地震作用下动孔隙水压力对边坡永久位移影响的简便计算方法  

Simple calculation method of permanent displacement of slope influenced by dynamic pore water pressure under earthquake

作　　者：黄帅[1] 宋波[1] 牛立超[1] 叶阳升[2] 蔡德钩[2] 

机构地区：[1]北京科技大学土木与环境工程学院,北京100083 [2]中国铁道科学研究院铁道建筑研究所,北京100081

出　　处：《建筑结构学报》2014年第3期215-221,共7页Journal of Building Structures

基　　金：国家高技术研究发展计划专项经费项目(2011AA11A102);高速铁路轨道技术国家重点实验室开放课题基金项目(2012SKL01);教育部海外名师项目(MS2011BJKJ005);科技部科研院所技术研究专项基金项目(2012EG123027)

摘　　要：基于转动平衡理论,提出了考虑地震作用下动孔隙水压力影响的边坡永久位移简便计算方法,并通过砂土边坡(长度×宽度×高度为1.96 m×0.96 m×1.20 m)的振动台试验进行了验证。结果表明:地下水对边坡动力特性影响较大,随着地下水位的升高,边坡的自振周期呈现增加趋势,水位1.0 m时边坡的自振周期是无水时的2.88倍;地下水位越高,地下水对边坡临界加速度的影响越显著,且当水位为1.0 m时边坡的临界加速度比无水时减小了28%;随着水位的升高,边坡永久位移均表现出增加的趋势,地震峰值加速度为2.0 m/s2时,水位1.0 m的永久位移是无水时的9.8倍;此外,随着地震峰值加速度的增加,边坡永久位移急剧增加,当地震峰值加速度为2.0 m/s2时,永久位移是地震峰值加速度为1.0 m/s2时的6.9倍。建议的简便方法与试验测得的边坡永久位移最大偏差在10%以内,验证了建议方法的可靠性。Based on the theory of rotation equilibrium, a simple calculation method for the permanent displacement of the soil slope considering the influence of dynamic pore water pressure under earthquake was put forward, and the method was verified by shaking table test of the soil slope （ 1.96 m × 0. 96 m × 1.20 mofL ×W × H）. The results show that groundwater has a greater impact on dynamic characteristics of the slope, and the natural vibration period with i. 0 m groundwater depth is 2.88 times of that without groundwater. The influence of groundwater on critical acceleration is more significant with the increase of groundwater depth, and the critical acceleration with 1.0 m groundwater depth is reduced by 28 % compared with no water. With the increase of water depth, slope of permanent displacement shows an increasing trend. When the peak acceleration of earthquake is 2.0 m/s2, the permanent displacement with full water depth is 9. 8 times of that without water. In addition, with the increase of peak acceleration, the permanent displacement increases dramatically. Permanent displacement with peak acceleration of 2.0 rn/s2 is 6. 9 times of that with the peak acceleration of 1.0 m/s2. Compared with the permanent displacements measured by test, the deviation are within 10%, which shows the suggested simple method is accurate.

关 键 词：边坡 地震作用 地下水 转动平衡理论 振动台试验 永久位移 

分 类 号：TU435[建筑科学—岩土工程]