Study On Key Technologies Of No.5303A Project Of Shenzhen Metro Line5

With domestic cities and towns progress faster and faster, underground develop quickly, and at the same time many technical problems concerning metro construction will also come forth. In this paper key technologies of No.5303A project of Shenzhen Metro Line5are studied, the main work of the paper are as follows:(1) In the construction process by core tube deep-hole grouting method in water-rich valley backfilled soil and weathered granite regions, construction technology of traditional mining method were improved and optimized, which not only ensure the tunnel passed through complicated water-rich regions successfully, but also controlled ground surface settlement, ensured construction safety and met schedule requirements.(2) Strengthening technology by deep-hole grouting method combined with surface grouting method of CD construction method in the construction of shallow bias tunnel in sandy cobble bed, difficult problems were solved when the tunnel under crossing high slope, the results shows that the construction safety was ensured and the schedule requirements was met.(3) Because of big terrain undulation in weathered granite regions, part of underground retaining wall could not be built, suspended retaining wall were built which ensure the safety of deep foundation pit enclosure structure.(4) Because of high-voltage power lines could not be moved, so the enclosure structure could not be closed. The comprehensive technology of additional pile were designed at the back of underground retaining wall, deep-hole grouting, dewatering outside and lattice girder reinforced shotcrete support, the results shows that the safety of deep foundation pit enclosure structure and power lines were ensured.A series of key technologies and difficult problems were solved in this paper, research has been applied in the existing project successfully, experience were accumulated and provided to similar engineering.