地震荷载下的土压力线性分布解

Mononobe-Okabe土压力理论广泛应用于地震效应下的土压力计算,但由于其理论基础为库伦理论,因而只能计算土压力合力。基于Mononobe-Okabe土压力理论的平面滑裂面假设,在拟静力分析法的基础上采用斜向条分法,推导了考虑多种复杂条件下的地震土压力合力及其作用点位置、土压力强度计算式,并给出临界破裂角的显式解答。分析表明:斜向条分法能够有效验证Mononobe-Okabe理论假设土压力强度沿墙高线性分布的合理性,且在相应简化条件下,该公式给出的土压力合力与Mononobe-Okabe理论的计算结果完全一致。通过探讨水平和竖向地震荷载对土压力的影响初步获得了地震土压力的变化规律。

Calculation of Linear Earth Pressure under Seismic Load

The Mononobe-Okabe earth pressure theory is widely used in seismic earth pressure calculation, but it can only calculate the earth pressure resultant forces. Based on the sliding plane hypothesis of Mononobe-Okabe earth pressure theory, on the basis of pseudo static analysis, diagonal slice method is used to deduce the formula of resultant force of seismic earth pressure and its application position, and the formula of the intensity of earth pressure under multiple complex conditions, the critical rupture angle of the explicit solutions is also deduced. The formula can effectively prove the rationality of Mononobe-Okabe theory’s assumption that the earth pressure behind retaining wall is in linear distribution, besides the resultant force, that this formula gives, is the same with the result that the Mononobe-Okabe theory offers under corresponding simplified conditions. By discussing the influence the horizontal and vertical seismic load has on earth pressure, the preliminary regularities of the change of seismic earth pressure is obtained.