摘要
采用振动台物理模拟试验方法,输入振幅逐渐增大的水平向正弦波加速度,对比分析了抗滑桩加固前后二元顺层边坡的动力响应特征,采用MIDAS/GTS软件对模型试验得出的结果进行数值分析,结果表明:(1)二元结构顺层边坡,破坏时与均质边坡的相似之处为:受高程放大效应和垂直放大效应影响,破坏的初始首先在边坡的中上部产生拉裂缝,放大系数最大值出现的位置往往就是边坡初始破坏的位置。与均质边坡不同的是:最初产生的拉裂缝不一定会发展成为控制裂缝,拉裂缝产生之后并不会在土体内部产生控制性剪切裂缝,进而产生滑裂面,而是会沿二元结构面产生滑动破坏。(2)抗滑桩在水平地震动作用下倾倒破坏的轴心并不一定是在抗滑桩外侧与土体交界面处,本例中位于滑面下1 m处。(3)锚杆与抗滑桩联合支护时锚杆可有效减小抗滑桩的弯矩,提高抗滑桩在静力和动力荷载下抵抗破坏的能力。研究结果对二元顺层边坡的抗震设计与分析有一定参考价值。
Physical simulation experiments were adopted to study the dynamic responses of the model slopes. The horizontal acceleration of sine wave whose amplitude increased gradually with time, was input into the slope model. Then by using MIDAS/GTS software, the results of the model tests were verified, which indicated that the failure pattern of bedding slope with dual structure was similar to the homogenous slope and affected by the elevation and vertical magnification, both the tension fissure and maximum coefficient of magnification occurred in the upper part of the slope. But the tension fissure in the bedding slope with dual structure might not be the controlling cracks and resulted in slide face, otherwise the failure occurred along the interface between soil and rock. The anti-slide pile overturned under horizontal ground motion with the axis below the slide surface at the depth of 1 meter, but not the intersection of outer flank of anti-slide pile and soil. The combined support of anchored bolt and anti-slide pile can effectively reduce the bending moment in anti-slide pile, and increase the resistance of anti-slide pile both understatic and dynamic load. The research results can be a good reference to anti-seismic design of bedding slope with dual structure.
出处
《地震工程与工程振动》
CSCD
北大核心
2014年第6期248-255,共8页
Earthquake Engineering and Engineering Dynamics
基金
国家自然科学基金(41262010)
甘肃省科技计划资助(1310RJZA041)
甘肃省基础研究创新群体资助(145RJIA332)
长江学者和创新团队发展计划(IRT1139)
关键词
抗滑桩
二元结构顺层边坡
模型试验
数值模拟
界面
anti-slide pile
bedding slope with dual structure
model test
numerical simulation
interface
