镐头机拆除刚性道面动力损伤分析

摘要

In order to determine the technical parameters for airport rigid pavement demolition reasonably,a finite element model of rigid pavement was established using the ABAQUS software,and a half-sine impact load was imposed on the rigid pavement to analyze its dynamic responses under pickaxe machine breaking load. The dynamic responses including vertical displacement and tensile stress were calculated by systematically considering load parameters and pavement structure parameters. The simulation results show that the magnitude and position of load have a significant influence on the dynamic responses of rigid pavement. The thickness of slab has a great influence on the tensile stress and little effect on the vertical displacement. Under the example condition,the dynamic responses become prominent only when joint load transfer capacity is below 80%. The location of impact load should not be within 30 cm away from the edge of slab so as to mitigate the dynamic damage of reserved slab.%为合理确定刚性道面的拆除工艺参数，采用ABAQUS软件，建立了刚性道面的实体有限元模型，对镐头机钎杆半正弦波冲击荷载作用初期刚性道面的动态响应进行了模拟，系统分析了镐头机荷载参数和道面结构参数对刚性道面竖向位移和板底拉应力响应的影响规律。模拟结果表明：镐头机冲击荷载的大小及其作用位置对刚性道面动态响应有显著影响；板底最大拉应力受面层厚度影响较大，而道面竖向位移对面层厚度变化不敏感。在算例条件下，当接缝传荷能力小于80％时，结构动态响应才发生显著变化；为减小对保留板的动力损伤，拆除板板边30 cm范围内不宜使用镐头机拆除。