Construction organization design of an overpass project in Chengdu
The project is located at the intersection of xx Road and xx Avenue, The west side of xx bridge is about 1km away from the third ring road overpass of xx road, which is the main north-south traffic artery of the city. The tunnel under the overpass is designed as a two-way four lane tunnel. The tunnel frame length is 70m, the length of the approach channel is 388.84m, the design fullness of sewage main pipe is 0.7, the fullness of rainwater main pipe is 1.0, the width of the red line of Hongxing Road is 40m, and the red line within the scope of the overpass is widened locally, Design load of tunnel main body: urban level A; Cross slope of tunnel pavement: 1.5%; Seismic intensity 7; Design speed: 60km/h in the tunnel, drainage system adopts sewage and rain water fluid system, the tunnel longitudinal section adopts "V" slope, the maximum longitudinal slope is 4.9%, the minimum vertical curve radius is 1800m, the average cover depth of roof is 1.6m, all frames are made of C30 concrete, impermeability grade is S8, double box integral frame, the overall height of the frame is 7.27m, and the internal net height is 5.0m.