摘要
为了揭示桥面铺装动态荷载下的力学响应规律,以成都某高架混凝土桥沥青铺装工程为依托,以BRT公交车进站制动情况为荷载背景,采用数值模拟分析方法,结合正交试验数值分析结果,进行了桥面铺装方案的结构优化比选.以正交试验得出的优选方案为对象,进一步分析了车辆移动速度对BRT停靠站刹车减速段桥面铺装体系的受力影响,解释了其作用机理.研究表明:振动冲击与作用时间的综合作用导致铺装层竖向变形和剪应力响应存在"临界速度"的现象;不同初始车速下,各轴轮印处面层弯拉应力及剪应力存在短时快变的正负应力交互作用;在制动荷载作用下,表层剪应力较大,并在初始速度60 km/h制动工况下达到极值;在靠近公交站台等车辆制动或加速相对频繁的路段,应特别注意提高铺装层的抗剪切及抗疲劳能力,同时加强层间粘结.
To reveal the mechanical response characteristics of deck pavement under dynamic loads, taking for example the asphalt pavement of one viaduct in Chengdu, several asphalt pavement structures under the braking force of BRT buses were compared and analyzed by using the numerical simulation analysis methods and numerical analysis of orthogonal test. The selected pavement structure was taken as the further object, and the effects of moving vehicle speeds on the mechanical response of deck pavement on the braking deceleration section near the BRT bus stop were analyzed and its mechanism was also explained. The analysis shows that the vibration impact and loading period lead to the occurrence of critical speeds in surface vertical deflection and shear stress responses of the pavement. At different initial bus velocities, there is a short but fast-changing interaction of both positive and negative bending and shear stresses at each tire footprint area on pavement, in the surface layer. Under the braking loads, surface shear stresses were rather great, which arrived at a peak at an initial vehicle speed of 60 km/h. Near the bus stations where bus deceleration or acceleration occur frequently, anti-shearing and anti-fatigue performance of pavement structure should be improved and interlaminar bonding should be strengthened.
出处
《西南交通大学学报》
EI
CSCD
北大核心
2017年第4期685-693,共9页
Journal of Southwest Jiaotong University
基金
国家自然科学基金资助项目(51378438)
成都市交通科技资助项目(JHFDD-JSFW-001)
