混凝土路面板早期开裂疲劳寿命预测

Fatigue life predictions of concrete pavement with premature cracking

为准确预测水泥混凝土路面板在早期裂缝情况下的疲劳寿命,帮助制定合理的维修计划、延长道路使用寿命,该文通过小梁四点弯拉及混凝土板疲劳加载试验,研究了混凝土断裂力学参数及疲劳行为,并对有裂缝混凝土板的疲劳寿命进行预测分析。试验研究和模型预测均表明:混凝土路面板早期开裂疲劳寿命或破损过程分为3个阶段,且板的疲劳断裂寿命远小于传统模型预测值;开放交通时间的早晚对板的疲劳寿命有至关重要影响。研究结果对于准确预测疲劳寿命和及时进行路面维修与裂缝处理具有实际意义。

Premature transverse cracking can occur in concrete pavement subject to repetitive truck loading. This premature cracking may cause final failure of the pavement and greatly reduce the service life.This study investigates the fracture properties of notched concrete beams to establish a fatigue life prediction model.Both the model and the experimental tests show that the pavement fatigue life is greatly reduced compared to traditional models if a partial depth crack develops within the first few days after placement.Thus,the opening time to traffic is crucial for the pavement fatigue life.The findings are of significance for proper schedule maintenance plans.