Promat's Promatect®-H boards are being used to line a 1.4 km underwater tunnel on Palm Jumeirah development in Dubai, the extraordinary man-made island off the coast. Promatect®-H, a non-combustible calcium silicate board, is being used to line the tunnel connecting the Crescent of the development to the main palm trunk. Tunnel fires can reach temperatures of up to 1,200°C within minutes, which can destroy the structural stability of concrete and create spalling, that is chunks of concrete flying off amid the heat.
Passive fire protection is built into the fabric of a structure. It creates a physical barrier to contain heat and prevent the spread of smoke and fire. It can't be turned off and requires no power or water to work. Promat's products and systems help control the course of a fire and the damage it can do. They can hold back fires for up to 240 minutes, giving occupants time to escape and firefighters a chance to save the structure.
The project's developer, Nakheel, was looking for fire protection boards that met what it considers to be the highest and safest standards. This was the Dutch Ministry of Transport procedure, a protocol also approved by the UK's Building Research Establishment. The Promatect®-H boards met these performance requirements.
The main contractor Taisei ordered the boards with a schedule of required deliveries to meet their construction programme. The boards were received on or before the required dates. They were well-packed and protected. The Promatect®-H boards were supplied accurately cut and finished. Taisei set up a dedicated workshop on site to prepare the boards prior to installation. Promat sent two engineers to site during the first few days to give advice to Taisei�s installation team and help with design and installation techniques. The boards are easy to handle and place, as shown by the improved production and installation rate. Two installation techniques were used on the Palm Jumeirah development's tunnel. For the ceiling, the team went with a so-called lost formwork method. Here the boards were laid on the load-bearing formwork with the smooth face down to provide a fair faced finish on completion.
The boards were pre-cut and were installed using straight joints. After the first layer of reinforcement had been installed, 50 mm stainless steel screws were inserted to a depth of 20 mm. The remaining 30 mm stuck out of the board, creating the anchorage for the concrete. After the concrete was sufficiently cured, the formwork was removed.
One of the products of Promat's on-site support was an installation technique devised for the curved section of the tunnel. Each set of boards was placed on plywood in the on-site workshop and cut in one go. This minimized the gap between the boards.
On the walls of the tunnel, the Promatect® panels were installed after the walls had been built. The panels were butt-jointed next to each other, and hung on the concrete walls with stainless steel anchors.
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