【作者】 赵镇君；

【导师】 胡幼常；

【作者基本信息】 武汉理工大学 ， 道路与铁道工程， 2010， 硕士

【摘要】 我国的高速公路,绝大多数面临着重载车多,超载严重的实际情况。同时为了充分利用地材以降低造价原因,基本上都采用半刚性材料为基层沥青路面结构,所以在通车后不久路面就会出现明显的车辙和大量的反射裂缝。一些研究资料表明,采用含大粒径沥青混合料基层的沥青路面结构有望很好地解决这个问题。但这方面的研究还不充分,这种路面结构在实际工程中应用也很少。因此对其进行广泛深入的研究是非常必要的。基于上述理由,结合武汉至鄂州高速公路的工程建设,修筑了含大粒径沥青碎石混合料ATB-30基层的试验路。试验路全长600 m,分A、B、C三段。A段路面结构为：46 cm水泥碎石+10 cm ATB-30+8 cm AC-25+6 cm AC-20+4 cm AC-13;B段路面结构是在A段的水泥碎石下基层顶面加铺一层玻纤格栅,其他与A段路面结构相同；C段路面结构为：44 cm水泥碎石+20 cm ATB-30+ 6 cm AC-20+4 cm AC-13。在各段试验路的土基顶面和水泥碎石下基层顶面埋设了土压力盒,在沥青碎石基层(ATB-30)的底面和顶面埋设了光纤光栅应变传感器。通过承载板进行了现场静载荷试验,以不同载重的大货车以不同的速度通过试验路段完成了动载试验。通过埋设的应力和应变测量元件,测量了试验段各路面结构层的应力和应变响应。在此基础上,建立了上述路面结构的力学计算模型,用ANSYS软件进行了数值分析,计算结果得到了试验数据的验证。根据该数值计算模型,对大粒径沥青碎石基层路面力学性能,特别是在重载交通荷载下的应力、应变分布规律进行了深入分析,证明该路面结构具有良好的抗剪切流变抗压缩变形能力,因此具有良好的抗车辙性能。更多还原

【Abstract】 A lot of vehicles running on expressway in China are heavy axle-load trucks, most of which are severely over-loaded. Nearly all of the expressways are covered with asphalt pavement including a semi-rigid base for economic reason. Therefore damage of rutting and reflection cracks is usually observed in their early service period. It has been proved by some researches that an asphalt pavement including large-stone asphalt mixes (LSAM) base is expected to overcome the problem. But it has not been accepted widely in practice in China because the research until nowadays is not efficiently. For this reason, the mechanical response of asphalt pavement including LSAM base is studied by field experiment.The experimental LSAM pavement which is 600 m long was constructed in Wuhan-Ezhou Expressway. It includes three sections named respectively as A, B and C. The structure layers of section A is:46 cm cement gravel+10 cm ATB-30+8 cm AC-25+6 cm AC-20+4 cm AC-13. Beside having the same layers of section A, section B has a glass fiber grid at the interface of cement gravel and ATB-30. Section C consists of 44 cm cement gravel+20 cm ATB-30+6 cm AC-20+4 cm AC-13.Pressure cells were placed both at the top of soil subgrade and at the top of the cement gravel. At the bottom of ATB-30 and the bottom of AC-25 (for section A and section B) or AC-20 (for section C) fiber grating based (FBG) sensors were embedded for strain measurement.Static load tests were carried out by loading plate. A series of traffic load tests were demonstrated by moving trucks under different tire loads. During the static and traffic load tests, the internal pressures and strains of the pavement structure were both measured. Based the analysis of the test data, the mechanical properties of asphalt pavement including LSAM base is discussed. A FEM model which gives a result coinciding with the field experiment, is then proposed by ANSYS Program to conduct a detail analysis on the response of this kind of pavement under traffic loading. The experimental and numerical analysis results prove that asphalt pavement including LSAM base has a good performance against rutting and reflection cracking.更多还原