高弹桥面铺装表面冰层破坏特性的断裂力学分析

提出以破冰率Rbreak作为桥面冰层破坏的定量评价指标,根据强度理论及能量法计算确定了高弹性桥面冰层破坏形式及破冰率大小,通过在冰层底部不同方向植入初始裂纹,采用断裂力学方法计算了裂纹扩展特征,首次提出了基于断裂力学方法的破冰率修正系数,得到主要结论:采用橡胶颗粒沥青混合料高弹桥面铺装层可实现桥面冰层破坏,且冰层破坏形式为受压破坏;由断裂力学方法计算得到的冰层底部裂纹扩展方式为滑开型开裂;提出以滑开型开裂对受压型破坏的破冰率修正系数为1.81.

Fracture mechanical analysis of ice failure characteristics of high elastic bridge pavement superficial ice layer

The ice-broken rate Rbreak is proposed as quantitative ice broken evaluation index of bridge pavement;failure mode and Rbreak value of high elastic bridge pavement is calculated according to strength theory and energy method.After initial crack was implanted along different directions at the bottom of ice layer,crack propagation characteristics are calculated and modification factor for Rbreak is proposed according to mechanics of fracture for the first time.Main conclusions are drawn as follows.It can achieve ice-broken by using rubber particles asphalt mixture high elastic bridge pavement,the ice failure form is compression failure.Propagation form of crack at the bottom of ice layer is sliding open type according to mechanics of fracture.The modification factor for Rbreak of sliding open cracking to compression type failure is 1.81.