The Surface Settlement Predict Method Of Excavation

Along with the development of underground space and the increase of density of surrounding constructions, deep excavations are becoming more and more, the depth and dimensions of excavation foundations are becoming larger and larger. Urban deep foundation excavations are generally surrounded with dense buildings, and their working space is very narrow, especially when they are close to the foundations of adjacent buildings or structures. So it is important to forecast and control the deformation of deep excavation and its surroundings.There are four theories to analyze ground settlement around deep excavation: experience estimation method, the theory of the loss of the layer, safety factor of resistant heave method and time and space effect method. Base on the above method, this paper propose a new model of predict of ground settlement. Under condition of cantilever retaining structure and internal-shoring supporting structure, is different. Those classical methods all use function model to describe and forecast the deformation. Also the new model can forecast two distribution types of ground settlement by use different parameters. The new model of forecasting take something into consideration which including soil property, the relationship between retaining structure displacement and ground settlement, the relationship between the maximum settlement and safety factor of resistant heave, the place where the maximum settlement appear, and so on. Base on large numbers of practical work, the experiential relationship between the maximum retaining structure displacement and the maximum ground settlement and other factors, author ascertain the model parameters. Its validity was confirmed through comparison with the test results. Finally, the conclusions that are valuable for forecast of ground settlement and protect of environment and construction of deep foundation engineering.