Deep foundation pit is a complicated geotechnical engineering which is related to lots of subjects.At present, there are many supporting methods for deep foundation pit. Because the supporting form of composite soil-nailed wall is very flexible and offset the deficiency that general soil-nail support has,it is used more and more comprehensively in practical project. Moreover, most of the deep foundation pit are temporary projects and their duration are very short. As a result people are easy to have fluke m...