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 Transport

11 May 2026

Shivraj Chouhan Launches PMGSY IV and Announces Package for Madhya Pradesh

Union Minister Shivraj Singh Chouhan launched the Pradhan Mantri Gram Sadak Yojana (PMGSY) IV at Bhairunda in Sehore district during the 25 year celebrations and announced a development package for Madhya Pradesh. The programme was organised by the Union Ministry of Rural Development and attended by Chief Minister Dr Mohan Yadav, ministers of state, state ministers, legislators and senior officials from the centre and the state. The minister said the central government under the Prime Minister is committed to strengthening rural livelihoods through improved connectivity, housing and women's in..

DMR Engineering Reports FY 25-26 Financial Results

DMR Engineering reported its half year results for the financial year ended 31 March 2026 and published full year figures on a standalone basis. Standalone revenue from operations decreased by 2.01 per cent year-over-year to Rs 102.58 million (mn), while profit after tax declined by 43.94 per cent to nine point five six mn, leaving a profit after tax margin of nine point zero five per cent. Earnings per share stood at Rs zero point nine two, a fall of 44.71 per cent year-over-year. The company attributed part of the decline to one-off provisioning for bad debts and additional financing charges..

Atlanta Electricals Posts Strong FY26 Growth And Debt Free Finish

Atlanta Electricals reported audited consolidated results for the quarter and year ended 31 March 2026. The company recorded significant year-on-year revenue growth driven by capacity ramp-up at new facilities and higher utilisation at legacy plants. The announcement summarised operating improvements and strategic milestones achieved during the year. For Q4 the company reported revenue of Rs 7.48 bn and for FY26 revenue of Rs 18.52 bn, representing robust growth versus the prior year. EBITDA in Q4 was Rs. 1.49 bn and Rs. 3.44 bn for the full year, with margins expanding to 20 per cent in the q..