岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2014年
3期
637-640
,共4页
马芹永%张经双%陈文峰%袁璞
馬芹永%張經雙%陳文峰%袁璞
마근영%장경쌍%진문봉%원박
人工冻土%冻结黏土%分离式Hopkinson压杆(SHPB)%试验%围压状态%应变率效应%温度效应
人工凍土%凍結黏土%分離式Hopkinson壓桿(SHPB)%試驗%圍壓狀態%應變率效應%溫度效應
인공동토%동결점토%분리식Hopkinson압간(SHPB)%시험%위압상태%응변솔효응%온도효응
artificial frozen soil%frozen clay%split Hopkinson pressure bar (SHPB)%test%confining pressure%strain rate effect%temperature effect
利用分离式Hopkinson压杆(SHPB),以铝质套筒作为围压装置,分别研究温度为-8、-12、-16℃在不同应变率下的人工冻结黏土围压状态变形特征和轴向动态应力-应变关系。研究结果表明:在围压状态下,冻土呈黏塑性破坏特征;当人工冻结黏土温度为-16℃、平均应变率分别为410、457、525、650、827 s-1时,其最大应力分别为10.76、12.18、14.27、20.24、23.34 MPa,最大应变分别为0.0817、0.0972、0.1050、0.1310和0.1660,表现出较强应变率效应;-12℃和-16℃时在应变率为457 s-1下的最大应力分别为8.28 MPa和12.18 MPa;当应变率相同时,温度越低,最大应力越大,冻结黏土表现出较强的温度相关性。人工冻土的动力学特性为冻土开挖方法的研究提供依据。
利用分離式Hopkinson壓桿(SHPB),以鋁質套筒作為圍壓裝置,分彆研究溫度為-8、-12、-16℃在不同應變率下的人工凍結黏土圍壓狀態變形特徵和軸嚮動態應力-應變關繫。研究結果錶明:在圍壓狀態下,凍土呈黏塑性破壞特徵;噹人工凍結黏土溫度為-16℃、平均應變率分彆為410、457、525、650、827 s-1時,其最大應力分彆為10.76、12.18、14.27、20.24、23.34 MPa,最大應變分彆為0.0817、0.0972、0.1050、0.1310和0.1660,錶現齣較彊應變率效應;-12℃和-16℃時在應變率為457 s-1下的最大應力分彆為8.28 MPa和12.18 MPa;噹應變率相同時,溫度越低,最大應力越大,凍結黏土錶現齣較彊的溫度相關性。人工凍土的動力學特性為凍土開挖方法的研究提供依據。
이용분리식Hopkinson압간(SHPB),이려질투통작위위압장치,분별연구온도위-8、-12、-16℃재불동응변솔하적인공동결점토위압상태변형특정화축향동태응력-응변관계。연구결과표명:재위압상태하,동토정점소성파배특정;당인공동결점토온도위-16℃、평균응변솔분별위410、457、525、650、827 s-1시,기최대응력분별위10.76、12.18、14.27、20.24、23.34 MPa,최대응변분별위0.0817、0.0972、0.1050、0.1310화0.1660,표현출교강응변솔효응;-12℃화-16℃시재응변솔위457 s-1하적최대응력분별위8.28 MPa화12.18 MPa;당응변솔상동시,온도월저,최대응력월대,동결점토표현출교강적온도상관성。인공동토적동역학특성위동토개알방법적연구제공의거。
Split Hopkinson pressure bar (SHPB) was adopted to study the deformation behaviors and axial dynamic stress-strain relationship of artificial frozen clay in confining pressure state. Three kinds of artificial frozen clay with frozen temperatures of-8℃,-12℃and-16℃were investigated in SHPB test. And aluminum sleeve was chosen as confining pressure device. The results show that viscoplasticity failure is presented when artificial frozen soil in confining pressure state under high strain rate. When average strain rates are 410 s-1, 457 s-1, 525 s-1, 650 s-1 and 827 s-1, the maximum stresses of artificial frozen soil at-16℃are 10.76 MPa, 12.18 MPa, 14.27 MPa, 20.24 MPa and 23.34 MPa respectively;and the maximum strains of artificial frozen soil at-16℃are 0.081 7, 0.097 2, 0.105 0, 0.131 0 and 0.166 0 respectively. Besides, when average strain rate is 457 s-1, the maximum stress of artificial frozen soil at-12℃is 8.28 MPa;and the maximum stress of artificial frozen soil at-16℃is 12.18 MPa. When the strain rate is the same, the lower the frozen temperature, the larger the maximum stress of artificial frozen soil. Strong temperature correlation could be observed from artificial frozen soil in high strain rate. Research on dynamic mechanical behaviors of artificial frozen clay will provide some supports for frozen soil excavation.