温度影响粉质黏土固结和强度特性的试验研究  

Experimental Study of Temperature Effects on Consolidation and Strength Properties of Silty Clay

作　　者：陆嘉楠 徐洁[1,2] 陈永辉[1,2] 

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,江苏南京210098 [2]河海大学岩土工程科学研究所,江苏南京210098

出　　处：《防灾减灾工程学报》2017年第4期598-603,共6页Journal of Disaster Prevention and Mitigation Engineering

摘　　要：随着能源岩土工程的发展,温度对土体固结和强度特性的作用变得越来越重要。采用温控三轴仪,通过等温增压固结试验、等压升温固结试验和温控三轴剪切试验,研究温度对饱和粉质黏土固结和强度特性的影响。结果表明,温度越高,土体固结速率越快,固结体应变越大。不同温度下试样的正常固结线几乎平行。同一围压作用下,温度越高,孔隙比越低。热应力造成的固结体应变随温度升高呈线性增长。剪切过程中,轴向应变较小时,同样偏应力作用下,温度越高,轴向应变越小;而轴向应变较大时,趋势相反。试样破坏偏应力随温度升高而线性减小,且围压越大,温度效应越明显。有效粘聚力c′随温度升高而减小,而有效内摩擦角φ′则不受温度的影响。With the development of geo-energy engineering, temperature effects on consolidation and strength properties of soil become more and more important. Temperature-controlled triaxial apparatus are adopted to study the temperature effects on consolidation and strength properties of a silty clay by consolidation tests with increasing confining pressure under constant temperature, consolidation tests with increasing temperature under constant confining pressure and tempera- ture-controlled triaxial compression tests. Test results show that consolidation rate is faster and consolidation volumetric strain is larger at a higher temperature. The normal consolidation lines under different temperatures are almost parallel to each other. Under the same confining pres- sure, void ratio is lower at a higher temperature. Consolidation volumetric strain induced by thermal stress increases linearly with increasing temperature. During shearing, the axial strain is higher at a higher temperature for the same deviator stress at low axial strains, while the trend is opposite at high axial strains. Deviator stress at failure decreases linearly with increasing temper- ature. The temperature effects are more significant at a higher confining pressure. Effective co- hesion c＇ decreases with increasing temperature, while effective friction angle is not affected by temperature.

关 键 词：温度 固结 抗剪强度 温控三轴试验 

分 类 号：TU411[建筑科学—岩土工程]