季冻区公路风积雪的研究与防治

发布时间：2019-01-25 19:16

【摘要】：风积雪是季冻区常见的一种气流混杂雪粒的湍流运动，灾害发生时，雪粒飞舞，路面能见度急剧降低，驾驶员无法正确判断路面行驶状况，极易引发交通事故；路面、路侧产生大量的积雪，轻则阻塞交通，重则交通线路直接瘫痪，造成巨大的经济损失；除雪过程再次加重了交通的拥堵，而且对路面、路面设施造成明显损坏，影响使用寿命，降低了安全系数。研究风积雪灾害的发展与分布规律，对于提高季冻区道路行车安全性和道路耐久性有重要的理论价值和现实意义。本文在总结前人研究成果的基础上，首先研究了雪粒的受力形态，找到雪粒沉积的动力因素是风速的梯度变化，进而知道雪粒沉积分布和风速流场分布密切相关。分析了风积雪产生的物质和动力条件，进一步研究了风积雪从雪粒起动到雪流饱和的全过程，并给出了相关计算公式。接着从自然条件和道路参数两方面研究了风积雪灾害的影响因素，主要是研究了不同因素导致风速的变化、起动条件的变化、雪流形态的变化。论文以吉林省为例，分析了季冻区的气候特点和时空分布规律，主要是风积雪害多发的春冬季节，季冻区的气温、气压、风速、降水、降雪时空分布；分析了风积雪害地区，雪流自身的垂直和水平分布规律。论文通过建立Fluent流体力学模型，将风积雪流二相湍流的分析转换成纯空气场单相湍流的分析，分析不同路基断面形式下，路面附近空间的风速流场变化，找到风速减速区，运用计算流体力学，确定了水平加速度和积雪线分布，从而找到雪粒的沉积规律。最后，论文研究了季冻区积雪公路的防雪、治雪措施，并对常见的防雪设施的作用机理做了分析，，并提出了设置时应注意的问题和相关建议参数。本文研究成果将为季冻区公路风积雪灾害的预防和治理提供理论和技术支持。
[Abstract]:Wind and snow cover is a kind of turbulent motion of air flow mixed with snow particles in seasonal frozen area. When the disaster occurs, snow particles fly, the visibility of road surface is reduced sharply, the driver can not correctly judge the driving condition of the road surface, so it is easy to cause traffic accidents. Road surface, side of the road produced a large amount of snow, light traffic congestion, heavy traffic lines directly paralyzed, resulting in huge economic losses; The snow removal process once again aggravated the traffic congestion, and caused obvious damage to the pavement and pavement facilities, which affected the service life and reduced the safety factor. It is of great theoretical and practical significance to study the development and distribution of wind-snow disasters for improving road safety and road durability in seasonal frozen areas. On the basis of summarizing the previous research results, this paper first studies the force form of snow particles, finds out that the dynamic factor of snow particle deposition is the gradient change of wind speed, and then knows that the distribution of snow grain deposition is closely related to the distribution of wind velocity flow field. The material and dynamic conditions of wind-snow cover are analyzed, and the whole process from the start of snow particles to the saturation of snow flow is further studied, and the relevant calculation formulas are given. Then the influence factors of wind-snow disaster are studied from two aspects of natural conditions and road parameters, mainly the change of wind speed caused by different factors, the change of starting condition and the change of snow flow shape. Taking Jilin Province as an example, this paper analyzes the climatic characteristics and temporal and spatial distribution of seasonal frozen areas, mainly in spring and winter seasons where wind and snow damage occur, and the temperature, air pressure, wind speed, precipitation and snowfall in seasonal frozen areas. The vertical and horizontal distribution of snow flow in wind-snow damage area is analyzed. By establishing Fluent hydrodynamic model, the analysis of two-phase turbulence of wind-snow flow is transformed into the analysis of single-phase turbulence in pure air field, and the variation of wind velocity flow field in the space near the road surface is analyzed under different roadbed cross-sections, and the wind speed deceleration zone is found. The horizontal acceleration and snow line distribution are determined by computational fluid dynamics (CFD), and the deposition rule of snow particles is found. Finally, the paper studies the snow prevention and snow control measures of snow highway in seasonal freezing area, analyzes the mechanism of common snow prevention facilities, and puts forward some problems that should be paid attention to when setting up and the relevant suggestions. The research results in this paper will provide theoretical and technical support for the prevention and control of highway wind-snow disasters in seasonal frozen areas.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U418.41

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