Mechanical Properties of Improved Luoyang Expansive Soil under Dry-wet Cycle
MA Jianjun
ZHANG Yugang
WANG Chaosheng
CHENG Shukai
ZHAO Mingchong
Abstract：To investigate the improvement effect of cement on Luoyang expansive soil,and to reveal the strength degradation laws and crack evolution characteristics under wet-dry cycles,indoor experiments were conducted on Luoyang expansive soil with different cement ratios under dry-wet cycles.The grey relational degree and random forest methods were introduced to establish a macro-meso analysis model for expansive soil.The results indicate that the incorporation of cement alters the composition of Luoyang expansive soil and significantly reduces the free swelling rate.When the cement content reaches 6％(mass fraction),the expansive soil is transformed into non-expansive soil.With the increase in cement content,the compactness,unconfined compressive strength,and elastic modulus of the expansive soil first increase and then decrease,and the failure mode of the specimen transitions from plastic to brittle failure.As the number of dry-wet cycles increases,the strength and elastic modulus of the improved expansive soil exhibit a nonlinear decreasing trend and eventually stabilize.The optimal cement content is determined to be 6％.Analysis reveals that crack indicators are significantly correlated with compressive strength,with the mean crack width showing the strongest correlation.A random forest model was established for regression analysis,and the model demonstrated high accuracy and excellent performance in prediction.
Keywords：Luoyang expansive soildry-wet cycleunconfined compression testfracture indexrandom forest model
Publication Date：2025-10-25
Online Publishing Date：2025-11-17(First online date of this platform, not the publication date of the document)
Pages：10( 51-60 )