How to standardize the design of prefabricated components? The first technical guideline of Jiangsu Province was released

The development of prefabricated buildings can improve the contribution of the construction industry to the realization of the goal of "carbon peaking and carbon neutrality", which is the only way for the transformation and development of the construction industry. The reporter learned from the Nanjing Municipal Construction Committee that the "Technical Guidelines for Standardized Design of Prefabricated Components of Prefabricated Residential Buildings in Nanjing (Trial)" was officially implemented in May. It is understood that this guideline realizes the unification of standardization and diversification of prefabricated components according to the design method of few specifications and multiple combinations.

According to the Nanjing Municipal Construction Committee, the "Guidelines" innovatively proposes the concept and calculation method of the standardization rate of prefabricated components. Measure the degree of standardization in the design of prefabricated components of prefabricated residential buildings, promote the optimization of the bay and depth of functional spaces in the design stage, and form standardized basic functional units, realize the standardized design of prefabricated houses, meet the design requirements of diversified house types, reduce the number of on-site hoisting, and improve construction efficiency.

In the preliminary research process, after analyzing the specifications and dimensions of basic functional units such as living rooms, bedrooms, kitchens, bathrooms and other common units in actual cases of more than 50 prefabricated residential building projects in Nanjing, it was clearly proposed that the basic functional unit bay size and floor height are used as parameters to set the standardization of components, which weakens the concept of plane standardization and elevation standardization.

The "Guide" is based on three types of prefabricated components: concrete prefabricated composite floor slabs, prefabricated stair slabs and prefabricated shear wall panels, and controls the dimensions and reinforcement specifications of the components to form a standard prefabricated component library. Taking the prefabricated laminated floor as an example, according to the statistics of the types of prefabricated components of common house types, the general standardized floor types determined by the "Guidelines" account for about 70% of the total types of components. It is estimated that the standard prefabricated laminated floor slab can effectively save about 7% of the amount of steel bars without reducing the amount of concrete prefabrication, and at the same time, it can improve the utilization rate of molds in the production process and effectively reduce the production cost.

In recent years, with the emergence of high-assembly rate demonstration projects such as the Nanwai School Project in the Southern New City of Nanjing and the Jiangbei Library, prefabricated buildings have become the main trend of the transformation and development of the construction industry. The introduction of the "Guidelines" will promote the implementation of standardized design results for prefabricated buildings, accelerate the application of prefabricated technologies in actual engineering projects, and drive the overall transformation and upgrading of the construction industry in Nanjing.