This project is one of the key livelihood projects in Zhanjiang City. It aims to meet the housing needs of low- and middle-income social workers, such as cleaners and bus drivers, by providing them with high-quality public rental housing. The goal is to enhance the happiness of workers and reflect social equity.
The project is located on the south side of Dongsheng Road in Chikan District, Zhanjiang City, with Futian Road to the east and Huatian Road to the west. The site is rectangular in shape, 175 meters long from east to west, and 84 meters wide from north to south, with a flat terrain. The northern part is a water purification plant, while the east, south, and west sides are high-rise residential areas that have already been built. The northern side faces the bay with good landscape visibility, and the surrounding transportation is convenient.
The planned land area for the project is 24,885 square meters, with a total construction area of 68,606 square meters. Three high-rise tower residential buildings are arranged along the south side of Dongsheng Road in a staggered pattern. The bottom three floors are commercial facilities for supporting services. The residential products mainly consist of small units of 45 square meters and 60 square meters, with good natural ventilation, lighting, and landscape orientation.
This project is one of the important pilot projects for steel structure assembled housing of the Ministry of Housing and Urban-Rural Development and the Housing and Construction Department of Guangdong Province. It does not adopt traditional reinforced concrete structures, but instead uses steel structures and prefabricated components for assembly.
The architectural layout is designed in accordance with the characteristics of the steel structure system, using a design method that combines various functional modules and module combinations. The modules should be optimized and combined to meet functional requirements and structural layout requirements. The layout is regular, flat, and uses a symmetrical arrangement. Elevator and equipment shafts are independently and centrally located, while space partitioning is coordinated with the structural beam and column layout, and the spatial layout considers the arrangement of the structural lateral force resistance system.
The design of the apartment layout follows the principles of standardization and serialization, using standardized apartment designs with a large open-plan layout to provide flexibility and variability in interior space while meeting the requirements for standardization, modularization, serialization, and combination.
The architectural facade design conforms to the climate characteristics of Zhanjiang city, using a combination of standardization and diversity. Integrated wall panels with good thermal insulation performance and matching decorative materials are used to meet durability requirements. Common parts such as exterior wall panels, doors and windows, balcony panels, curtain walls, air conditioning panels, sun shading facilities, and decorations are designed with standardization in mind, and the shape of the building facade is uniform and modern with a simple style.
The implementation of the steel structure assembly construction system conforms to the requirements of green, low-carbon, energy-saving and environmental protection, and conveys the concept of sustainable development throughout the entire life cycle of the building.
The project is located in a high wind pressure area that is frequently affected by typhoons. The design of the high-rise steel structure assembly residential system faces the following challenges:
(1) The adaptability and variability of small unit products with steel structure system.
(2) Structural comfort of high-rise buildings in high wind pressure areas.
(3) Performance-oriented structural system.
(4) Standardized assembly design.
(5) Integrated green construction with design, construction, operation, and cost control.
Adaptability and versatility of small-sized units to steel structural systems
To meet the adaptability of small-unit products with a steel structure system, we have selected a point-type layout through a comparison of floor plan schemes based on the requirements of the building's functional use, structural safety indicators (such as inter-story displacement angle and comfort), and economic indicators. The advantage of a point-type layout is that it has a complete and square outline with minimal concave-convex changes, which is conducive to the arrangement of structural support.
Adaptable unit layouts to accommodate diverse usage needs
Under the steel structural system, the vertical structure is optimized to ensure that there are no structural walls or columns inside the apartment, providing better adaptability and flexibility for future space renovation and enhancement. Three standardized apartment layouts are designed with reasonable sizes, good lighting, centralized kitchen and bathroom, and convenient pipeline layout. The apartment layouts can be combined, such as combining a 60㎡ and a 45㎡ apartment to create a new 105㎡ apartment. By changing the location of the partition walls inside the apartment, the layout can be transformed from a one-bedroom to a two-bedroom, providing a flexible space pattern that can adapt to different numbers of residents and functional needs.
Design of Accessible Housing with Supporting Facilities
Taking advantage of the flexibility of the adaptable layout, the design adjusts the size of the kitchen, bathroom, and corridor to reduce one bedroom, providing a barrier-free single-person unit that meets the needs of people with disabilities.
steel frame-concrete core tube structural system
To meet the construction of the assembled steel structure and ensure the structural comfort in high-wind areas, the point-type plan was first determined through plan comparison. Then, using the YJK software to compare the steel frame-core concrete tube structure, steel frame-steel plate shear wall, and other structures, the steel frame-core concrete tube structure had the smallest peak wind-induced acceleration value and required less steel. After comparing three or four different structural layouts, the option with the smallest peak wind-induced acceleration value and better economic indicators was selected. Finally, using analysis of vibration frequency, vibration acceleration, and vibration duration with YJK model, Midas model, and wind tunnel testing, the scheme that satisfied wind comfort was selected. The final decision was made to adopt the steel frame-core concrete tube structure system.
Vertical structural components
The vertical structural components adopt steel-concrete columns and aluminum formwork for cast-in-situ concrete core, which enhances the comfort and practicality of the building's space. The steel-concrete columns also meet the requirements of prefabricated construction.
Horizontal Structural Components
All beams outside of the core tube for horizontal structural components are made of steel beams, while the floor slabs and balcony slabs are made of reinforced steel truss floor slabs, and the air conditioning slabs use prefabricated aluminum alloy frameworks.
enclosure wall system
The enclosure wall system adopts the approach of using Autoclaved Lightweight Concrete (ALC) panels, aluminum curtain wall, and aluminum alloy doors and windows, integrated with thermal insulation and decorative finishes.
nternal partition wall system
The interior partition wall system uses ALC panels or aerated concrete blocks for partition walls between units, and aerated concrete blocks for bathrooms, pipe shafts, and stairwells inside the core.
exterior wall waterproofing
For our building's exterior waterproofing design, we have adopted a double waterproofing system combined with an air gap. We use sealed aluminum panels as the first layer of exterior waterproofing, followed by a 1.2mm thick polymer waterproof coating as the second layer, which is used to protect the wall panels. The air gap between the aluminum panels and ALC wall panels is utilized as a waterproof barrier to better isolate the wall from rainwater. These multiple waterproofing measures effectively prevent penetration and leakage.
Standardized floor plans and unit types
Each floor plan is standardized, with a regular layout and load-bearing walls that connect from top to bottom. The building form has no significant irregularities and meets both functional and seismic safety requirements. Each building is constructed by combining and assembling standard unit types, achieving standardized unit layouts.
Modular standardization is in coordination with the prefabricated building system
The building design adopts a unified module coordination dimension, which complies with the current national standard "Building Module Coordination Standard" GB/T50002-2013. The layout adopts a modular design, with the living room and bedroom's span designed according to the module, and the kitchen and bathroom designed according to modules. The wall panels are combined with a 600mm width module of the ALC panels, and window openings are set at appropriate positions. The height of door and window openings is consistent, and the width of the same type of room is consistent. The window gridding and opening width are also consistent.
Standardization of component-to-component connection nodes
In different house types and locations, standardized prefabricated components such as steel columns, steel beams, precast wall panels, and air conditioning panels are used to achieve maximum standardization of prefabricated components. The connection nodes of prefabricated components are standardized to achieve uniform installation methods in the later stage.
本项目BIM技术主要应用于钢结构安装、装配式设计、管线碰撞检测等内容。设计中制定 BIM 实施方案，按照BIM实施方案开展BIM应用；创建与施工范围一致的深化设计模型、施工模型、竣工模型；利用深化设计模型、施工模型开展BIM应用，模拟施工方案、优化施工方案、施工方案交底；利用模型与其他相邻工程开展协同，消除碰撞、合理划分施工界面；根据设计变更图纸更新施工模型。
The BIM technology in this project is mainly applied to steel structure installation, prefabricated design, and pipeline clash detection. A BIM implementation plan was developed in the design phase and BIM applications were carried out according to the plan. Deep design models, construction models, and completion models were created to match the scope of construction. BIM applications were carried out using the deep design models and construction models to simulate and optimize construction schemes, and for construction coordination. Collaboration with adjacent projects was carried out using the model to eliminate conflicts and rationally allocate construction interfaces. The construction model was updated according to the design change drawings.
During the detailed design phase, the steel structure is deepened and prefabricated for assembly. The construction process of the steel components is simulated, and the BIM model is used for prefabrication and assembly of bars, node connections, bolts, and welds to assist in material cutting. Collision checks and clearance analyses are performed, and openings are checked and reserved, and various professional designs are carried out based on the BIM model.
During the construction process, BIM is used for site layout, progress control, cost management, simulation of construction plans and processes, construction guidance, material control and optimization, prefabricated machine rooms, drone applications, VR technology applications, and other tasks.
Structural Performance Monitoring
In terms of monitoring structural indicators, the wind-induced acceleration of high-rise steel residential buildings will be monitored to fill the domestic gap in this field. The numerical simulation, wind tunnel test, and structural monitoring data will be cross-compared to guide the subsequent steel residential structure design and optimization. The structural health monitoring system adopts a cloud-based monitoring platform, which sends the data collected by on-site sensors to the cloud platform for analysis, warning, and evaluation through remote instructions.
The use of steel structure building materials and prefabricated construction, combined with BIM technology, enables green materials and construction practices. Compared to traditional construction, it reduces water usage by 80%, material waste by 20%, construction waste by 80%, and achieves an overall energy saving of 70%. It also reduces building maintenance costs by 95%, and allows for 100% recyclable or degradable steel structure materials.