Numerical Analysis On Double-row Piles & Development Of The Software For The Design Of Pit Retaining Structures

In recent years, with rapid development of urban construction, the need for underground space is increasing. As a result, deep excavation projects are more and more widespread. In the meantime, the design of pit retaining structures bears different characters concerning different regions and the software in this area is numerous and complicated; so a program aiming at the new-style retaining structure of double-row piles is developed assimilating the latest scientific research results.In this self-coded program, the mechanism of distortion and internal forces is well analyzed with different calculating models with respect to different structures. The rigid coefficient of the spring used to simulated friction resistance between piles and soil is deduced, and the distributing coefficient judging the rationality of the distribution of the moment of the piles is put forward in this passage. The effect on double-row piles caused by the factors such as joint model between the top of pile and linking beam, space between front and back piles and so on is discussed in this thesis. What's more, modification is made based on normal elastic ground resistance method and a rigid matrix for elastic ground beam element is detruded. The double-row piles with both inclined and horizontal bolsters are also analyzed in consideration of staged excavation.Finally, some useful results have been obtained through analysis of different examples, and the results can provide a theoretical base for engineering practice; Furthermore, this thesis has made full analysis on a practical engineering example of the city of Tianjin.