不同幅值温度荷载下一种饱和红黏土的固结效应  

Consolidation effects of a saturated red clay subjected to temperature loading with different amplitudes

作　　者：白冰[1] 张鹏远[1] 贾丁云[1] 蒋思晨[1] 

机构地区：[1]北京交通大学土木建筑工程学院,北京100044

出　　处：《岩土工程学报》2013年第11期1972-1978,共7页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(51279002);中央高校基本科研业务费专项基金项目(2012YJS086)

摘　　要：通过室内试验,研究一种饱和红黏土在不同升温幅值温度荷载作用下的固结效应。亦即,首先将试样在初始温度20℃和一定围压下(σ3=50,100,150,200 kPa)进行固结。然后,在不排水条件下将试样温度由20℃上升至40℃(或50℃,60℃,70℃,80℃),再让试样在该温度荷载下进行等温排水固结。试验表明,温度荷载引起的孔隙水压力最大值随升温幅值的增大而增大,达到同一温度设定值后的孔隙水压力与围压比随围压的增大而相应减小,而孔隙水压力值则增大。在温度荷载作用下,固结体应变随温度幅值的增大而增大,而随围压的增大有减小的趋势。在相同幅值温度荷载和相同围压作用下,红黏土的孔隙水压力增长速率及最大值要明显大于一种低塑性的粉质黏土,而其固结体应变却要小些。The consolidation effects of a saturated red clay subjected to temperature loading with different amplitudes are studied. The specimens subjected to different confining pressures （i.e., σ＇3=50, 100, 150, 200 kPa） are firstly consolidated at a primary temperature of 20℃ and then are heated to different higher temperatures （i.e., 40℃, 50℃, 60℃, 70℃and 80℃） under undrained and drained conditions at the desired temperature. The test results show that the peaks of the pore pressure induced by heating increase with the increase of the amplitudes of the thermal loading, and the ratios of the pore pressure to the confining pressure decrease with the increase of the confining pressure when the temperature of specimens reaches the same desired value, while the pore pressure increases actually. Under drained conditions, the volumetric strain increases with the increase of the amplitudes of thermal loading and decreases as the confining pressure increases. Besides, in the case of the same thermal loading and confining pressures, the thermal consolidation volumetric strains of the red clays are commonly greater than those of a saturated silty clay with low plasticity index.

关 键 词：红黏土 矿物成分 温度幅值 孔隙水压力 塑性指数 

分 类 号：TU411[建筑科学—岩土工程]