滑动式防护棚在上跨铁路既有线施工中的应用

为减少上跨铁路施工对铁路行车的干扰，搭设跨铁路防护棚已成为保证行车安全的重要手段之一。淮息高速公路跨京九铁路分离式立交桥跨铁路架梁及桥面系施工前需要完成铁路防护棚施工，但棚顶距离箱梁底部净空小，主体工程施工完毕后，后期棚架拆除过程非常困难，故采用新型滑动式防护棚。跨铁路施工时，滑移防护棚至相应位置后进行施工，工程完工后，将防护棚滑移出桥位，进行拆除。对新型滑动式防护棚的构造及施工技术进行了阐述。与传统的固定式防护棚架相比，滑动式防护棚在施工工期、成本控制、安全保证等方面具有一定的优势，可在上跨铁路施工中推广应用。

The Application of the Sliding-Type Protective Shed to the Construction of a New Expressway Spanning the Existing Railway

In order to reduce the affection of the existing-railway-spanning construction on the normal operation of the existing railway, the provision of the railway-spanning protective shed becomes one of the important means to ensure the safe operation of the existing railway. With the Huaixi Expressway overpassing the Beijing-Kowloon Railway, the girder-erecting construction of a separation flyover overpassing the existing railway is involved,and the construction of the railway-protecting shed has to be performed before the beginning of the construction of the deck system. However,owing to the clearance between the top of the shed and the bottom of the box girder being very small,it would be very difficult to remove the shed after the main body of the as flyover is finished. Therefore, a new-type sliding protective shed is adopted for the construction. When the railway--overpassing construction is going to be performed, the sliding-type protective shed is first moved to the appropriate position before the con- struction begins. When the project is completed, the sliding-type protective shed will be removed away from the bridge and disas- sembled. The composition of the new-type sliding protective shed and the construction techniques for the shed are dealt with in the pa- per. Compared with the conventional fixed guard scaffolding, the sliding protective shed, having certain advantages in the construction duration, cost control and security guarantee, may be popularized in the construction of other railways-spanning proiects.