Secondly, the manufacturer of components and fittings is relatively remote from the construction site.

First, the production scale is small.

The application of BIM and other advanced technologies in the construction stage of precast buildings can effectively control the time of on-site temporary facilities and large machinery entering and leaving the site, and assist managers to control the overall construction progress.

At the same time, the standardized degree of components and parts is not high, and the molds should be customized according to the actual situation of the project.

In the face of a large number of components with different sizes, it is difficult to effectively classify them, nor can they be transported in a large number of centralized ways, so they are forced to use bulk transportation, resulting in higher transportation costs for precast buildings.

However, the demand for BIM talents in China continues to grow, and there is a shortage of BIM professionals, which hinders the application of related technologies.

Although there are some mature experiences and standards abroad for reference, the development of precast buildings in China needs to take into account the national conditions and follow the road consistent with the development of precast buildings in China.

(2) At the stage of production of precast buildings with small production scale and low specialization, a large number of components and fittings need to be processed in factories.

In the production process, members are often demoulded prematurely, cured insufficiently or the thickness of the protective layer is not enough, which leads to the failure of the member strength to meet the use requirements, resulting in repair costs, and may even lead to the collapse of the member, increasing the safety costs.

Secondly, the specialization of production workers is not high.

At present, it is difficult to mass produce precast components and fittings with low specialization of workers, and it is difficult to effectively control the production cost of precast buildings.

First of all, the design scheme does not implement the assembly design thinking.

Secondly, it is difficult to flexibly apply advanced technologies in the construction stage of precast buildings.

Due to the large difference in the shape of cast building components, the transportation mode in China is different from that in foreign countries.

(1) Low degree of design standardization In China, precast buildings started late, which caused the problem of low degree of design standardization due to various reasons.

At the same time, the lack of professional transport personnel also leads to low transport efficiency and high transport costs.

The arrangement of transport vehicles, on-site temporary storage, secondary handling and transportation distance and other factors will affect the transportation cost of precast buildings.

At present, the mainstream design idea of the construction unit is to take the cast-in-situ method as the basis, then split the components, and finally deepen the processing of the components.

At present, the design unit lacks the flexible application of the current relevant codes and standards, and needs to understand the codes and standards and design reasonably according to the actual situation of the project.

Thread Swivel Eye

In addition, compared with traditional buildings, grouting workers, embedded workers, component assemblers and other new types of work required for the construction of precast buildings are in short market demand, and their salaries are high.

Therefore, the amortization cost of assembly line equipment and molds is large, and it is difficult to achieve batch production.

First of all, China mainly adopts bulk transportation.

This easily leads to large differences in the shapes and types of components after splitting, which makes it difficult to carry out mass production and transportation.

Secondly, we did not fully understand the norms and used living norms.

The industrialization management mode in the production stage of precast buildings is not mature, the mobility of industrial workers is large, and there is a lack of high-quality and highly skilled talents, which affects the qualification rate of finished component production.

(3) The transportation process of assembled buildings with long transportation distance and low efficiency includes: loading and unloading of transport vehicles, development of transportation routes, and on-site storage.

Because traditional buildings often use cast-in-situ construction, the production scale of precast components is small.

Most assembly type component enterprises select sites in the suburbs to save land costs, resulting in long transportation distance and increased transportation costs.

The authors are Li Hao, Chen Xiaohong and Gao Yujie, edited by “Building Economy and Management”…

First of all, the number of precast building components is large, and the requirements for mechanization, refinement and collaboration of component installation are higher.

This article is excerpted from the “Research on Difficulties and Countermeasures of Cost Control of Fabricated Buildings” in Building Economy, Issue S1, 2022.

(4) High requirements for construction technology, flexible application of lack of advanced technology, high requirements for construction technology of precast buildings, and the application of advanced science and technology is still in the exploration stage, leading to difficulties in cost control in the construction stage of precast buildings.