Loess Collapsibility Analysis

Loess uses all kinds of construction work for long history as grounds. And the coUapsibility of loess has been a typical project geological question of the loess area all the time .The coUapsibility of loess often causes enormous danger to engineering construction activity of distributing area, extremely damaging in architecture to the project. It is very important that we clarify the origin of loess coUapsibility in order to prevent and reduce the coUapsibility of loess. We need to carry on further analysis and research to the coUapsibility of loess. On the basis of a large amount of work that forefathers have done, the scientific research projects of Ministry of Communications that this text " surveys the coUapsibility dark cave technical research of loess " through participating in the western traffic, had carried on the coUapsibility quantitative analysis of loess to four areas of LongXi, LongDong, ShanBei, GuanZhong and studied its regularity.First of all, the pertinence samples were excavated which added up to more than 150 groups altogether in four region. They were carried on routine test, grain size analysis, coUapsibility, the test of the second coUapsibility in laboratory and drawn the law that the loess nature in this area changes and the relation among coUapsibility coefficient and mechanics index of physics. Meanwhile, this paper studied their impact on loess coUapsibility by scanning electric mirror to show microstructure, matrix mineral and cementation element and study their relations.Secondly, the paper carried on loess mineral diffraction half quantitative analysis, X of composition, tested and analyzed soluble salt content and composition and the content of unsoluble salt (CaCO₃), and studied their impact on the coUapsibility of loess with representative soil kind separately.Finally, there are a lot of factors influencing coUapsibility of loess. But in this text, each factor was analyzed synthetically and the main influence factor and secondary influence factor were distinguished. Adopting the combined way of qualitative and quantitative analysis synthetically, the independent factors which influences to coUapsibility loess significantly were showed by the way of regressionanalyze and fuzzy mathematics. The relations between collapsibility and them were set up, the significant factor was made sure, and the reliability was analyzed. This model directed a way for the unsatured loess collapsible constitution study, and also set up a basis for loess collapsibility assessment with some easy measured indices.