RETAINING WALL AND CONCRETE LINING TUNNEL DESIGN OF CILIWUNG RIVER – CIPINANG RIVER FLOODWAY

• Main Author: Pangihutan, Ronaldo
• Format: Final Project
• Language: Indonesia
• Subjects: Teknik sipil
• Online Access: https://digilib.itb.ac.id/gdl/view/64068
• Institution: Institut Teknologi Bandung

The city of Jakarta is an area that often experiences floods. One area that often experiences flooding is the area around the Ciliwung River. One alternative to overcome the flood problem in the Ciliwung River area is the design of a tunnel to drain excess water to the East Flood Canal (BKT) via the Cipinang River which is not accommodated by the Ciliwung River. The focus in this final project is the design of the geotechnical field, namely retaining walls as a barrier to lateral soil collapse due to soil excavation and tunnel linings as water distribution from the inlet weir to the outlet weir. Based on soil and field conditions, the retaining wall used is secant pile with strut reinforcement. Soil excavation is planned for 15 m with excavation stages carried out every 3 m. For the inlet weir, the secant pile is designed with a length of 54 m using strut reinforcement with a thickness of 1 m and 0.5 m. For the outlet weir, the secant pile is designed with a length of 50 m using strut reinforcement with a thickness of 1.5 m. Retaining wall modeling during construction was carried out under two conditions, namely undrained condition and drained condition, while long-term modeling was carried out for permanent service, permanent flood, and permanent earthquake. Analysis of retaining walls using the Plaxis 2D application with results in the form of shear forces, moment forces, retaining wall deflections, and safety factor for each excavation stage and long-term conditions. Reinforcement requirements for inlet and outlet structures are 60D32 for flexural reinforcement and D16-50 for shear reinforcement, while for the arriving shaft, 40D29 flexural reinforcement and D16-75 shear reinforcement are required. The tunnel channel lining design is carried out by reviewing the permanent static and permanent conditions of the earthquake. The thickness of the tunnel lining is 0.3 m and 0.35 m (for BH-10 soil data). Reinforcement requirements for channel lining are D25-130 for main reinforcement, D16-450 for shear reinforcement, and D10-150 for longitudinal reinforcement (for soil data BH-10 used D25-180 for main reinforcement and D10- 150 for longitudinal reinforcement).