Controlled demolition of a 250m chimney in SiberiaPublished 15/9, 2017 at 12:59
At the end of 2016, Tyrolean abrasives manufacturer Tyrolit worked with its customer Aktivmontage in St. Petersburg, Russia, to reduce a 250m tall chimney of a hydroelectric power station in Sayansk, Siberia down to a height of 150m. The chimney was near a residential area and controlled dismantling was the only option.
Aktivmontage, with its experience of using Tyrolit equipment, faced several challenges, including gaining access at height, working in tight conditions, and cutting through 200mm to 500mm thick reinforced concrete. The condition of the chimney meant that it was not possible to use wall saws. The working height inside the chimney also made the project special, due to the need to guarantee the safety of the workers and machinery at all times.
Working in Siberian winter the operatives encountered temperatures down to -25° Celsius, and needed to ensure the water supply for the machinery and tool did not freeze. Equally challenging was securing the individual concrete blocks, each weighing around 2t, for removal and lowering to the ground using cables.
Aktivmontage called Tyrolit who recommended the hydraulic wire saw system SK-SD and the diamond wire DWM***-C with a diameter of 10.2mm and 46 beads/m for concrete. The system is easy to dismantle for moving and transferring to a height of 250m and is compact and lightweight.
The Aktivmontage team spent over two months preparing for construction of the steel scaffold inside the chimney and commissioning the integrated lift. The plan was to remove the chimney block by block from the top down. The chimney wall got thicker towards the bottom, so blocks of concrete up to 500mm thick had to be cut through. The robust and compact Tyrolit wire saw system SK-SD was easy to handle in a very confined space and had to be moved and repositioned around 150 times for each block 100m up the chimney.
The individual concrete blocks, each weighing 2t, were removed level by level and lowered to the ground using a cable on the outside of the chimney. Around 800m of diamond wire were used on the project. Tyrolit was also prepared for on-site emergencies and stored all necessary spare parts in a nearby warehouse in case of repairs.