城市轨道交通地下线振动环境影响分析

采用城市轨道交通环境影响评价中的振动预测方法,通过北京、上海、广州10条运营线路的环保验收调查报告和轨道减振性能测试评估报告提供的实测数据和预测结果进行对比分析,结果表明:在一定的车速、埋深及区段等工程条件下,若按交通干线两侧昼、夜间振动限值标准进行评价,地下线的环境振动影响范围约20 m。地下线的振动影响主要取决于线路的线型、埋深,尤其与敏感点的距离、运行速度关系较大。地铁隧道上方5 m以内的建筑,环境振动无明显变化;5～20 m振动级衰减比较明显。正线区间比车场线及出、入段线敏感点的振动级高4～6 dB;出段线比入段线敏感点的振动级高2 dB左右。建议根据振动影响范围,做好轨道交通及其沿线用地规划。地下线路应合理选线,尤其要避免下穿环境敏感建筑;沿线规划控制应预留振动防护距离,在防护范围内不宜新建敏感建筑;对特殊敏感区段,可以考虑在夜间时段采取限速的措施。

Analysis on Underground Vibration Environment of Urban Rail Transit

By means of the vibration prediction method for urban rail transit vibration environment assessment,comparative analysis was carried out according to the measured data and prediction results obtained from Beijing,Shanghai,Guangzhou 10 metro lines’ acceptance reports on enviromental protection during operation and test and evaluation reports on track damping performance,results indicated: under the conditions of certain vehicle speeds,overburdens and the same section etc.,the affected distance by underground traffic was about 20m as evaluated according to the vibration limit standards along two sides of main traffic lines round the clock.Underground vehicle vibration depends on buried depth and types of lines,especially on distance to sensitive points and vehicle running speeds.For buildings located 5m and more above the railway tunnel the vibration effect does not change obviously,but for those located 5-20 m above the tunnel vibration damping is obvious.Vibrations on sensitive points along main lines are 4～6 dB larger than those along the vehicle yard lines and the entrance and exit lines.It is recommended to rationally design the route of lines to bypass sensitive buildings and plan the land use along urban railways.