Project name: a residential project design unit in Guangzhou: precast components of the third Architectural Design Institute of Guangzhou Design Institute Group Co., Ltd.: laminated plates, precast stairs, precast internal partitions, precast external walls Evaluation criteria such as precast bay windows: evaluation criteria for precast buildings in Guangdong Province DBJ / t15-163-2019 (hereinafter referred to as “Guangzhou standard”) assembly rate: more than 50%.

This section takes floor slab as an example to introduce the design process of laminated slab in detail.

The author ouyangwei project applies the application of precast scheme.

(1) Determine the type of laminated plate ① in order to reduce the workload of on-site hoisting and assembly, the project adopts the method of “large plate” and reasonably reduce the number of secondary beams; ② Follow the principles of reasonable stress, simple connection and convenient construction, adopt the two-way slab form of integral joint, and the joint shall avoid the position with the maximum bending moment in the middle of the span as far as possible.

④ Lap size: in order to prevent slurry leakage at the floor support during construction and pouring, the design strictly considers the lap of 10mm at the support; ⑤ The core tube, toilet and roof slab are cast-in-situ.

Blindness is a taboo in the design of precast buildings.

After determining the floor type, it is mainly to adjust the floor splitting parameters, including the thickness of the precast base plate, chamfer type, splitting size, lap parameters, etc.

If it is not masonry, it can be used as a light partition wall at the toilet and core barrel; ② The toilet board is preferably cast-in-situ.

Bend Loop

Generally, according to the regional characteristics, the design of precast buildings will have local PC design principles, These design principles are the greatest treasure of assembly designers.

Among them, precast concrete structural components are pre adopted below the tower, which are as follows: ① precast laminated plates are adopted for the floors of the second floor and above (on the premise that the score meets the standard, the roof layer is cast-in-situ); ② The stair treads on the second floor and above are precast; ③ The bay windows on the second floor and above are precast; ④ ALC strips are used for internal partition walls on the second floor and above; ⑤ The enclosure walls on the second floor and above are cast-in-situ with aluminum film; ⑥ Integrated kitchen and integrated toilet on the second floor and above (optional).

⑤ If it meets the requirements of standardized design and green construction evaluation, it is excellent, and a total of 3.5 points can be obtained.

▲ click the blue words above to pay attention to the information of PKPM structural force technology project: there are 38 towers in the residential part, and the cast residential building area is about 260000 square meters.

See Table 1 for the calculation details of single residential 1-5#a assembly rate, and see Figure 1 for the assembled building model.

According to article 6.6.2 of technical specification for precast concrete building structures jgj1-2014, the thickness of precast floor is designed to be 60mm and the thickness of cast-in-situ layer is 80mm; ② Floor splitting width: according to article 6.6.5 of technical specification for precast concrete building structures dbj15-107-2016, the maximum width is not more than 3000 and the minimum width is not less than 600mm.

(3) After determining the basic splitting scheme of the floor slab, the deepening design of the laminated slab is completed based on the splitting size of the floor slab and relying on the deepening function of pkpm-pc software; It mainly includes the reinforcement of laminated plate, the design and checking calculation of hoisting and demoulding accessories of laminated plate, and the reservation and embedding of electromechanical points..

In this project, taking into account structural layout, vehicle transportation, factory production and other factors, the splitting size is designed to be between 1300-2700mm; ③ Chamfer size: considering the form of integral joint, the floor slab of the project is only provided with upper chamfer, and the chamfer size is 30 * 30MM.

The assembly rate of single residential 1-5#a reaches 53.1%, which meets the evaluation requirements; Among them: ① the main structure part shall not be less than 20 points, and the main precast components include laminated plates and stairs; ② The score of enclosure wall and internal partition wall shall not be less than 10 points, and the main precast components are ALC light internal partition wall and PC enclosure wall; ③ For the decoration of the kitchen, 6 thin tiles are used to separate the ceiling from the equipment, and the ceiling is used for the decoration of the kitchen; ④ The wide standard requires that PC exterior wall panels and bay windows can belong to precast exterior wall panels, which can be scored in the detailed items.

If the score of horizontal components cannot meet the total score requirements, it can be used as an integrated toilet; ③ The separation of tower pipeline shall not be carried out as far as possible; ④ If the side of precast bay window is shear wall, aluminum film cast-in-situ shall be preferred; ⑤ The precast slab on the roof layer should be cast-in-situ if the fraction allows.

The improvement of efficiency and the design control of the whole process can be well controlled; Before the formal project explanation, let’s talk about the basic principles for the assembly scheme selection of conventional residential projects according to the Guangzhou standard: ① masonry is preferred for the household wall of the tower.

In order to realize less specifications of laminated plates, realize standardized production and meet the requirements of assembly rate, the project considers the combination of equal division and modularization, and realize the optimal solution of floor separation through program automatic calculation; ① Floor thickness: the floor thickness of the project is 140mm.

Figure 11-5#a application of BIM model pkpm-pc of house type precast building to improve design efficiency.

Through pkpm-pc assembly design software, the project can automatically complete the assembly rate statistics and output the assembly rate calculation sheet according to the assembly scheme.

(2) Determine the splitting scheme of the laminated slab.

The rapid statistics of assembly rate meets the requirements of “Guangzhou standard”.

Now let’s take a look at the specific implementation scheme of the actual project: Taking the single residential 1-5#a house type as an example, this paper introduces the implementation of the project in detail.