by ▲ click the blue character above to pay attention to the location of PKPM structural force technology project: introduction to the project in xiong’an new area, Hebei Province: relying on a cast-in-situ structure, the following design conditions have been changed: ① the original design is cast-in-situ concrete structure, which is changed to cast concrete structure, and the assembly rate is not less than 50%; ② Change relevant thermal insulation practices in combination with precast buildings and energy-saving and thermal insulation requirements; ③ Green buildings meet the two-star standard.
Project information: select the project 11# building, with 18 floors above ground and 1 floor underground, with a building height of 52.5m and a total building area of 9113.55m2, including 493.51m2 underground building area, 8620.04m2 above ground building area and 488.39m2 floor area.
Figure 1.1 introduction to the author of the project introduction to Zhao Yaoxiang and Yuan Jingwei # 01 # project research objectives this project aims to study the disassembly method of precast buildings and form a set of component disassembly method and deepening design method suitable for assembling integral reinforced concrete structures.
The main contents focus on the research on the separation of vertical and horizontal components of precast concrete structure, the deepening design of precast components, and the deepening research on the joints of precast concrete structure.
Figure 1.2 project model diagram precast building scheme design 01 architectural scheme design architectural scheme from the initial design, each single functional module considers the modularization requirements, and has the basic conditions for the disassembly of precast components.
The basis of standardized design is modular coordination.
On the basis of modularization, modular and serial design methods are adopted, and the principle of “less specifications and more combinations” is followed to meet the requirements of high repetition rate, less specifications and more combinations as far as possible, such as building basic units, connecting structures, components, building components and equipment pipelines.
The basic unit modules of the building are diversified and combined according to the functional requirements, and a multi-level building combination module is established to form a replicable and popularized building monomer.
In the streamline organization of the unit plane of this scheme, the design idea of centralized traffic and separate two households is adopted, and the public pipelines and elevators are arranged in the middle.
Under the condition of meeting the fire protection and other design regulations, the area of the public area is reduced as much as possible, and the occupancy rate reaches 83%.
The structural form of the residential project is shear wall structure.
The residential unit is two units, with a total of 18 floors and 72 households.
Each unit is one elevator and two households.
Each unit is equipped with one elevator and one fire elevator (also barrier free elevator).
The layout plan of the building scheme is shown in Figure 2.1.
Considering the score of precast enclosure wall and internal partition wall, non masonry is adopted for local peripheral protection and internal partition wall of the project.
Figure 2.1 layout plan of the project # 02 # structural scheme design 1) vertical component and auxiliary component splitting.
The splitting range of vertical components is 3 ~ 17 floors of the project.
The splitting components include precast internal and external walls, precast external wall panels, precast internal partition walls, precast bay windows, 18 types of precast external walls and external wall panels, and 14 types of precast internal walls and precast internal partition walls, Precast bay windows are of the same type.
The total number of vertical components in the whole building reaches more than 1400, but there are only 33 types.
In the process of splitting, we should focus on the integration of components and minimize the types of components.
The layout of precast internal and external walls is shown in Figure 2.2.
Fig.
2.2 vertical component splitting layout Fig.
7 Building electromechanical formwork closing 2) horizontal component and auxiliary component splitting horizontal component types include laminated plate, laminated beam, air conditioning board and precast stairs.
In this project, there are only 8 kinds of laminated plates and 16 kinds of laminated beams, and the air conditioning panels and stairs have been standardized.
There are 26 kinds of horizontal members, and the number of horizontal members is about 1700.
The layout of horizontal members is shown in Figure 2.3.
Figure 2.3 layout of horizontal component splitting # 03 structural scheme design the architecture, structure and electromechanical disciplines of the project adopt pkpm-bim software to carry out forward design, and the professional cooperation process is shown in Figure 2.4.
Direct drawing based on BIM model can generate water supply and drainage plan and detail drawing, and the drawing rate can reach 70%.
Figure 2.4 professional collaborative process 1) water supply and drainage pipeline design the pipeline well and toilet area of the project are cast-in-situ, without pipeline separation technology, and the practice of electromechanical pipeline is basically the same as that of traditional cast-in-situ.
The water supply shaft is set in the project, the vertical main pipe, household valve and water meter are set in the shaft, and the pipeline in public area is laid in the cast-in-situ floor to the household.
The horizontal pipes are concealed in the cast-in-situ floor, the vertical pipes are grooved in the wall, the fire pipes are exposed in the stairwell, front room and other public spaces, and the fire hydrants are exposed in the shared front room.
The design of water supply and drainage pipeline is shown in Figure 2.5.
Figure 2.5 water supply and drainage pipeline design 2) the electrical pipeline design project is provided with an electrical shaft, the vertical trunk line and floor public electrical equipment are set in the shaft, the pipelines in the public area are laid in the ceiling of the public area of the standard floor, the household pipelines pass through the steel pipe in the ceiling and enter the cast-in-situ section, and the wall is concealed.
The indoor distribution box and weak current box are installed on the cast-in-situ concrete wall section of the restaurant.
Indoor horizontal pipelines are laid in the cast-in-situ layer of laminated plate, and vertical pipelines are grooved in the wall.
The electrical pipeline design is shown in Figure 2.6.
Figure 2.6 electrical pipeline design 3) heating pipeline design this project is equipped with heating shaft, vertical main pipe and household valve, which are exposed in the shaft, and laid in the cast-in-situ floor of public area to the household.
The indoor water supply and return horizontal pipeline is laid in the cast-in-situ floor of the floor.
Different from the traditional cast-in-situ method, the pipeline needs to reserve joints at the connection between the public areas such as the front room and the indoor pipeline to facilitate on-site installation.
The design of heating pipeline is shown in Figure 2.7..
