摘要
设计并完成了相似比为1:10的框架锚杆支护黄土边坡的大型振动台模型试验,通过加载不同波型、加速度峰值和持时的地震波,探讨了地震作用下模型边坡的动力响应规律,并对框架锚杆支护结构的抗震性能进行了评价。试验结果表明:框架锚杆支护结构加固黄土边坡的抗震效果是显著的,在进行框架锚杆支护结构抗震设计时需要输入不同的地震波来验证其可靠性。框架锚杆支护结构作用下,黄土边坡对地震波具有明显的滤波作用和频谱放大作用,边坡加速度响应具有临空面放大作用和垂直放大作用,随着输入地震波峰值的增大,PGA放大系数呈减小趋势,在地震输入加速度峰值较小的情况下,加速度响应出现"衰减"现象;在框架锚杆支护下,黄土边坡的位移得到了有效的约束,动土压力分布曲线呈现"双曲线型"变化,动土压力大小沿高程方向从坡脚至坡顶呈倒三角形分布。试验结果可为框架锚杆支护结构加固黄土边坡的抗震设计提供一定的参考。
A large-scale shaking table experiment of loess slope supported by frame anchors with a 1:10 similarity ratio was designed and completed. By loading seismic waves of different types, acceleration peaks and durations, the dynamic response laws of model slope under earthquake action were discussed, and the seismic performance of the supporting structure with frame anchors was evaluated. The test results show that the anti-seismic effect of the supporting structure with frame anchors on the loess slope is significant. Different seismic wave inputs are used to verify its stability in the seismic design of the supporting structure with frame anchors. Under the action of the supporting structure, the loess slope has evident filtering effect on seismic waves and amplification effect on frequency spectrum, and the slope acceleration response has the amplification effect on the near-empty surface and vertical amplification effect. The acceleration response exhibits ‘attenuation’ phenomenon when the peak earthquake input acceleration is small. Under the support of frame anchors, the displacement of loess slope is effectively restrained, its dynamic earth pressure distribution curve shows ‘hyperbolic’ change, and the dynamic earth pressure is distributed in an inverted triangle from the foot of the slope to the top along the slope height direction. The test results can provide some reference for the seismic design of the supporting structures with frame anchors of loess slope.
作者
叶帅华
赵壮福
朱彦鹏
YE Shuai-hua;ZHAO Zhuang-fu;ZHU Yan-peng(Key Laboratory of Disaster Mitigation in Civil Engineering of Gansu Province,Lanzhou University of Technology,Lanzhou,Gansu 730050,China;Western Center of Disaster Mitigation in Civil Engineering,Ministry of Education,Lanzhou University of Technology,Lanzhou,Gansu 730050,China;Testing Center of Geotechnical Engineering and Foundation,Lanzhou,Gansu 730050,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2019年第11期4240-4248,共9页
Rock and Soil Mechanics
基金
国家自然科学基金项目（No.51768040）~~
关键词
黄土边坡
框架锚杆
动力响应
振动台试验
loess slope
frame anchors
dynamic response
shaking table test
