通过真三轴测试验证一种新的应力路径方法
Zhigang Ma1,2, Xuefeng Li3,4, Longlong Lv1
1School of Civil and Hydraulic Engineering, Ningxia University, Yinchuan, 750021, China.
Scientific reports
|March 14, 2024
概括
使用伪三轴装置的新方法在土壤测试中成功复制了真三轴应力路径. 这种方法简化了3D土壤分析,降低了成本,同时保持了高精度.
科学领域:
- 地质技术工程 地质技术工程
- 土壤力学 土壤力学
- 实验方法 实验方法
背景情况:
- 真三轴装置允许精确控制应力路径.
- 伪三轴装置更常见,但在应力路径控制方面有限.
- 验证新的方法来扩大伪三轴装置的能力至关重要.
研究的目的:
- 用伪三轴装置验证一种用于实现真三轴应力路径的新方法.
- 用伪三轴和真三轴装置进行的测试之间的差异量化.
- 评估新型土壤测试方法的可行性和合理性.
主要方法:
- 根据相同的方案,使用伪三轴和真三轴装置进行了排水和未排水的测试.
- 控制了伪三轴装置的负载比,以实现真三轴应力路径.
- 应力-应变关系 (q-ε1, η-εs) 和临界状态线的量化差异.
主要成果:
- 这种新方法有效地实现了真三轴应力路径.
- 从两种装置的q-ε1和η-εs关系中观察到很高的相似性,随着b值的增加而略有下降.
- 关键状态线的斜率显示出良好的一致性,较高b值的偏差小 (<10%).
- 通过这两种方法测量的峰值强度接近莫尔-库伦标准.
结论:
- 这种新的方法是可行和合理的,可以通过伪三轴装置实现真三轴应力路径.
- 这种方法显著扩大了伪三轴装置的测试范围.
- 该方法简化了3D土壤测试过程,并降低了总体测试成本.
相关概念视频
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