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水泥混凝土路面板的温湿度翘曲和交通荷载的耦合作用是其发生疲劳破坏的主要原因之一。湿度梯度及湿度翘曲在路面板中的存在时间较为持续长久,不可避免地会受到混凝土徐变的影响。该文进行了干燥和密闭状态下水泥混凝土梁的弯曲徐变试验,提出弯曲徐变度和徐变系数的计算方法,并将上述徐变参数植入有限元程序中模拟分析徐变对结合式和分离式混凝土路面板翘曲变形和应力发展影响。结果表明:干燥状态下的弯曲徐变是密闭状态下徐变的1.67倍;徐变能够降低翘曲变形、翘曲应力及与荷载耦合情况下的总应力;徐变对结合式路面板的翘曲变形和应力发展影响较大,徐变降低了36%的湿度翘曲变形和45%的翘曲应力;在板角交通荷载的耦合作用下,徐变可使结合式路面板的总应力降低34%。因此徐变是合理分析混凝土路面板的翘曲变形和应力发展不可忽略的因素。
Cement concrete pavement temperature and humidity warheads and the coupling of traffic load is one of the main causes of fatigue failure. Humidity gradient and humidity warp exist in pavement slab for a long time, will inevitably be affected by concrete creep. In this paper, the bending and creep tests of cement concrete beams under dry and closed conditions were carried out. The calculating methods of bending creep and creep coefficient were put forward. The creep parameters were implanted into the finite element program to simulate the creep and creep tests. And separate concrete pavement warp deformation and stress development. The results show that the creep deformation under dry condition is 1.67 times that of the creep condition under confined condition. The creep deformation can reduce the warpage, warpage stress and total stress under coupling with load. Curvilinear deformation and stress development have a great influence on creep deformation, which reduces the warpage deformation by 36% and warpage stress by 45%. Under the coupling action of plate angle traffic load, creep can reduce the total stress of the combined pavement slab 34%. Therefore, creep is a reasonable analysis of concrete pavement warp deformation and stress development can not be ignored factors.