中文摘要：

在分析双块式轨道轨枕松动病害的成因及发展过程的基础上,运用车辆—轨道垂向耦合动力学理论,建立含轨枕松动病害的车辆—双块式无砟轨道—下部基础垂向耦合振动有限元简化计算模型,结合现场测试,研究列车运行速度、轨枕空吊高度及轨枕松动数量对轨道结构动力响应及车辆运行平稳性和安全性的影响.研究表明：双块式无砟轨道轨枕松动对轮轨系统动力响应影响较大,轮轨系统动力响应随轨枕松动数量、空吊高度和行车速度的增大而增大;当轨枕空吊小于0.5mm以下时,轨枕松动对轨道结构和行车影响较小;轨枕松动病害发展到2根及以上时,轮轨系统动力响应明显增大;轨枕松动病害直接影响轮轨接触性能,影响行车的平稳性和安全性,对于高速铁路线路,一旦发现轨枕松动,应及时修复.

英文摘要：

Based on the analysis of the cause and development for the sleeper looseness of bi-block slab track, using vehicle-track vertical coupling dynamics, a finite element model which included the sleeper looseness was established for the vertical coupling vibration of vehicle, hi-block slab track and infrastructure. Combining with field tests, the influence of vehicle traveling speed, the height of sleeper hanging and the number of loose sleepers on the dynamic response of track structure, vehicle ride comfort and safety were analyzed. The results show that, the sleeper looseness of bi-block slab track has greater impact on the dynamic response of wheel-track system which increases with the number of loose sleepers, the height of sleeper hanging and vehicle traveling speed. There is little impact on the track structure and traffic safety when the height of sleeper hanging is less than 0. 5 mm. The dynamic response of wheel-track system increases obviously when the number of sleeper looseness is up to two and above. Sleeper looseness directly affects the performance of wheel-rail contact as well as the ride comfort and safety. Therefore, for high speed railway, the sleeper looseness should be repaired in time once it is found.