The Effectiveness Analysis Of Deep Excavation To Adjacent Underground Utilities

Underground pipelines is an important life line in cities. Ground settlement and soil movement induced by deep foundation excavation in metropolises will have negative influence on surrounding buried pipelines. Applying the traditional design theory and routine construction technology, there is inevitable difficulty about protecting the buried pipeline. Many scholars, engineers and technicians have already worked a lot in the displacement-controlling design of deep foundation excavation in recent years, however, there are still many problems in finding the displacement laws in which bracing structure, soil and buried pipelines are taken into account.Combining the Shanghai Shibo Power Station Project, the thesis analyzes and researches the effect of deep excavation to adjacent underground utilities and pipelines' safety problem. Using finite differential geotechnical software FLAC^3D, considering the reciprocity of foundation pit, ground soil and adjacent pipelines, the thesis establishes relevant analysis model The influence of excavation to adjacent pipelines in deep foundation excavation is simulated. The simulated elements include stepped excavation, foundation pit dimension, different pipeline diameters and distance from excavation. Finally, the study achieve distortion discipline of pipelines effected by before elements.Meanwhile, the thesis summarizes the method to assess the pipelines safety conditions. When knowing the pipeline material, lateral and vertical displacement of pipe, rotation and stress can be calculated, through that we can assess the pipeline safety condition. The thesis also put forward the method to assess distortion of pipelines before excavation, that can be used to make primary assessment.In the finality, the problems requiring further studies are discussed.