Catastrophe Theory Model Applied In Microstructural Un-stability Of Collapsible Loess

Loess is widely distributed in northwest China, north China, as the foundation forall types of building projects has a long history. Collapsible loess has high strength andlow compression in natural low humidity. Once the flooding will occur strengthsignificant dips and deformation substantial increased greatly.Buildings built in the collapsible loess foundation because the foundation wassoaked in water during use or after the completion of construction which led to thefrequent occurrence of building subsidence or damage.With the development ofcollapsible loess construction projects, in-depth study of collapsible loess collapsiblenature of the correct evaluation of collapsibility degree of rational control of loesscollapse deformations, has a very important significance to the construction of thewestern.This article is from the stability point of view, it analyzes a variety of collapsiblemechanism of loess collapsibility, introduces the main ideas of catastrophe theory andthe different mutation model, with the mutation theory of mathematical models andcalculation methods used in collapsible loess micro-structural instability of themutation process, and the process is simulated calculation, then the simulation isrevealed the deformation mechanism and the collapsible rule of collapsible loess, fromthe perspective of catastrophe theory.In this paper, a simple and intuitive overhead gap model is established, and a clearmodel assumption is given. Then the instability criterion of collapsible loessmicrostructure model can be calculated, respectively through the fold catastrophemodel and the cusp catastrophe model. So the expression of the clear criteria is given.It can be proved that the pore of collapsible loess microstructure model wouldcollapsed, when the stress to meet the bifurcation point set equation of the catastrophemodel, that is, the loess collapsibility.Because the he model control variable with thestiffness coefficient k (the water content of function) changed, therefore the calculationmethod again proved the loess soaking wet in the loess of the collapsible importantfactors.