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| STRUCTURAL DAMAGE EVOLUTION AND CONSTITUTIVE RELATION OF LOESS UNDER COUPLING OF STRESS AND MOISTURE |
| LUO Aizhong1，2，SHAO Shengjun1 |
(1. Institute of Geotechnical Engineering，Xi'an University of Technology，Xi'an，Shaanxi 710048，China；
2. School of Architecture Engineering，Bijie University，Bijie，Guizhou 551700，China) |
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Abstract In order to study the deformation of destructured loess induced by structural damage under coupling of stress and moisture，the macromechanics reflection of structured loess is analyzed，which is induced by structural damage development，by analyzing the deformation of structured loess under compression tests and triaxial tests. The analysis result shows that water content increasing，consolidation pressures increasing，and shearing would cause structural damage of loess. With the water content increasing，structural damage of loess is more prominent by compression and shearing. When consolidation pressures are much larger，structural damage of intact loess by compression and shearing is significant，and the secondary structure and shearing-compression are increasing. Based on structural parameter proposed by comparing with the stress ratios of intact loess and saturated remolded loess during triaxial experiments，and utilizing the stress ratio damage equation and strain damage equation，the structural damage evolution equation is proposed by regarding structural damage loess as complex materials composed of intact loess and destructured loess. Based on the intact loess following Hooke?s law and normal consolidation loess following modified Cambridge model，the elastoplastic damage constitutive equation is proposed by regarding deformation of destructured loess as elastic deformation of intact loess and elastoplastic deformation of normal consolidation loess. Meanwhile，the rationality of constitutive relationship is tested and verified by comparing and analyzing test curves under different moistures and theoretical curves described by the elastoplastic constitutive model proposed in this paper.
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Received: 31 October 2011
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2012, Vol. 31 
