摘要
在沥青混凝土路面局部较小范围内,往往同时含有表面裂纹和反射裂纹,本文从室内试验的角度研究了表面裂纹对反射裂纹扩展的影响。在试件表面和底面预制裂纹来模拟路面沥青混凝土实际情况,通过弯曲试验演示裂纹扩展情况。试验结果表明,表面裂纹对反射裂纹的起裂角、扩展路径、砼弯拉强度都有影响:起裂角度大小与间距有关,一般随间距增大,先增大后减小;起裂方向与表面裂纹的方位一致;如果将扩展路径分为初始阶段、调整阶段、最终阶段,表面裂纹对初始阶段影响最大,裂纹斜向起裂,随后逐步调整为竖向,使扩展路径呈明显的曲线状;试件弯拉强度随间距的增大,先减小后增大。
The surface crack and the reflect crack are usually existed simultaneously in a small local range of the asphalt concrete pavement.In this paper,the influences of the surface crack on the propagation of reflect crack via laboratory test were studied.The pre-crack on both the surface and underside of the specimen was set to simulate the actual situation of asphalt concrete pavement,the crack propagation via bending test was then studied.The results show that the initiation angle,propagation path and flexural tensile strength are affected by the surface crack.The initiation angle is generally increased with the distance,increase at first and then decrease;the initiation direction is the same as the orientation of surface crack.If we divide the propagation into three stages： the initiation stage,the adjustment stage and the final stage,it can be found that the propagation path was affected mostly in the initiation stage by the surface crack.Diagonal crack was initiated,then gradually adjusted to the vertical,which makes the propagation path shaped as curve obviously;the flexural tensile strength of specimen decreased at first and then increased with the distance.
出处
《土木工程与管理学报》
2011年第1期20-23,共4页
Journal of Civil Engineering and Management
基金
国家自然科学基金(50908093)
关键词
表面裂纹
起裂角
扩展路径
弯拉强度
试验研究
surface crack
initiation angle
propagation path
flexural tensile strength
experimental study
