Slipforms for hydropower projects

01 Jun 2019 CW Staff

HCC opted for slipforms for the concreting of a 115-m-deep surge shaft for the Punatsangchhu hydropower project Stage I, a 1,200-mw, run-of-the-river project in Western Bhutan.

“We opted for slip-forming because it enables continuous, non-interrupted, cast-in-place jointless concrete structures that have superior performance characteristics compared to piece-wise construction using discrete form elements,” says S D Jeur, Senior Vice-President, Projects, HCC.

Slipforms with a three-layered platform structure were used. The entire formwork structure was built in-house. The top platform was used to erect the reinforcement concrete, the middle platform was used for general movement, and the bottom one was used to provide the finishing to the concrete surface.

Slipforms have to be in a continuous motion so that the concrete does not stick to them. The speed of this formwork depends on several factors like the weather condition, the amount of concrete poured at a time and the size of the structure. As the slipform can move (slipping rate, usually between 5 and 30 cm/hour) whenever the concrete can carry the load of its weight in the lowest parts of form sheet, the likely concrete setting time was determined based on the weather conditions (temperature, humidity, etc), cement ratio, type of cement, slump and admixtures.

Usually, the slipform structure rises up with the daily progress of 0.75 m/day in standard conditions. However, at Punatsangchhu-I HEP, the daily progress harnessed from slipform was at an average of 1 m/day. The concrete lining thickness varied from 850 mm at the top, 1,200 mm in the middle and 1,500 mm at the bottom. Concrete was poured into the forms in layers of about 200 mm.

CHARU BAHRI

Infrastructure Urban

10 Mar 2026

ABB to Invest Rs 6.25 Billion to Expand India Manufacturing

ABB recently announced plans to invest approximately Rs 6.25 billion ($75 million) in India during 2026 to expand its manufacturing footprint and research and development capabilities. The investment follows more than $35 million spent in 2025 and reflects the company’s continued focus on strengthening its ‘local-for-local’ strategy in the country.The investment will support ABB’s Electrification, Motion and Automation businesses and expand manufacturing capacity for infrastructure sectors such as renewable energy, metro rail, data centres and industrial applications. Approximately 300..

Six WOLFF Cranes Handle 60,000 m³ Concrete for German Hospital

Six WOLFF tower cranes are playing a key role in constructing a new hospital complex in Memmingen, Germany, supporting large-scale material handling for the project. The facility is being built on a 7.7-hectare site and will feature six floors, around 480 beds and a gross floor area exceeding 75,000 sq m.Building shell works began recently in February 2025. One WOLFF 6531.12 Cross crane supported early site preparation before being dismantled in autumn 2025, while five remaining cranes continue operations. Over an average deployment period of 16 months, the cranes are expected to move approxim..

REC Funds Rs 115.6 Million CSR Support for Bihar Eye Hospital

REC recently committed Rs 115.6 million under its Corporate Social Responsibility (CSR) programme for the procurement of clinical and non-clinical equipment at Sankara Eye Hospital in Saharsa, Bihar. The initiative aims to strengthen healthcare infrastructure and improve access to specialised eye care services in the region.A Memorandum of Agreement (MoA) was recently signed between Pradeep Fellows, Executive Director (CSR), REC Limited, and Wg Cdr V. Shankar (Retd), Trustee and Executive Director of Sankara Eye Hospital, at the REC office in the SCOPE Complex, New Delhi.The support is expecte..