Ulu Jelai Hydropower Dam

The main structures comprises:

• 90 metres high RCC dam
• Un-gated Spillway
• Bottom outlet and hydro-mechanical accessories
• Power intake tower;
• Power water-way underground
• Concrete lined surge shaft and surge tank
• Underground powerhouse
• Transformer chamber cavern
• Surge chamber cavern
• Water transfer tunnels (16 kilometres, excavated by TBM)
• Tunnelling works (Headrace Tunnel, Tailrace Tunnel, Main Access Tunnel and Service Tunnels Approx. 10 km in total)
  
• Switchyard
• Generation Control Building
• Access Road
  

The design of the RCC mixes took quite long time to define the proper mix for upstream RCC, downstream RCC, upper dam and lower dam ranging from high to low cementitious solutions with long setting times to ensure the bonding of the RCC layers. Plastiment® TM-21 retarder for RCC found an extensive use for RCC production.

More than 30 km of underground structures require a massive use of shotcrete technologies with alkali free shotcrete accelerators steel fibers reinforced even with site batching plant the complex internal logistic required long open time for the base concrete mixes.

Sigunit® L-53 AF MY was adopeted as best performing solution for shotcrete accelerator while Sika® ViscoCrete® SC 315 MY was able to ensure a 3 hours open time for shotcrete base mixes.