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This post was last edited by hesonchang214 on 2016-11-18 at 16:12. According to Article 12.1.1 of the \"Technical Code for Concrete Structures of High-Rise Buildings\" JGJ 3-2010, high-rise buildings should preferably have basements. High-rise buildings are more sensitive to horizontal loads; compared to ordinary multi-story buildings, they require better anchoring properties. Their strength, stability, and functionality all demand that the foundation of high-rise buildings have a greater depth of burial. Constructing a basement using this buried depth is more cost-effective. Code for Design of Building Foundation GB 50007-2011: 5.1.2 On the premise that the requirements for foundation stability and deformation are met, when the bearing capacity of the upper layer of soil is greater than that of the lower layer, it is advisable to use the upper layer of soil as the bearing stratum. Except for rock foundations, the foundation depth should not be less than 0.5 m. 5.1.3 The embedment depth of the foundations for high-rise buildings shall meet the requirements regarding foundation bearing capacity, deformation, and stability. For high-rise buildings built on rocky foundations, the depth of the foundation should meet the requirements for slip resistance stability. \"Technical Code for Concrete Structures of High-Rise Buildings\" JGJ 3-2010: 12.1.8 The foundation shall have a certain embedment depth. When determining the burial depth, factors such as the height and shape of the building, the quality of the foundation soil, and the seismic design intensity should be taken into comprehensive consideration. The foundation burial depth can be measured from the outdoor ground level to the bottom surface of the foundation, and it should comply with the following requirements: 1 For natural foundations or composite foundations, 1/15 of the building height can be used as a reference ； 2 pile foundations; the pile length is not considered, and 1/18 of the building height can be used. When a building uses a rock foundation or effective measures are taken, and provided that the requirements regarding foundation bearing capacity and stability as well as those specified in Article 12.1.7 of these regulations are met, the foundation depth may be relaxed appropriately compared to the provisions in Paragraphs 1 and 2 of this article. When the foundation is prone to sliding, effective anti-sliding measures should be taken. Purpose of specifying the foundation burial depth: 1. Article 5.1.3 of the \"Code for Design of Building Foundation Foundations\" GB 50007-2011 states that the burial depth of foundations in high-rise buildings shall meet the requirements regarding foundation bearing capacity, deformation, and stability. For high-rise buildings built on rocky foundations, the depth of the foundation should meet the requirements for slip resistance stability. By constructing a basement, the lateral pressure of the soil can be utilized to prevent the structure from sliding or toppling under horizontal loads, thereby reducing the overall tilting of the structure ； Excavating the basement removes a large amount of soil, thereby reducing the additional pressure on the foundation and increasing its load-bearing capacity. 2. Once the foundation has a certain depth of burial, the passive earth pressure on the front and rear walls of the basement, along with the friction force on the side walls, exert a limiting effect on the movement of the foundation; this also helps to keep the pressure at the base of the foundation more uniform. 3. A certain burial depth of the foundation is beneficial for seismic resistance, as it can reduce the seismic response of the superstructure. Investigations on earthquake damage show that high-rise buildings with basements suffer less damage, and having a basement is beneficial for increasing the bearing capacity of the foundation as well as for enhancing the structure’s resistance to overturning. 4. For multi-story and high-rise buildings, constructing a basement can reduce the additional stress on the foundation, thereby decreasing the amount of settlement of the foundation. 5. Meet the requirements for civil air defense basements as specified in the civil air defense discipline. 6. The inclusion of basements in modern high-rise buildings is often also required by the functional needs of the building. Using basements as garages, storage spaces, and for other purposes can help address the shortage of construction land in the process of urbanization. 7. It can enhance the overall stability of buildings on soft soil foundations. Soft soil has a high degree of compressibility; by removing this layer of soil and placing the foundation on a stable bearing stratum, uneven settlement of the building can be reduced, thereby improving its overall stability.