The Ministry of Housing and Urban-Rural Development of the People's Republic of China defines the deep foundation pit as follows in the Measures for Safety Management of Dangerous Sub-projects (Jianshi No.200987):
1. Earthwork excavation, support and dewatering works of foundation pit (trough) with excavation depth exceeding 5m (including 5m).
2. Although the excavation depth is less than 5m, the earthwork excavation, support and dewatering project of foundation pit (trough) with complicated geological conditions, surrounding environment and underground pipelines or affecting the safety of adjacent buildings (structures).
Foundation pit engineering mainly includes the design and construction of foundation pit supporting system and earthwork excavation, which is a comprehensive system engineering. It needs the close cooperation of geotechnical engineering and structural engineering technicians. Foundation pit supporting system is a temporary structure, which is no longer needed after the completion of underground engineering construction.
Definition of Deep Foundation Pit: According to the Notice of the Ministry of Construction on Printing and Distributing the Safety Management Measures for Dangerous Sub-projects, a general deep foundation pit refers to a project with an excavation depth of more than 5m (including 5m) or a basement with three floors (including 3m) or a depth of less than 5m, but the geological conditions, surrounding environment and underground pipelines are particularly complicated.
Both foundation pit and foundation trench are used to build buildings, but their plane shapes are different. The foundation pit is square or nearly square, and the foundation groove is longer, sometimes longer.
Foundation pit refers to the foundation pit with the bottom area less than 27 square meters (not 20) and the bottom long side less than three times the short side.
The base groove means that the width of the groove bottom is less than 3 meters and the groove length is more than 3 times the groove width.
A deep foundation pit is generally defined as a project with a bottom area of less than 27 square meters (not 20), a long side of the bottom less than three times the short side, an excavation depth of more than 5 meters (including 5 meters) or more than three floors of the basement, or a depth of less than 5 meters, but the geological conditions, surrounding environment and underground pipelines are particularly complicated. (On the contrary, it is a shallow foundation pit) Thank you very much for your patience. Please adopt it if it helps. Wish you a happy life! thank you