双江口心墙堆石坝地震加速度反应的振动台模型试验研究
|
摘要
本文通过不同地震波输入的振动台模型试验,得到模型坝的加速度分布资料,研究测点位置、台面地震波强度、地震波类型、多向输入、先期振动和蓄水等因素对加速度放大倍数分布的影响。研究表明:(1)坝体地震动加速度反应在河谷坝段最为强烈,且随所处坝体部位高度的增加而增强;(2)对相同高程上各点,以中心线坝体测点加速度反应最小,上、下游次之,整个坝体的表面放大效应明显;(3)地震波类型对加速度放大倍数和分布有重要影响,集中体现在地震波卓越频率与坝体自振频率的关系上;(4)随输入地震峰值加速度的增大,坝体各点加速度放大倍数有减小的趋势;(5)垂直方向(z向)地震动有加大顺河水平向(x向)加速度反应的作用,特别是在坝顶表现比较明显;(6)先期振动会引起坝体后续地震动加速度反应的增大;(7)坝体的加速度反应在空库时比满库蓄水时强烈。
Through shaking table model tests,the seismic acceleration response and its influencing factors of the Shuangjiangkou high earth-rockfill dam,including sampling locations,seismic peak ground acceleration,directions of seismic waves,pre-vibrations and reservoir filling,are studied.Results show that:(1) The acceleration is the strongest on the main section of the dam and increases with height;(2) At the same height,the acceleration is the weakest on the dam axis,and it gradually increases upstream-ward or downstream-ward.Surface amplification effect is significant;(3) The type of seismic waves has a great impact on acceleration magnification and its distribution,particularly on the relationship of the dominant frequency of inputted wave versus the dam 's natural frequency;(4) Acceleration magnification shows a decreasing trend as the peak ground acceleration increases;(5) Vertical seismic ground vibration causes an increase in stream-wise acceleration,especially at the dam crest;(6) Pre-vibrations intensify the seismic acceleration;(7) Reservoir filling has a considerable impact on seismic acceleration,the response without water is stronger than full of water.
Through shaking table model tests,the seismic acceleration response and its influencing factors of the Shuangjiangkou high earth-rockfill dam,including sampling locations,seismic peak ground acceleration,directions of seismic waves,pre-vibrations and reservoir filling,are studied.Results show that:(1) The acceleration is the strongest on the main section of the dam and increases with height;(2) At the same height,the acceleration is the weakest on the dam axis,and it gradually increases upstream-ward or downstream-ward.Surface amplification effect is significant;(3) The type of seismic waves has a great impact on acceleration magnification and its distribution,particularly on the relationship of the dominant frequency of inputted wave versus the dam 's natural frequency;(4) Acceleration magnification shows a decreasing trend as the peak ground acceleration increases;(5) Vertical seismic ground vibration causes an increase in stream-wise acceleration,especially at the dam crest;(6) Pre-vibrations intensify the seismic acceleration;(7) Reservoir filling has a considerable impact on seismic acceleration,the response without water is stronger than full of water.
引文
[1]刘小生,王钟宁,汪小刚,等.面板坝大型振动台模型试验与动力分析[M].北京:中国水利水电出版社,2005,40～41.LIU Xiaosheng,WANG Zhonning,WANG Xiaogang,et al.Large scale table model tests and dynamic analysis of CFRD[M],2005,40～41.(in Chinese).
[2]刘启旺,刘小生,陈宁,等.双江口心墙堆石坝振动台模型试验研究[J].水力发电学报,2009,28(5):114～120.LIU Qiwang,LIU Xiaosheng,CHEN Ning,et al.Shaking table model tests of Shuangjiangkou high earth-rockfill dam[J].Journal ofHydroelectric Engineering,2009,28(5):114～120.(in Chinese).
[3]刘小生,刘启旺.双江口大坝振动台模型试验研究报告[R].北京:中国水利水电科学研究院,2009.LIU Xiaosheng,LIU Qiwang.Shaking table tests of Shuangjiangkou dam[R].Beijing:China Institute of Water Resources andHydropower Research,2009.(in Chinese)
[2]刘启旺,刘小生,陈宁,等.双江口心墙堆石坝振动台模型试验研究[J].水力发电学报,2009,28(5):114～120.LIU Qiwang,LIU Xiaosheng,CHEN Ning,et al.Shaking table model tests of Shuangjiangkou high earth-rockfill dam[J].Journal ofHydroelectric Engineering,2009,28(5):114～120.(in Chinese).
[3]刘小生,刘启旺.双江口大坝振动台模型试验研究报告[R].北京:中国水利水电科学研究院,2009.LIU Xiaosheng,LIU Qiwang.Shaking table tests of Shuangjiangkou dam[R].Beijing:China Institute of Water Resources andHydropower Research,2009.(in Chinese)
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心