| 摘要: |
| 为实现在实验室条件下研究深海沉积物原位应力状态和温度条件下的力学特性, 作者自主研制一套可精密量测体变的海底沉积物温压环境三轴试验系统。基于土工应力路径三轴试验系统, 通过采用内外双重水浴循环设计, 实现对试样的均匀精确控温; 通过采用双压力室内外压力平衡设计, 实现深海高压应力加载和控温条件下试样体变的精确量测。对试验系统进行控温测试和三轴试验重复性测试, 测试结果显示试验系统可长时间稳定精确控温, 同时实现控温条件下的样品体变量测。采用Ottawa砂重塑制备饱和砂质沉积物试样, 开展了4个温度条件下的三轴排水剪切试验, 结果表明: 5~40 ℃范围内, 随温度降低砂土的抗剪强度减小, 剪缩性减弱, 初步检验了所研制试验系统的可靠性, 该系统可为研究深海沉积物的力学特性提供技术装备支撑。 |
| 关键词: 砂质沉积物 三轴剪切 温压环境 控温条件 体变量测 |
| DOI：10.11759/hykx20241205002 |
| 分类号:TU415 |
| 基金项目:国家自然科学基金重大仪器专项(52127815);国家自然科学基金资助项目(52178372) |
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| Development and preliminary application of a triaxial test system for the temperature and pressure environment of submarine sediments |
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MA Tengfei1,2, WANG Yong2, JIA Pengfei1, XU Guofang2, CHEN Jiakai2
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1.Department of Geology/State Key Laboratory of Continental Dynamics, Northwest University, Xi'an 710069, China;2.State Key Laboratory of Geomechanics and Geotechnical Engineering Safety, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China
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| Abstract: |
| To investigate the mechanical properties of deep-sea sediments under in situ stress and temperature conditions in the laboratory, a self-developed underwater sediment triaxial testing system with precise volumetric measurement capabilities was created. Building upon a geotechnical stress path triaxial testing system, the developed system incorporates a dual water bath circulation design to achieve uniform and precise temperature control of sediment specimens and a dual pressure chamber design to enable high-pressure stress loading and precise volumetric measurements under deep-sea pressure and temperature conditions. The system was tested for temperature control and triaxial test repeatability, and the results demonstrated stable and precise temperature control over extended durations and reliable volumetric measurements under temperature-controlled conditions. Ottawa sand was used to prepare saturated sandy sediment specimens, and triaxial shear tests were conducted under four temperature conditions. The results indicated that within the range of 5-40℃, decreasing the temperature reduces the shear strength and deteriorates the shrinkage characteristics of the sand. The above tests preliminarily verified the reliability of the developed testing system, providing technical support for studying the mechanical properties of deep-sea sediments. |
| Key words: sandy sediments triaxial shear temperature and pressure environment temperature control conditions volumetric measurement |
