Jize Cement Prefabricated House Design

The design of cement prefabricated houses in Jize should be systematically planned from three aspects: pre-design conditions, structural systems and component splitting, and node connection design.

Determination of Pre-design Conditions and Basic Parameters It is necessary to clarify key parameters such as seismic fortification intensity, basic wind pressure, and snow load by considering local climate, geological conditions, and building purposes. For example, two-story rural self-built houses are usually fortified to a magnitude of 7, with a basic wind pressure of 0.4 kN/m², a floor live load of 2.0 kN/m², and a roof live load of 0.5 kN/m². The building modulus is uniformly based on 300 mm, with options for bay widths of 3.6 m, 3.9 m, and 4.2 m, depths of 4.5 m or 5.1 m, and floor heights of 2.8 m or 3.0 m. Unifying the modulus can reduce the variety of components, improve mold turnover rates, and lower production costs.

Selection of Structural Systems and Splitting of Prefabricated Components The structural system should preferably adopt an assembled monolithic concrete frame structure, with pure frame structures recommended for buildings up to three stories. Columns, beams, and slabs are all prefabricated, with the node areas cast with concrete afterward to form an integral structure. Specific splitting rules are as follows:

• Columns: Split one per floor, with common cross-sections of 400 mm × 400 mm or 500 mm × 500 mm;
• Beams: Split main beams at mid-span, with cross-sections of 300 mm × 600 mm, and secondary beams with cross-sections of 250 mm × 500 mm;
• Floor Slabs: Use composite slabs, with a prefabricated base slab thickness of 60 mm, a cast-in-place layer of 80 mm, and a total thickness of 140 mm;
• Other Components: Stairs, balconies, and air conditioning panels are all prefabricated. All components should weigh between 3 and 5 tons and have dimensions not exceeding the transportation width limit of 2.5 m and height limit of 4 m to ensure transportation and lifting feasibility.

Node Connection Design Node connections are the core of prefabricated houses and must be verified through finite element analysis and full-scale factory tests to ensure strength not lower than that of the components themselves:

• Column-to-Column Connections: Use sleeve grouting connections, with vertical reinforcement reserved at the top of the lower column and grouting sleeves embedded at the bottom of the upper column. High-strength grout is injected during installation to form continuous load-bearing reinforcement;
• Beam-to-Column Connections: Achieved through a corbel plate with post-cast concrete. The prefabricated beam end is reserved with a slot, placed on temporary supports at the side of the column. The bottom reinforcement of the beam is welded to the embedded parts in the column, with the upper reinforcement lapped in the node core area, and post-cast with C40 micro-expansion concrete;
• Slab-to-Beam Connections: The胡子筋 (hooked reinforcement) at the slab end extends into the post-cast strip at the side of the beam to achieve reliable anchoring. All connection nodes must meet seismic and load-bearing requirements to ensure structural integrity.