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| A modulus reduction method for calculating loess unloading collapse |
| JIN Xin1，WANG Tiehang2，ZHANG Yu1，3，ZHANG Meng1 |
| (1. School of Civil and Architecture Engineering，Xi¢an Technological University，Xi¢an，Shaanxi 710021，China；2. College of Civil Engineering，Xi¢an University of Architecture and Technology，Xi¢an，Shaanxi 710055，China；3. Shaanxi Key Laboratory of Loess Mechanics and Engineering，Xi¢an University of Technology，Xi¢an，Shaanxi 710048，China) |
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Abstract Loess unloading collapse widely exists in test pits and the loess between piles. On the premise of ensuring the safety of loess engineering，it is important to boost the economy and rationality of engineering projects. To achieve efficient calculation of loess unloading collapse，the inverse analysis of loess collapse tests under constant loads is carried out，and the relationship between the collapse coefficient and the modulus reduction coefficient under constant loads is established according to that the deformation modulus of loess decreases after immersion. Furthermore，the inverse analysis of loess unloading collapse tests is performed，and the relationship between the unloading collapse coefficient and the modulus reduction coefficient is proposed. A modulus reduction method for calculating the loess unloading collapse is obtained with the help of the relationship between the collapse coefficient and the unloading collapse coefficient，and verified through evaluating the relationship between the unloading collapse coefficient and the modulus reduction coefficient by setting the unloading amount equal to zero to simulate the constant loading case. The research results provide an efficient way for analyzing loess unloading collapse and improve the collapse evaluation system.
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2021, Vol. 40 
