Triaxial Test Study on Relations Between Pore Pressure and Strain in Aerated Fine-Grained Soil
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摘要: 通过沸石的微孔吸附特性制作重塑细粒含气土,开展一系列不同有效围压的不排水剪切试验,研究含气量对重塑细粒土孔压变化规律和应变等值线的影响。在轴向应变达到5%之前,饱和土中孔压发展速度大于含气土的孔压;在轴向应变达到5%之后,含气土的孔压大于饱和土的孔压。在达到相同的应变下,含气土中产生的孔压更大,相应抗剪强度更小。在不同的含气量下,临界状态线的斜率M值是一个常数,M=1.25。不同含气量的土体在不同围压下有效应力路径上的应变等值线可视作直线,且其斜率随着应变的增加逐渐增大,最终与临界状态线重合。Abstract: A series of undrained shear tests with different effective confining pressures were conducted to study the effect of the gas content on pore pressure variation and strain isolines of remolded fine aerated soil based on the microporous adsorption properties of zeolite. Before the axial strain reached 5%, the pore pressure of saturated soil developed faster than that of aerated fine-grained soil, while the axial strain exceeded 5%, the pore pressure of aerated soil developed faster than that of saturated soil. In the same strain, the pore pressure in aerated soil was larger and the corresponding shear strength was smaller. In different contents of gas, the slope of the critical state line was a constant, it was 1.25. The strain isolines along the effective stress paths of soil with different contents of gas under different confining pressures could be regarded as straight lines, and their slopes increased gradually with the increase of strains and finally coincided with the critical state lines.
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Key words:
- aerated soil /
- fine-grained soil /
- air content /
- pore pressure /
- stress path
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[1] FLEISCHER P, ORSI T, RICHARDSON M, et al. Distribution of free gas in marine sediments: a global overview[J]. Geo-Marine Letters, 2001, 21(2):103-122. [2] LI Y L,LIN C M.Exploration methods for late Quaternary shallow biogenic gas reservoirs in the Hangzhou Bay area, eastern China[J]. AAPG Bulletin, 2010, 94(11):1741-1759. [3] 韩珠峰, 王勇, 孙富学,等. 一种海底含气软土的室内模拟制样方法[J]. 实验室研究与探索, 2021, 40(1):16-21. [4] HONG Y, WANG L, YANG B, et al. Stress-dilatancy behaviour of bubbled fine-grained sediments[J/OL]. Engineering Geology, 2019[2021-12-24]. https://doi.org/10.1016/j.enggeo.2019.105196. [5] HONG Y, WANG L, NG C, et al. Effect of Initial Pore Pressure on Undrained Shear Behaviour of Fine-grained Gassy Soil[J/OL]. Canadian Geotechnical Journal, 2017[2021-12-24]. https://doi.org/10.1139/cgj-2017-0015. [6] 刘文卓. 常剪应力路径下含气砂土的三轴试验研究[D]. 青岛:青岛理工大学. [7] 孔亮, 刘文卓, 袁庆盟,等. 常剪应力路径下含气砂土的三轴试验[J/OL]. 岩土力学, 2019(9)[2021-12-24]. https://10.16285/j.rsm.2018.1863. [8] 韩珠峰. 波浪作用下砂质含气海床的动力响应特性研究[D]. 桂林:桂林理工大学,2020. [9] WHEELER S J, SHAM W K, THOMAS S D. Gas pressure in unsaturated offshore soils[J/OL]. Canadian Geotechnical Journal, 1990[2021-12-24]. https://doi.org/10.1139/t90-008. [10] GARZIGLIA S. Mechanical behaviour of gas-charged fine sediments: model formulation and calibration[J]. Géotechnique, 2014, 64(11):851-864.
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