桥头路桥不平顺引起的车桥振动研究

发布时间：2018-03-04 01:27

本文选题：路桥过渡段　切入点：差异沉降　出处：《湖南大学》2015年硕士论文　论文类型：学位论文

【摘要】：路桥过渡段普遍存在的差异沉降以及桥头经常破损的伸缩缝均可统称为桥头路桥不平顺,二者均会加剧过往车辆的振动,影响行驶安全,降低乘坐者舒适感,放大车辆对桥头的局部冲击作用,进而加速桥头伸缩缝,桥面板等构件的破损,形成恶性循环。研究表明,桥面板承受的跳车冲击荷载可能高达静荷载的5-6倍,而且在伸缩缝破损的影响下,桥面板设计应取决于伸缩缝附近的桥面板局部响应。因此,很有必要研究桥头路桥不平顺对桥面板的局部冲击作用,而目前鲜有学者关注此问题。桥梁设计规范采用基于桥梁整体响应(如跨中挠度)确定的冲击系数来衡量桥面板所受的局部冲击,而此冲击系数对控制内力为横向弯矩的桥面板可能并不适用。此外,国内外均尚未有统一的差异沉降控制标准。学者们主要通过调查行车舒适度提出各自的控制标准,缺乏全面地从人,车,桥三方面振动对差异沉降提出更合理的控制标准。对此,本研究建立了车—路—桥系统振动模型,首先研究了伸缩缝破损状态对桥面板的局部冲击系数(基于桥面板的横向弯矩计算)和桥梁整体的冲击系数(基于桥梁整体响应计算)的影响。结果表明伸缩缝的破损会造成局部冲击系数明显增大,而对整体冲击系数基本无影响。之后,研究了路桥过渡段差异沉降对人、车、桥三方面的影响,即对乘坐者舒适度,车辆行驶安全以及桥梁的冲击作用,包括桥面板的局部冲击系数和桥梁整体的冲击系数三种指标的影响。最后,参照规范对上述指标的建议值,提出了合理的差异沉降控制量。
[Abstract]:The common differential settlement in the transitional section of the road and bridge, as well as the often damaged expansion joint at the bridge head, can all be called the bridge road and bridge irregularity, both of which will aggravate the vibration of the passing vehicle, affect the driving safety and reduce the comfort of the rider. The local impact of vehicle on the bridge head is magnified, and then the damage of the bridge head expansion joint, bridge deck plate and other components is accelerated, which forms a vicious circle. The research shows that the impact load of the bridge deck board may be 5-6 times of the static load. Under the influence of expansion joint damage, the design of bridge deck should depend on the local response of the bridge deck near the expansion joint. Therefore, it is necessary to study the local impact of the bridge deck on the bridge deck caused by the bridge roadway irregularity. At present, few scholars pay attention to this problem. The bridge design code uses the impact coefficient based on the overall response of the bridge (such as mid-span deflection) to measure the local impact of the bridge deck. The impact coefficient may not be applicable to the bridge deck with lateral bending moment. In addition, there is no uniform standard for differential settlement control at home and abroad. Scholars mainly put forward their own control standards through investigation of driving comfort. In this paper, the vibration model of vehicle-road-bridge system is established, which is lack of a more reasonable control standard for differential settlement from three aspects of human, vehicle and bridge. Firstly, the influence of the damaged state of expansion joint on the local impact coefficient (based on the transverse moment calculation of the deck slab) and the overall impact coefficient of the bridge (based on the calculation of the bridge overall response) is studied. The results show that the expansion joint is affected by the calculation of the overall response of the bridge. The local impact coefficient will increase obviously due to the breakage. After that, the effects of differential settlement on human, vehicle and bridge are studied, that is, the comfort of the rider, the safety of the vehicle and the impact of the bridge. The influence of the local impact coefficient of bridge deck and the impact coefficient of the whole bridge is included. Finally, the reasonable differential settlement control amount is put forward with reference to the suggested values of the above indexes in the code.
【学位授予单位】：湖南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U441.3

【参考文献】