Experimental And Application Research On The Mechanical Properties Of Residual And Diluvia Soil In Yuelu Mountain

Residual soil is the remaining part of rocks experiencing weathering, whilediluvia soil is the migrating part that locates on the lower position or the foot of theslope. When constructing high level roads in the southern China, a number of highand abrupt slopes will come up due to the distribution of large area of residual anddiluvia soil covering. Numerous engineering practices indicate that water plays themost crucial role in the occurrence of landslide for slopes therein, so it deservessignificance in both theoretical and practical aspects to investigate the influence ofwater on the mechanical properties of residual and diluvia soil. This work devotedinto the test study on the strength variation of residual and diluvia soil in YueluMountain against increasing times of dry-wet cycle and the duration of soaking.Firstly, it started from the tests on the genetic styles, classification and thephysical and mechanical index of the object soil.What followed is to the design of the triaxial shearing test in laboratory and togive a rational analysis and explanation to the phenomena in the process of testing.The shearing strength test of saturated residual and diluvia soil under various times ofdry-wet cycle was carried out by using the advanced GDS triaxial system. The resultsillustrates that it is a nonlinear relationship between the undrained strength and thenumber of dry-wet cycles. An exponential function was used to fit the relationshipand an analytical formula of the above two quantities for the residual and diluvia soilin Yuelu Mountain was given. On this basis, the stress and strain constitute relation ofthis soil on the application of dry-wet cycle was established by applying BP neuralnetwork, and was used to analyze its strength characteristic.In an analogical procedure, the nonlinear relationship of the undrained strengthand the duration of soaking was observed and fitted by also the exponential function,along with a derived closed formula. Adaptive Neuro-Fuzzy Inference System(ANFIS) was employed to construct the stress-strain model and explore the strengthproperty of the objective soil.Finally, the fruit of this work was applied to an slope enhancement engineeringnearby Qixiang South Road of Changsha. The slope stability assessment was given ondifferent dry-wet cycles and changing duration of soaking, the variation of Factor OfSafety (FOS) was obtained by changing the two conditions.