施工期水泥稳定碎石底基层的疲劳损伤分析  

Fatigue damage analysis of cement stabilized sub-base during construction period

作　　者：房娜仁 胡士清 王选仓[2] 李琪琪 辛磊 FANG Naren;HU Shiqing;WANG Xuancang;LI Qiqi;XIN Lei(School of Civil Engineering,Tianjin Chengjian University,Tianjin 300384,P.R.China;School of Highway,Chang an University,Xi an 710064,Shaanxi Province,P.R.China)

机构地区：[1]天津城建大学土木工程学院,天津300384 [2]长安大学公路学院,陕西西安710064

出　　处：《深圳大学学报（理工版）》2021年第1期61-68,共8页Journal of Shenzhen University(Science and Engineering)

基　　金：交通运输部重点科技资助项目(2018-MS2-042);交通运输部科技示范工程资助项目(2017-04)。

摘　　要：水泥稳定碎石材料用做路面基层及底基层时,由于施工期养生龄期不足和车辆荷载超载,会造成不可逆疲劳损伤.为得到施工荷载对水泥稳定碎石底基层造成的疲劳损伤,基于Miner理论和ABAQUS软件,进行弯拉强度试验和疲劳试验,分析了9种车辆荷载下,底基层厚度分别为16、20、24、28和32 cm时,最大层底拉应力与底基层厚度的关系,以及底基层模量分别为400、800、1200、1600和2000 MPa时,最大层底拉应力与底基层模量的关系.研究结果表明,随着底基层厚度的增加,底基层层底拉应力不断减小,减小率最大为8.8%;随着底基层模量的增加,底基层层底拉应力不断增大,但增长率不断降低.依托实际工程,可得到水泥稳定碎石底基层疲劳预估方程,基于Miner理论计算得到不同工况下,不同施工荷载对底基层造成的疲劳损伤程度,为路面设计和施工提供指导.When cement stabilized gravel materials are used as pavement base and sub-base,irreversible fatigue damage often occurs due to insufficient maintenance days during the construction period and overload of vehicle load.In order to obtain the fatigue damage caused by the construction load on the cement stabilized gravel sub-base,the flexural tensile strength test and the fatigue test are carried out based on Miner theory and ABAQUS software.Under 9 kinds of vehicle load,we analyze both the relationship between the maximum tensile stress of the sub-base layer and the substrate thickness when the substrate thickness is 16,20,24,28,and 32 cm and the relationship between the maximum tensile stress of the sub-base layer and the modulus of the sub-base when the modulus of the subbase is 400,800,1200,1600,and 2000 MPa,respectively.The research results show that with the increase of the thickness of the sub-base layer,the tensile stress of the sub-base decreases gradually,and the maximum reduction rate is 8.8%.With the growth of the sub-base modulus,the bottom tensile stress of the sub-base layer increases gradually,but the growth rate continues to decrease.Relying on the actual engineering project,the fatigue prediction equation of the cement stabilized gravel sub-base can be obtained by using Miner theory to calculate the fatigue damage degree of the subbase caused by different construction loads under different working conditions,which provides guidance for the design and construction of the pavement.

关 键 词：道路工程 疲劳损伤分析 疲劳方程 Miner理论 水泥稳定碎石 底基层 

分 类 号：U416.2[交通运输工程—道路与铁道工程]