泥石流作用下路基易损性模型试验研究

目的]采用模型试验研究泥石流对路基的冲淤作用规律,为泥石流作用下路基易损性的研究提供一定依据。方法]以中巴公路K1561泥石流沟谷为研究原型,应用相似试验原理建立模型。根据原型沟谷设置试验条件,得到原型沟谷模型试验数据;然后又采用控制变量法进行6个因素共25组模型试验,以研究不同因素在泥石流作用下对公路路基的冲淤作用规律。结果]原型沟谷模型试验数据与现场调查结果相吻合;流通区坡度、路基与泥石流出山口之间的距离、一次泥石流冲出物最大方量、泥石流重度和泥石流爆发频率5个因素对易损性的影响较为明显,泥石流主沟道与路基之间的夹角对路基易损性的影响不明显。结论]5个因素对路基易损性有重要影响,可作为泥石流易损性评价中的重要评价指标。

Model Test of Subgrade Vulnerability Under Debris Flow

Objective] To provide a basis for studying the vulnerability of subgrade under the action of debris flow, model test is used to research the scouring and silting mechanism of the debris flow on the subgrade.Methods] The debris flow gully in China-Pakistan K1561 highway was selected as the research prototype. A similar test model of the debris flow gully was built. Test data was obtained from the simulation of the prototype valley. The scouring and silting mechanism of highway subgrade was studied by control variate method, based on the model tests performed on 6 factors of 25 groups.Results] The results of prototype gully model test were in good agreement with the field investigation results. Five factors, namely circulation area slope, the distance between the subgrade and the mountain pass, the maximum amount, the severity and the frequency of debris flow, showed obvious impacts on the subgrade vulnerability, while the influence of the angle between the main channel and the subgrade was not significant.Conclusion] Five factors have important influences on subgrade vulnerability, and can be used as important evaluation indexes for debris flow vulnerability assessment.