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

06 Apr 2026

InsideFPV Delivers ₹10 Crore Kamikaze Drone Order Under MoD’s EPR Route

InsideFPV, a Surat-based drone technology manufacturer, has successfully executed a ₹10 crore defence contract to supply indigenous kamikaze drones under the Ministry of Defence’s Emergency Procurement Route (EPR). The company completed the delivery of hundreds of FPV kamikaze drone platforms within a rapid two-month timeframe, highlighting its ability to meet urgent military procurement timelines.The supply orders were fulfilled under the emergency procurement mechanism, which is aimed at fast-tracking acquisitions for immediate operational needs. InsideFPV’s quick execution reflects it..

Vedanta Resources Secures Fitch Upgrade to ‘BB-’, Best Rating Since 2015

Vedanta Resources Limited (VRL), a global player in metals, oil & gas, critical minerals, power and technology, has received a credit rating upgrade from Fitch Ratings, marking its strongest bond rating in over a decade.Fitch has raised Vedanta Resources’ Long-Term Foreign-Currency Issuer Default Rating (IDR) to ‘BB-’ from ‘B+’, while maintaining a Stable Outlook. The agency also upgraded VRL’s senior unsecured rating, along with the ratings of US dollar-denominated bonds issued by Vedanta Resources Finance II Plc and guaranteed by VRL, to ‘BB-’.The upgrade represents Vedan..

NAREDCO NextGen NCR Chapter Launched

The NAREDCO NextGen NCR Chapter was recently launched at Excelerate 2026 in Mumbai, marking a key step towards integrating emerging real estate leaders from the National Capital Region with the national platform. The initiative aims to promote sustainable and responsible urban development through collaboration and knowledge exchange.The event brought together young developers, entrepreneurs, and professionals from across NCR, including Noida, Gurugram, Ghaziabad, Faridabad, Bhiwadi, and Meerut. Discussions focused on urban development, finance, sustainability, innovation, and policy, emphasisi..