【作者】 孙兆刚；

【导师】 陈拴发；

【作者基本信息】 长安大学 ， 道路与铁道工程， 2010， 硕士

【摘要】 青海省干旱寒冷地区地处高原,气候变化急剧,冬长夏短、寒冷季节长,年平均气温较低、昼夜温差大,气候干燥、年平均降水量在250mm以下。该地区的沥青路面在如此严酷的气候环境下,容易出现低温开裂、半刚性基层干缩裂缝等病害。所以对青海省干旱寒冷地区沥青路面在其特殊气候环境下的力学状态进行分析,对该地区沥青路面结构设计有非常重要的意义。论文首先对青海省干旱寒冷地区的环境特征、交通量及交通组成、区内三条干线公路的沥青路面结构形式、沥青路面主要破坏类型等进行了调查,并根据上述调查结果分析该地区沥青路面破坏的原因。然后,在参考国内外相关文献和研究成果的基础上,以半刚性基层沥青路面为研究对象,采用ANSYS有限元软件,建立热-结构耦合二维有限元模型。计算沥青路面各结构层在温度循环作用下的温度应力,分析沥青面层厚度、沥青混合料温缩系数、沥青面层模量、日温差、基层厚度与模量对沥青路面各结构层温度应力的影响规律。并提出青海省干旱寒冷地区预切缝半刚性基层等沥青路面的结构形式,计算和分析该型路面结构在温度循环作用下不同预切缝间距的温度应力状况进行。最后,提出了预切缝半刚性基层沥青路面合理预切缝间距的确定方法和干旱寒冷地区沥青路面低温抗裂设计方法,确定干旱寒冷地区沥青路面低温抗裂设计流程。更多还原

【Abstract】 The arid and cold region in Qinhai province is located in plateau, rapid climate change, long cold season, the lower average annual temperature, higher diurnal temperature range, arid climate,250mm less average annual precipitation. Asphalt pavements in the region prone to low temperature and semi-rigid base shrinkage cracks. It is very practical significant that analysis the mechanical state of asphalt pavement of the arid and cold region in Qinghai province in its special climate conditions for this region’s asphalt pavement structure design.The thesis investigated the environmental characteristics, traffic volume and traffic composition, three trunk highways’asphalt pavemet main structures and damage types of the arid and cold region in Qinghai province. Based on these findings,the reasons of the asphalt pavement damage caused were analyzed. On the basis of a review of relevant literature and research, as the asphalt pavement for research object,the thesis uses the finite element software ANYSY, sets up thermal-structure coupling two-dimensional finite element model. Asphalt pavement thermal stress law that influenced by the thickness of asphalt surface,asphalt mixture temperature shrinkage index, modulus of asphalt surface, diurnal temperature range, thickness and modulus of base course was obtained, with calculating asphalt pavement thermal stress under temperature cyclings. Pre-cut semi-rigid base course asphalt pavement structure in the arid and cold region in Qinghai province is advanced. Thermal stresses of pre-cut semi-rigid base course asphalt pavement with different pre-cut spacing under temperature cycling are calculated and analyzed. Finally, the method for determining pre-cut semi-rigid base course asphalt pavement reasonable pre-cut spacing is advanced. And, design method of preventing low tempreature cracking in the arid and cold region is advanced. The design process for preventing low temperature crackinng in the arid and cold in Qinghai province is given.更多还原