基于实车试验的大跨度桥梁轨道静态长波高低不平顺验收标准验证

Verification on Acceptance Standard for Track Static Long-wave Longitudinal Level Irregularity on Long-span Bridge Based on Real Train Test

由于温度、施工偏差、二期恒载等因素影响,高速铁路大跨度桥梁成桥线形与设计线形存在较大差异,且矢距差法不适用于大跨度桥梁和地基大面积沉降等区域的轨道线形验收。针对速度为250 km/h的高速铁路有砟轨道大跨度桥梁,基于轨道高低不平顺不同弦测值与车体垂向振动加速度之间的相关性,提出高低不平顺60 m弦测值与车体垂向振动加速度之间的关联关系,进而给出桥上轨道静态高低长波不平顺60 m中点弦测值10 mm的验收限值建议,最后在某主跨为672 m的高速铁路斜拉桥上预设“四峰三谷”形式的轨道高低不平顺并进行实车验证,证明此限值建议的合理性。结果表明:对于速度为250 km/h的高速铁路,车体垂向振动加速度与不平顺60 m弦测值之间呈线性关系;大跨度桥梁温度变形显著,整体表现为桥面高程与温度成反相关关系,但桥梁温度变形主要表现为长波不平顺;预设的60 m余弦波形式的轨道高低不平顺主要影响行车舒适性,对安全性影响较小,且列车速度在275 km/h及以下时,产生的车体垂向振动加速度最大值为0.98 m/s2,舒适性指标最大为2.47,评价为“优秀”,接近优秀/良好分界线。

As significant differences exist between the alignment of completed long-span bridge of high-speed railway and designed alignment of such a bridge in the acceptance stage due to the influence of temperature,construction deviation,secondary dead load,the vector distance difference method is not suitable for the acceptance of track alignment in long-span bridges and areas such as large-scale settlement of foundations.Aiming at the long-span bridge with ballasted track of high-speed railway with a speed of 250 km/h,the correlation between the chord measurements of 60 m of track geometric irregularity and the vertical vibration acceleration of car body was proposed based on the correlation between the different chord measurements of track geometric irregularity and the vertical vibration acceleration of car body.Furthermore,the acceptance limit of 10 mm for the mid-point chord of 60 m track static longitudinal level irregularity on the long-span bridge was proposed.Finally,a track longitudinal level irregularity in the form of“four wave peaks and three wave troughs”was preset on a high-speed railway cable-stayed bridge with a main span of 672 m,and verified by the real train,which proved the rationality of the proposed limit value.The results show that,for the high-speed railway with a speed of 250 km/h,the relationship between the vertical vibration acceleration of the car body and the 60 m chord measurement of track longitudinal level irregularity conforms is linear.The temperature deformation of long-span bridges,as mainly manifested as long wave irregularity,is significant,with an overall inverse correlation between bridge deck elevation and temperature.The preset track longitudinal level irregularity in the form of 60 m cosine wave mainly affects the ride comfort,with minor impact on the running safety.In addition,at the train speed of 275 km/h or below,the maximum vertical vibration acceleration of the car body is 0.98 m/s 2,with the maximum Sperling index of 2.47,which is evaluated as“excellent”and close to the boundary between“excellent”and“good”.