Construction Scheme of Shanghai Small Sluice (Gravity Type retaining wall )
Content Introduction 9. Gravity Retaining Wall Bulkhead 9.1 Gravity Retaining Wall Bulkhead A1 adopts gravity masonry retaining wall Bulkhead Gravity Retaining Wall Structure A1: A1 type retaining wall is composed of bottom plate, mortar masonry wall body and coping, and the bottom plate and coping adopt cast-in-place C25 reinforced concrete structure. The upper width of the retaining wall is 0.50m, the bottom elevation of the bottom plate is 0.9m, the bottom width is 2.3m, and the thickness is 0.3m. In order to lower the underground water level behind the wall and reduce the residual water pressure, drainage holes and inverted filtering facilities are set at the L corner. The top elevation of the revetment wall is 3.7m, and the slope type soil slope is adopted below the elevation of 1.5m, and the slope is 1:2.5; A 0.75 m wide platform is set at an elevation of 1.5 m. The space between deformation joints is 10m, and the joints are filled with foam plastic plates. The front line of the structure revetment is 7.5m away from the bottom line of the channel, see the design drawings. The foundation trench excavation (drainage), cast-in-situ concrete cushion, cast-in-situ concrete bottom plate, mortar masonry wall body and coping, inverted filter layer setting, foundation trench backfilling and compaction are carried out in sequence. Temporary cofferdams must be built in some sections. Open ditch drainage is adopted during construction. In case of local quicksand, well point precipitation shall be adopted. 9.1.1 According to the characteristics of the construction site of the project, the original ground elevation is about 4.0m. According to the requirements of the design drawings, the excavation surface elevation of the foundation pit is 0.8m (excluding the tooth sill). It is considered to carry out the operation twice. The first mechanical excavation and the second manual excavation. Excavator shall be used for earth excavation and dump truck shall be used for earth transportation. When the mechanical excavation reaches 30cm from the design elevation, the operation will be stopped, and the rest of the earthwork will be excavated and slope repaired manually.