为研究固化淤泥土经过冻融循环后的力学性质变化及其劣化机理,通过无侧限抗压强度试验、直剪试验、固结试验等土力学试验对其形变特征、内摩擦角、黏聚力以及压缩特性的变化进行分析。结果表明:固化淤泥土随着冻融循环次数的增加,其无侧限抗压强度、内摩擦角、黏聚力以及压缩屈服压力等重要力学指标均出现减小的现象;6次冻融循环后,固化淤泥土达到承受极限,在此之后试样的各项力学指标将发生突变,破坏类型变为脆性破坏。研究成果可为固化淤泥土冻融循环劣化防治措施的制定提供科学的思路。
Abstract
To study the mechanical properties and degradation mechanism of solidified silt undergone cyclic freezing and thawing,we analyzed the changes in deformation feature, internal friction angle, cohesive force, and compression features of solidified silt via unconfined compressive strength test, direct shear test and consolidation test. Results demonstrated that with the proceeding of cyclic freezing and thawing, the unconfined compressive strength, internal friction angle, cohesion, and compression yield pressure of solidified silt all degraded. After six cycles, the mechanical indexes of solidified silt reached a critical status and changed abruptly towards brittle failure. The research finding could offer scientific idea for preventing and controlling the degradation of solidified silt.
关键词
固化淤泥土 /
冻融循环 /
形变特征 /
无侧限抗压强度 /
抗剪强度
Key words
solidified silt /
freeze-thaw cycle /
deformation feature /
unconfined compressive strength /
shear strength
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基金
国家自然科学基金项目(51709154);
湖北省自然科学基金项目(2016CFB237);
三峡大学硕士学位论文培优基金(2018SSPY026)
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