摘要
计算和分析正交异性钢桥面铺装层表面裂缝应力强度因子,在此基础上应用Paris扩展公式预测铺装层疲劳寿命。将奇异单元布置在铺装层表面裂缝前沿,建立正交异性钢桥面系三维断裂力学有限元模型,计算铺装层表面裂缝的应力强度因子;分析裂缝应力强度因子随轴载作用位置的变化规律,确定了带裂缝铺装层轴载作用的最不利荷位;以最不利荷位作为轴载作用的标准荷位,计算应力强度因子随裂缝扩展深度的变化,并数值拟合得到了应力强度因子与裂缝深度的关系式;将应力强度因子的深度关系式代入Paris公式,积分得到铺装层的疲劳寿命。计算结果表明,基于钢桥面铺装层带裂缝工作的事实,应用断裂力学方法预测钢桥面铺装层疲劳寿命是可行的。
The stress intensity factor （SIF） for the surface crack of the pavement on orthotropic steel bridge decks is calculated and analyzed. The Paris＇formula is employed to forecast the fatigue life of the pavement. A three-dimensional fracture-mechanics finite element model of orthotropic steel bridge deck systems is developed. According to the change in the SIF with the change in the loading position of the axle-load, the worst loading position of the axle-load on the cracking pavement of the steel bridge deck is determined, the change in the SIF with the change in the crack depth is analyzed, and the relationship between the SIF and the crack depth is established. The expression of the SIF is substituted into the Paris＇formula, and the fatigue life of the pavement is calculated by using an integral of the Paris＇formula. The result indicates that fracture mechanics can be employed to forecast the fatigue life of the pavement on orthotropic steel bridge decks.
出处
《土木工程学报》
EI
CSCD
北大核心
2006年第9期112-116,122,共6页
China Civil Engineering Journal
基金
国家自然科学基金项目(50578038)
教育部博士点基金项目(20050286008)
关键词
正交异性钢桥面板
钢桥面铺装
断裂力学
应力强度因子
Paris公式
疲劳寿命
orthotropic steel bridge deck
paving of steel bridge deck
fracture mechanics
stress intensity factor
Paris＇ formula
fatigue life
