加载速率对路面混凝土抗弯拉特性影响的试验与应用研究

Experimental and applying study on the influence of loading rate on flexural properties of pavemeent concrete

车辆荷载是明显的动态荷载,不同车速情况下车辆对路面混凝土施加的荷载特性与作用速率不同,而弯拉强度是水泥混凝土路面的设计控制指标,为了探讨加载速率对路面混凝土弯拉特性的影响规律,对C40混凝土小梁试件进行了不同加载速率下的三分点弯拉试验,分析了加载速率对路面混凝土弯抗强度及弯拉弹性模量等弯拉力学指标的影响规律,根据试验结果建立了混凝土弯拉强度与加载速率的相关公式,并且对试验结果进行了应用分析。有利于明确水泥混凝土路面在车辆荷载作用下的实际受力机理、优化水泥混凝土路面设计。

Vehicle load is obvious dynamic load.The load characteristics and load rates applying on the pavement concrete of different speed vehicles are different.Concrete flexural strength is the control index in cement concrete pavement design.In order to investigate the influence of loading rate on flexural properties of pavement concrete,three-point flexural tests of little concrete beam specimens（C40） are carried out under different flexural strain rates.Influence of loading rate on the flexural properties of concrete,which include flexural strength and flexural,are analyzed.The correlation formula between flexural strength and flexural strain rate was established according to the test results.And the test results was taken into the pavement damage analysis.These achievements can provide us with a more accu-rate grasp of actual bearing mechanism of pavement concrete under vehicle load and contribute to optimize the cement concrete pave-ment design.