开挖岩体边坡卸荷带宽度的计算方法

Calculation Method of Unloading Width for Excavated Rock Slopes

卸荷带的判别与计算,直接关系到岩体边坡的长期稳定性及致灾安全性。针对均质岩体边坡,采用弹性理论楔形体力学模型,提出了开挖岩体边坡力学模型,建立了开挖岩体边坡应力的计算方法;从开挖高度、开挖坡度、台阶宽度、岩体粘聚力、内摩擦角及岩体容重等方面,通过敏感性分析,探讨了开挖岩体边坡卸荷带宽度的变化规律,据此采用量纲分析法,建立了开挖岩体边坡卸荷带宽度的计算公式。

The discrimination of unloading zones influent the long-term stability and safety of rock slopes.For homogenous rock slope,the unloading mechanics model of excavated rock slope is got based on elastic wedge theory.The method used for calculating the width of unloading zones is deduced.Some parameters that affect the width of unloading zones,such as height,angle and width of excavation,cohesive strength,friction angle and density of rock mass are discussed through sensitivity analysis.Finally a formula is established to calculate the width of unloading zones by using dimensional analysis method.