岩石边坡植被恢复工程中的客土稳定性分析

目的]讨论岩石边坡植被恢复工程中的客土稳定性计算方法,为该类工程的稳定性评价提供依据。方法]模拟计算抗剪型和摩擦型根系产生的作用力,转换为抗剪强度后作为客土稳定性的附加值,进而推导出稳定性计算公式,并通过济南—莱芜高速公路的客土喷播工程案例进行实测和验证。结果](1)客土稳定性系数取决于无根土抗剪强度(Fs)、客土容重(γ)、客土厚度(d)、根系抗剪强度增量(τR);(2)根系产生的抗剪强度可细分抗剪型根系抗剪应力(τRg)和摩擦型根系抗剪应力(τRf)二者之和;(3)稳定性计算值始终小于实测值,分布规律及偏差值较稳定,植被恢复初期的3~5a内客土稳定性系数与植被恢复期成明显的正相关关系。结论]客土稳定性系数计算可以作为岩石边坡植被恢复工程的参数设计和稳定性评价方法。

Stability Analysis of Carrying Soil in Vegetation Restoration Project on Rock Slope

Objective] The calculation method with regard to the carrying soil stability in a vegetation restoration project performed on the rock slope was discussed.Methods] The acting forces both from resisting shear root and friction root were simulated,and then converted them into anti-shear strength and served as an added value to the stability of carrying soil.Further,a mathematical model associated with the soil stability on the rock slope was established,and was verified by the vegetation restoration project of the Jinan-Laiwu expressway.Results] (1) The stability coefficient of carrying soil was a function of shear strength without root(Fs),bulk density(γ),thickness(d),and increment of root shear strength(τR).(2) The anti-shear strength of the root could be the sum of resisting shear root(τRg) and friction root(τRg).(3) The stability coefficient is persistently smaller than its measured counterpart,and the deviation rate is small.Also,the soil stability coefficient was positively correlated with the initial vegetation restoring period (i.e.3～5 years).Conclusion] The determination of carrying soil stability coefficient could be employed as the parametric design and evaluation for the vegetation restoration project on the rock slope.