SV波作用下刚性挡土墙地震主动土压力时频域计算方法

发布时间：2018-05-06 02:06

本文选题：土力学 + 刚性挡土墙　；参考：《岩石力学与工程学报》2014年03期

【摘要】：基于弹性波动理论,概化刚性挡土墙的动力分析模型,利用水平分层法,建立单元体的受力平衡微分方程,借助Hilbert-Huang变换,提出地震作用下刚性挡土墙地震主动土压力的时频域计算方法,并通过与振动台试验结果的对比验证该方法的合理性。分析输入波频率对刚性挡土墙墙后填土的临界破裂角、地震主动土压力合力以及作用点的影响,结果表明:随着地震烈度的增大,临界破裂角逐渐减小,地震主动土压力合力逐渐增大,合力作用点位置略有上移;随着输入波频率的增大,临界破裂角和地震主动土压力合力分别呈"倒马鞍型"和"正马鞍形"分布,并且均在输入波频率与刚性挡土墙系统自振频率相近时达到最大,而地震主动土压力合力的作用点则基本上不变;按照现有规范不考虑输入波频率进行刚性挡土墙地震稳定性设计,可能会降低挡墙的地震安全储备。刚性挡土墙地震主动土压力的时频域计算方法不仅能够考虑地震波三要素(峰值、频率以及持时)对挡墙土压力的影响,同时也能够为其他类型支挡结构的抗震时频设计提供一定的参考。
[Abstract]:Based on the elastic wave theory, the dynamic analysis model of the rigid retaining wall is generalized, the differential equation of the force balance of the unit body is established by the horizontal stratification method. With the help of the Hilbert-Huang transformation, the time frequency domain calculation method of the active earth pressure of the rigid retaining wall under earthquake is proposed, and the method is compared with the results of the shaking table test to verify the method. The effect of the input wave frequency on the critical fracture angle of the earth retaining wall after the rigid retaining wall, the resultant force of the active earth pressure and the action point of the earthquake shows that with the increase of the earthquake intensity, the critical fracture angle decreases gradually, the resultant force of the active earth pressure increases gradually and the position of the resultant force moves up slightly; with the frequency of the input wave In addition, the critical fracture angle and the active earth pressure joint force are "inverted saddle type" and "positive saddle" distribution respectively, and they all reach the maximum when the frequency of the input wave is close to the vibration frequency of the rigid retaining wall system, and the point of action of the joint force of the active earth pressure is basically unchanged. The seismic stability design of the retaining wall may reduce the seismic safety reserve of the retaining wall. The time frequency domain calculation method of the active earth pressure of the rigid retaining wall can not only consider the influence of the three elements of the seismic wave (peak, frequency and holding time) on the earth pressure of the retaining wall, but also provide the seismic time frequency design of other types of retaining structures. A certain reference.

【作者单位】：西南交通大学土木工程学院;
【基金】：交通运输部建设科技项目(2013 318 800 020) 2012年西南交通大学优秀博士学位论文培育项目专项资金项目
【分类号】：TU435;TU476.4

【参考文献】