考虑挡土墙位移模式的地震主动土压力拟动力研究

发布时间：2018-06-20 01:38

本文选题：拟动力法 + 斜层分法　；参考：《南京大学》2013年硕士论文

【摘要】：地震土压力的计算是一个很复杂的系统性问题,所以尽管从M-0理论提出至今,很多学者对此采用了不同的方法进行了研究,取得了丰硕的成果,但有许多问题还是无法得到圆满的解答,所以这仍是一个值得继续研究和探讨的领域。本文基于M-0破裂面假设,采用拟动力法的地震力施加方式,结合土压力计算的斜层分法,探讨了不同位移模式下的地震主动土压力,并取得了以下成果：(1)推导了一般挡土墙的地震主动土压力计算公式,考虑了地震加速度的放大效应,并对粘性土填土表面的张拉裂缝对公式进行了修正。运用此公式能够获得地震卓越周期内任意时刻的地震主动土压力分布、合力以及作用点位置。其适用于粘性土、无粘性土、不同的墙背形式(仰斜、垂直、俯斜)、表面填土存在倾角、有无均布超载等复杂情况下的地震土压力计算。并分析了各因素对临界滑裂面倾角、地震主动土压力合力、合力作用点高度和土压力分布的影响。(2)推导出一般挡土墙的采用拟动力法的库伦地震主动土压力和采用拟静力法的层分地震主动土压力公式,并将本文介绍的方法与这两种方法进行了比较,得到各种方法计算结果的差异性。(3)总结前人得到的不同位移模式下填土以及墙土间的强度参数与土体位移的数值关系,利用本文推出的地震主动土压力公式,得到挡土墙不同位移模式下的地震主动土压力及其分布随位移的渐进变化。(4)具体的工程实例表明,挡土墙适量的位移量能够使墙后土体的强度得到充分发挥,从而减小所受到的地震主动土压力,提高挡土墙的抗震稳定性。
[Abstract]:The calculation of seismic earth pressure is a very complicated and systematic problem, so although from the point of view of M-0 theory, many scholars have adopted different methods to study it, and have achieved fruitful results. However, there are still many questions that cannot be satisfactorily answered, so this is still an area worthy of further study and exploration. Based on the hypothesis of M-0 fracture surface, the seismic active earth pressure under different displacement modes is discussed by using the pseudo-dynamic method and the oblique layer method of earth pressure calculation. The following results are obtained: 1) the formula of seismic active earth pressure of general retaining wall is derived, the amplification effect of seismic acceleration is considered, and the formula of tension crack on clay fill surface is modified. By using this formula, the active earth pressure distribution, the resultant force and the position of the active earth pressure can be obtained at any time during the period of earthquake excellence. It is suitable for the calculation of seismic earth pressure under complex conditions such as clayey soil, clayless soil, different wall back forms (inclined, vertical, overloaded or not). In addition, the influence of various factors on the slope angle of critical slip surface and the resultant force of active earth pressure in earthquake are analyzed. (2) the formula of active earth pressure of Coulomb earthquake using pseudo-dynamic method and active earth pressure of stratum seismic using pseudo-static method is derived. The comparison between the two methods is made, and the difference of calculation results between these two methods is obtained. The numerical relationship between the strength parameters of the wall and soil and the soil displacement under different displacement modes is summarized. By using the formula of seismic active earth pressure derived in this paper, the progressive variation of seismic active earth pressure and its distribution with displacement under different displacement modes of retaining wall are obtained. The proper displacement of retaining wall can give full play to the strength of soil behind the wall, thus reducing the earthquake active earth pressure and improving the seismic stability of retaining wall.
【学位授予单位】：南京大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU432

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