高速公路路堑风雪流灾害预测模型与应用

山区高速公路在风雪天气极易出现风雪流灾害,造成雪阻路断,影响正常通行。复杂的地形和路基断面往往是引导风雪流流向和雪粒沉积的关键因素,尤其路堑形式下,路面积雪更为严重。本文针对全路堑、迎风半路堑和背风半路堑三种路堑形式,对风雪流流场进行了数值模拟,分析流场的分布规律和雪害致灾机理。选定路面积雪范围为目标函数, 以山体相对高度、路基与山体横向距离、路堑深度、路堑坡度及风速为主要影响因素,对大量案例进行了正交试验和回归分析,获得了路堑积雪的预测模型。该模型经过了显著性检验,可反应各因素对路面积雪影响程度的大小, 并能体现各因素对路面积雪的耦合作用。最后,结合具体工程实例,对所建立的模型进行了应用与验证分析,发现预测模型与数值模拟结果误差不超过5%,验证了模型的有效性和实用性。

Prediction Model of Snow Drifting Disaster in Expressway with Cuttingand Its Application

Snow drafting is a common seen meteorological disaster in expressways in mountainous areas of Northern China, and the blocking of snow often affects the normal transportation in the expressway. The complex terrain and the roadbed cross-section are the key factors which guide the direction of the wind and the sedimentation of the snow, especially for the expressway with cutting form, the snow sedimentation on the surface of the road is extremely serious. In this paper, the flow field of the snow drifting in expressways with whole cutting, windward half cutting, and leeward half cutting were simulated, the distribution pattern of the wind velocity and the mechanism of the snow drifting disaster were analyzed. The range of snow cover on the road surface was selected as the objective function, and the relative height of the mountain, the transverse distance between the roadbed and the mountain, the depth of the cutting, the slope of the cutting and the wind speed were the main influencing factors. On this basis, extensive orthogonal experiment and the regression analysis were conducted for ample cases, and the prediction models of the snow drifting disaster were established. The proposed models pass the significant test, which can reflect the influence degree of each factor on the road snow, and can reflect the coupling effect of each factor on the road snow. In the end, combined with a concrete engineering