加筋土挡墙屈服加速度与永久位移特性的拟动力法研究

摘要

Reinforced soil wall has super aseismic performance, which is widely used in slope reinforcement engineer of the seismic zones, but the mechanical behavior under the earthquake loads haven't a fully understanding.The traditional pseudo static method and factor of safety control design method can't consider the time history character of seismic acceleration, and it is inconsistent to the real seismic action.In this study, based on the kinematic theorem of limit analysis the seismic, combined with the Newmark theory, using the pseudo-dynamic method to consider the time history character of seismic acceleration, the expressions of the yield acceleration and the permanent displacement of reinforced soil wall is derived.We then analyze the dynamic response of the reinforced soil wall.At last, a case is used to illustrate the method.The critical seismic yield acceleration coefficient and the seismic permanent displacement of reinforced soil wall under seismic loading are calculated.Meanwhile, the effect of the horizontal seismic acceleration and vertical acceleration effect on the stability of the slope with reinforced soil wall is analyzed.The comparison is made with the pseudo-static method.The results has shown that the pseudo-static method may give a conservative design for reinforced soil wall, it may cause unnecessary waste and not economically.%加筋土挡墙具有良好的抗震性能,广泛应用于地震带边坡加固防护工程,但是其强震荷载下的力学行为仍未有全面认识.而传统的拟静力法和安全系数控制设计方法不能考虑地震加速度时程特征,与地震作用的真实情况不符.该文在极限分析上限定理的基础之上,结合Newmark理论,采用拟动力法,考虑地震加速度的时程变化特征,推导计算加筋土挡墙屈服加速度与永久位移的计算公式,研究地震作用下加筋土挡墙的动力响应.最后通过算例对该方法进行了验算,计算分析地震作用下加筋土挡墙的屈服加速度与永久位移,研究水平地震加速度和竖向地震加速度对加筋土挡墙稳定性的影响.并与传统的拟静力方法结果进行对比,研究结果显示:拟静力法设计的加筋土挡墙可能偏于保守,可能造成不必要的浪费,经济上不合理.