盐冻作用下水泥路面毛细吸水系数演化及应力状态分析

Evolution of capillary water absorption coefficient and stress stateanalysis of cement pavement under salt freezing

为探究道面混凝土毛细孔吸水系数与损伤度之间的关系,开展了室内盐冻试验,以冻后混凝土为对象进行毛细吸水试验及力学性能测试,对高寒季冻区在役期水泥路面的路用性能指标控制进行分析。结果表明:混凝土毛细吸水系数与冻融循环次数及损伤度之间均具有较强的非线性关系;外部湿润对道面混凝土的影响深度随盐冻次数的增大而增大,当混凝土损伤度D达到0.13时,湿度影响范围增大20%;相较于抗弯折强度损失,盐冻损伤导致的道面混凝土自身湿度翘曲应力衰减可忽略不计;针对地处高寒季冻区的连续配筋混凝土路面,需重视盐冻损伤导致的湿润区间加剧引发的钢筋锈蚀问题,常规混凝土路面则需着重考虑盐冻对力学性能的影响。

This paper intends to explore the correlation between capillary water absorption coefficient of pavement concrete and salt-thaw damage degree in pavement.The study conducts a salt-frozen test in room by capillary water absorption test and mechanical test on frozen concrete,and analysing the pavement performance index control of cement pavement in service period in cold region.The results show that there is a tight nonlinear relationship between capillary water absorption coefficient and freeze-thaw times and damage degree.The influence depth of external wetting states on pavement concrete increases continuously with the increase of the number of sat-freezing,and along with the damage degree D to 0.13,the influence depth expands by 20%.Compared with the loss of bending strength,the attenuation of humidity warpage stress of pavement concrete caused by salt-freeze damage can be ignored.For CRCP located in cold regions,the aggressive corrosion caused by by salt-freezing damag in wet zone should be paid attention to,while for CCP,the influence of salt-freezing on mechanical properties should be considered seriously.