中文摘要：

基于颗粒椭球体理论认为隧道上部松动区滑动面为椭圆形,据此推导出受滑动面倾角影响的侧土压力系数计算方法;在椭圆形松动区内竖向荷载沿水平向呈梯形分布,推导出隧道松动土压力计算方法。结果表明：当埋深低于极限椭圆高度时,松动区域为地面线以下的极限椭圆区域;当埋深达到极限椭圆高度时,松动区为整个极限椭圆,松动土压力不再增加。滑动面侧土压力系数是变化的,与滑动面倾角和土的摩擦角有关,随着内摩擦角增大而减小,随着滑动面倾角增大而增大。取值范围为0.2~0.8,介于主动土压力系数和Krynine侧土压力系数之间。本模型计算结果与实测数据较为吻合,可以用于隧道设计和施工中。

英文摘要：

Based on the ellipsoid theory of particle flows, that is, an dlipse sliding face is presented in the loosening zone at upper part of tunnels, a method is deduced to calculate the lateral earth pressure coefficient related to the inclination of sliding face. Besides, the method for calculating the loosening earth pressure is proposed in consideration of horizontal trapezium distribution of vertical loads in the loosening zone. The results show that the loosening zone behaves at the part of the limit ellipse under the ground line with the burial depth less than the height of the limit ellipse and a whole ellipse with the burial depth reaching the height of the limit ellipse, in which the earth pressure gets the maximum value. The lateral earth pressure coefficient is variable, and it has a positive correlation with sliding surface inclination, however, it has a negative correlation with friction angle. Usually, it values from 0.2 to 0.8 and ranges from the active coefficient to the Krynine coefficient. The proposed results are more close to the existing test data and model test data, and they can be used in the design and construction of tunnels.