摘要
从力学角度出发,以路基在长期交通荷载作用下不至于变形过大为主要目的,利用动变形控制法,针对路基高度与湿度的相互关系进行了研究。首先,通过室内试验获得了路基土体回弹模量与湿度及压实度的定量关系式;同时基于层状公路结构动力响应解及路基、路面协调变形原理,获得了路基顶面动变形控制标准。结合试验结果和路基顶面动变形控制标准,建立了路基湿度、压实度与路基高度之间的联系。最后,以两种典型沥青混凝土公路结构为例,编制程序进行了数值计算,分析了满足动变形条件下的路基临界高度随路基湿度、压实度的变化规律。结果表明:路基临界高度随着路基湿度的增加而增大。路基湿度低于最优含水率时,路基临界高度随路基湿度和压实度的变化均较小;路基湿度高于最优含水率时,路基临界高度迅速增大,且压实度对临界高度的影响也变得十分显著。研究结果为路基高度和湿度的合理取值提供了新的思路。
In order to control the deformation of subgrade under long-term traffic load, the dynamic deformation control method is employed to study the relationship between the critical height and the humidity of subgrade from the viewpoint of mechanics. Firstly, a quantitative formula of resilient modulus, humidity and compactness is obtained according to the result of laboratory resilient modulus test. Then, combining the solutions of dynamic response of the multilayered subgrade structures and the principal of compatibility of deformation between pavement and subgrade, the allowable value of dynamic deformation of subgrade top is derived. Based on the quantitative formula and the control standard of dynamic deformation of subgrade top, the relationships among the critical height, humidity and the compactness are built up. Finally, numerical results are obtained by taking two typical asphalt pavement structures for example. It is shown that, the critical height of subgrade increases with the increasing humidity. Both of the subgrade humidity and the compactness have little effect on the critical height of subgrade when the subgrade humidity is less than the optimum water content. However, when the subgrade humidity is more than the optimum water content, the critical height of subgrade increases sharply with the increasing humidity; and the effect of the compactness on the critical height becomes significant. The results provide a new idea for reasonable value of the subgrade height and humidity.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2014年第1期184-188,共5页
Rock and Soil Mechanics
基金
国家自然科学基金(No.51209201
No.51279198)
武汉市青年科技晨光计划项目(No.201150431070)
西部交通建设科技项目(No.2011318493720
No.20113184931700)
关键词
动变形控制
长期交通荷载
层状公路结构
路基临界高度
路基湿度
dynamic deformation control
long-term traffic load
multilayered road structure
critical height of subgrade
subgrade humidity
