Prefabricated Concrete House Construction

The construction process of prefabricated concrete houses mainly consists of three stages: factory prefabrication of components, transportation of components, and on-site construction.

Factory prefabrication of components: The main body of the house is pre-cast with various concrete components in the factory, such as ceilings, walls, and bathroom waterproof layers. Taking the China Construction Hailong Intelligent Construction Industrial Park in Shenzhen, Guangdong, as an example, different parts of the house are manufactured in a three-dimensional factory. Scattered components are first produced separately on the second or third floor and then sent to the assembly station for final assembly using welding manipulators and highly automated methods. When making components, workers assemble precision-machined metal steel plates into molds using bolt connectors. After spraying a release agent on the mold surface, they cross-place steel bars and bind them into a mesh framework with steel wires. Connectors are placed at symmetrical positions inside the steel bar mesh, and then concrete is filled in. During pouring, vibrators are used to remove air bubbles, and the surface is smoothed. After that, the components are covered with plastic sheds and heating devices are installed to promote the cement hydration reaction.

Transportation of components: The prefabricated concrete components from the factory are transported to the construction site. This process requires reasonable planning of transportation routes and methods to ensure that the components are not damaged during transportation and to guarantee their quality and integrity.

On-site construction:

• Foundation laying: Similar to general house construction, a foundation needs to be laid before building a prefabricated concrete house. Workers dig a pit about 1 meter deep at the house site. After laying a moisture-proof PE film at the bottom of the pit, they pour "discarded concrete" (waste concrete materials from construction and demolition activities) into the pit as a base. After this layer of discarded concrete, which is more than 10 cm thick, has completely solidified, guide steel plates for positioning the prefabricated concrete piles are installed on it, and the large prefabricated concrete base plates are placed on the guide steel plates.
• Component assembly: Cranes are used to lift the prefabricated concrete house modules, and workers cooperate to accurately position them on the foundation. The components are connected together like building blocks to form a rough house, eliminating the need for on-site pouring and significantly reducing the construction period. For example, at a real estate construction site in Shanghai, tower cranes transport the prefabricated "building blocks" and install them in suitable positions. Each "building block" has a detailed "ID card" including the project name, product model, and production date.