Reasonable Selection Of Supporting Scheme For Deep Foundation Pit In Wenling Based On Value Engineering

With the increasing of Wenling’s economic strength, more and more high-rise buildings continue to emerge in Wenling. To improve the capacity rate of the land, the foundations of high-rise buildings are made deeper and deeper. The patterns of foundation pit support have some different selections, so it’s becoming much more difficult for designers to choose their schemes. Accident statistics of the Ministry of Construction in recent years show that65%of the collapse accidents are caused by foundation pit and hand-dug pile construction in the process of construction. Thus it can be seen that foundation pit support is a high risk in the construction industry. Therefore, how to choose a rational scheme and prevent the occurrence of foundation pit collapse accident is the direction of research for this topic. I have collected over10foundation pit supporting schemes in recent years in Wenling. I research into their support structure, design for resisting the water beside the foundation pit, worksite’s monitoring data of foundation pit, combining the influences of foundation peculiarities in different areas of Wenling. For the same project, the author of this thesis compares the work principle, characteristics and scope of application of row pile retaining wall, depth cement mix pile gravity type retaining wall, composite soil nailing wall, portal bracing and etc. and then elaborates the basic principle of value engineering and uses it to optimize the model of foundation pit supporting scheme. I achieved the function index system of foundation pit supporting scheme by using the functional analysis system technology (FAST), meanwhile, I confirmed the weight of each function evaluation index by hierarchy analysis theory and0to4scoring method. Then I calculated the function indexes by organizing experts to mark each alternative scheme to get the scores of function. At last, I picked out the optimal scheme by estimating the cost of each sub-item project which leads to cost index and value coefficient among several alternatives.