Experimental study on strain accumulation characteristics of saturated remolded loess under pure rotation of the principal stress axis

Frontiers in Ecology and Evolution

Ecology and Evolution

Zuliang Zhong¹  Dongyu Zhang²  Fuxing Ni²  Bo Wu²  Bin Chen²  Sui Wang³ 

[1] College of Civil Engineering, Chongqing University, Chongqing, China;Key Laboratory of New Technology for Construction of Cities in Mountain Area (Chongqing University), Ministry of Education, Chongqing, China;School of Civil and Transportation Engineering, Ningbo University of Technology, Ningbo, China;School of Civil and Transportation Engineering, Ningbo University of Technology, Ningbo, China;College of Civil Engineering, Chongqing University, Chongqing, China;Key Laboratory of New Technology for Construction of Cities in Mountain Area (Chongqing University), Ministry of Education, Chongqing, China;

关键词: saturated loess;    principal stress axis rotation;    cyclic degradation;    strain accumulation;    pore pressure accumulation;   

DOI  :  10.3389/fevo.2023.1275648

 received in 2023-08-10, accepted in 2023-09-07,  发布年份 2023

来源: Frontiers

【 摘 要 】

The study conducted a pure rotation test of 720° for saturated remolded Q2 loess under principal stress axis (PSA) rotation when deviatoric stress and the intermediate principal stress ratio are different, also paying attention to examining the changes of strain accumulation and pore pressure of such loess. According to the test, as the PSA rotates continuously, the pore water pressure exhibited by saturated remolded loess presents a normal cyclic accumulation elevation, and under the same deviatoric stress conditions, the pore water pressure accumulation trend of different principal stress ratios is the same; however, the magnitude is different. The increment of pore water pressure becomes smaller as the number of cycles increases. When the deviatoric stress level is low, the material hardening is in a cyclic stable state, the strain component remains stable with the continuous rotation of the PSA, and the strain path area is reduced, together with a stable final size. In case of higher deviatoric stress, the material strength cycle becomes weaker and the strain component accumulates slowly as the PSA (the spiral line of the strain path) continuously rotates in the γzθ−(ϵz−ϵθ) plane, and gradually expands until failure. The increased intermediate principal stress is accompanied by accelerated strain development speed and advanced failure.

【 授权许可】

Unknown   
Copyright © 2023 Wang, Zhong, Chen, Wu, Zhang and Ni