Production Process of House Prefabricated Slabs
The production process of house prefabricated slabs mainly includes steps such as mold preparation, steel reinforcement framework laying, concrete pouring, steel strand treatment, curing, and post-treatment. Details are as follows:
First, mold preparation is carried out. Workers use steel plates to form the mold and secure its shape by tightening screws. Subsequently, a mold release agent is sprayed on the inner wall of the mold. The purpose of this step is to prevent the subsequently poured concrete from adhering to the mold, ensuring that the surface of the prefabricated slab is intact during demolding. The mold dimensions need to be precisely made according to design requirements to ensure uniform specifications of the prefabricated slabs.
Next, the first layer of steel reinforcement framework, namely distribution bars, is laid. The size of this framework must fully match the internal space of the mold, forming the bottom support structure of the prefabricated slab. The function of the distribution bars is to disperse the load and enhance the overall integrity of the concrete structure. Then, a concrete layer about four centimeters thick is poured on the steel reinforcement framework as the base layer of the prefabricated slab.
Before the initial setting of the base layer concrete, a large foam board with a thickness of 15 centimeters is placed. The foam board occupies half of the volume of the prefabricated slab and is connected and fixed internally with iron hooks to ensure that it does not shift during the concrete pouring process. The function of the foam board is to reduce the self-weight of the prefabricated slab while improving its thermal insulation performance.
Subsequently, the second layer of steel reinforcement framework is laid, and a dozen or so steel strands with extremely high tensile strength are threaded through as load-bearing bars. Using the pre-tensioning method, special equipment is used to stretch the steel strands to their ultimate strength, generating pre-stress. This step counteracts the tensile stress caused by later loads by pre-compressing the concrete, thereby significantly improving the crack resistance and load-bearing capacity of the prefabricated slab.
After the steel reinforcement treatment is completed, the second layer of concrete is poured to cover the entire structure. During the pouring process, a vibrating rod is used to vibrate and expel air bubbles inside the concrete, avoiding cracking or strength reduction due to pores. Then, the prefabricated slab is lifted and transported to the basement for steam curing. Through a high-temperature and high-humidity environment for 4 hours, the hydration reaction of the concrete is accelerated, enabling it to quickly reach the designed strength.
After curing is completed, the pre-stress of the steel strands is released, and the prefabricated slab is demolded by hooking its four corners with a gantry crane. Finally, an angle grinder is used to cut off the excess steel bars at both ends of the prefabricated slab to complete the surface finishing. For more complex giant prefabricated slabs, the production process will be extended to a hundred-meter-scale production line, using professional mechanical vehicles to pull the steel strands and setting fixed supports every ten meters to ensure structural stability.
