As the population of Hong Kong continues to grow, its Mass Transit Railway operator (MTR) continues to enhance its existing railway network. In 2016, MTR undertook an extension of the Kwun Tong line to Whampoa. In 2017, waterproofing challenges were discovered at the new Whampoa station when
the contractor found leaks. There was a very high hydrostatic pressure as the station and tunnels were dug 16 meters below grade. An additional challenge was that construction crews were only allowed to work between 2:00 am and 4:00 am to avoid disturbing residents in the area. The General Contractor considered using epoxy injections to repair leaks but decided this was not a permanent solution.
The project team opted for Kryton’s Krystol Leak Repair system knowing it can be applied to the negative side of hydrostatic pressure (inside the tunnel) and provides a permanent waterproof solution. The leaks in the tunnel were stopped by first using fast setting, Krystol Plug before applying Krystol Repair Grout. Krystol Internal Membrane (KIM) treated concrete and Krystol Bari Cote were used to repair honeycombs in the concrete, before the concrete surface of the tunnel was waterproofed using Krystol T1 and T2 surface applied waterproofing system. Krystol T1 & T2, Krystol Bari-Cote, KIM and the Krystol Repair Grout all contain Krystol technology. When added to concrete, Krystol chemically reacts with water and un-hydrated cement particles to form insoluble needleshaped
crystals that fill capillary pores and micro-cracks in the concrete and block the pathways for water and waterborne contaminants. The project team found that by choosing Kryton solutions, they saved considerable time on the repair and reduced short-term costs. The tunnel is now permanently waterproof and the Kryton products are also providing long term durability.
Krystol Internal Membrane (KIM) is a hydrophilic crystalline admixture used to create permanently waterproof concrete.
Krystol Bari-Cote is a high-strength crystalline concrete waterproofing top coat used to resurface and repair concrete or masonry.
As part of the Krystol Leak Repair System, Krystol Repair Grout is a crystalline concrete waterproofing product that stops the flow of water to permanently repair leaking cracks, holes and joints in concrete, and can also be used to resurface and waterproof defective, damaged or deteriorating concrete. The grout employs advanced fiber technology and shrinkage controlling additives to prevent cracking.