纵形轨枕施工难点及改进措施

北京地铁6号线采用纵形轨枕,对套管预埋位置精度要求高。传统的套管固定采用螺杆或铆钉固定方式,工作量大且精度无法保证,为此采用定位销固定。定位销下端为螺杆、上部是伸缩性好的橡胶,既保证连接刚度、又使操作简单易行。同时对预制模型由固定方式改为滑动,改进了振捣技术,整体对施工工艺进行了优化。这些改进措施既保证了纵形轨枕产品质量要求,又满足了生产周期及工期要求,为该工艺推广使用提供借鉴。

Difficulties in and Improvement on the Construction of Longitudinal Sleepers

Line 6 of the Beijing Subway using longitudinal sleepers,the precision of the positioning of the casing embedded is highly demanding.The traditional casing used to be fixed with screws or rivets,in which case the workload was very high and the accuracy could not be ensured.Nowadays the casing is fixed with the positioning pin,the lower part of which is a screw,the upper part of which is made of elastically good rubber,and which can not only ensure the connective stiffness but also facilitate the operation and construction.Meanwhile the precasting model is changed from the fixed type to the sliding type,with the vibration technology much improved.The whole construction process is technically optimized.These measures not only help ensure the requirements in the product quality of longitudinal sleepers but also meet the requirements in the production cycle and the construction duration.The paper may serve as a useful reference for popularizing the process.