement. For example, if the horizontal span of the house is 4 meters and the vertical span is 6 meters, the prefabricated slabs should be laid horizontally along the 4-meter direction. This principle is based on mechanical principles, as horizontal laying can disperse the load and reduce the risk of cracking caused by uneven foundation settlement.

II. Construction Techniques for Prefabricated ALC Wall Panels

1. Site Preparation: Before construction, clean the proposed installation area to ensure the ground is flat and solid, preventing wall panel deformation due to an uneven base layer.
2. Vertical Joint Control: During installation, ensure that the width of the vertical joint after extrusion is approximately 5 millimeters and consistent from top to bottom. After grouting, check if the joint is fully filled; if there are any voids, repair them immediately to prevent water seepage or cracking later.
3. Flatness Adjustment: Use a 2-meter leveling ruler to check the wall flatness. If the deviation exceeds 3 millimeters, adjust it slightly with a special pry bar to ensure the wall verticality meets the specifications.
4. Panel Bottom Treatment: Clean the working surface at the bottom of the ALC panel, removing dust, oil, and other debris. Use a narrow trowel to push the mortar to the other side of the panel joint until it overflows, and ensure the joint is fully filled without any omissions after smoothing both sides.
5. Wooden Wedge Repair: After the mortar reaches its strength (approximately 7 days), remove the wooden wedges and repair the filled positions with the same type of cement mortar to prevent structural loosening caused by wooden wedge decay.
6. End Connection: Apply mortar on both sides of the end of the installed panel, and fill the groove of the panel to be installed with mortar to half its height to enhance the connection strength between panels.

III. Key Points for Installation of Prefabricated Slab Formwork

1. Anti-leakage Measures: Before lifting the prefabricated slabs, paste sponge strips around the aluminum formwork C-groove on the top plate of the formwork to prevent mortar leakage during concrete pouring, which could affect the structural density.
2. Support Re-measurement: Check if all supports are in full contact with the ground. After lifting, re-measure the stability of the supports, focusing on detecting the five-point extreme difference (i.e., the maximum height difference) and levelness of the aluminum formwork top plate joists to prevent structural deformation caused by support sinking.
3. Post-construction Treatment: Before decoration, chisel the positions where mortar has leaked, adjust the flatness of the post-pouring strip formwork and wooden formwork support system to ensure the quality of the subsequent construction surface layer.

The above operations should strictly follow construction specifications and adjust details according to the actual situation on site to ensure that the prefabricated slabs meet the design requirements in terms of structural safety, waterproof performance, and durability.