Spalling Concrete Repairs and Waterproofing Works to External Façade Ledges at International Plaza

International Plaza is a high-rise 50- storey  commercial  and  residential within  the  Downtown  Core  of Singapore. The external architectural feature of the building is essentially reinforced concrete ledges, also used to house aircon compressor units.

As a result of aging concrete, and exposure to weathering, the steel reinforcements within have corroded leading to spalling concrete. Several other contractors have attempted to rectify the spalled concrete, but to no avail.

Furthermore, the situation became serious  when  chunks  of  spalled concrete fell off, endangering public.

Fibrwrap Construction Pte Ltd was invited by the Client to submit a competitive bid along with several other contractors. The contract was awarded to Fibrwrap Construction after the Client’s Consultants evaluated all bids based on the premise of Fibrwrap Construction’s offer being the most superior in terms of technical aspects, materials proposed, construction technology and efficient sequencing on top of being cost competitive.

The ledges were first tapped to check for hollowness, spalled concrete were demarcated and hacked exposing reinforcement bars till sound concrete is reached. Lost steel sections from corroded steel beyond acceptable limit were replaced, before the polymer modified cementitious mortar was used to fill up the hacked concrete area to the required level.

For longevity and prevention of further corrosion of steel and hence, spalling concrete, the TYFO^® Fibrwrap^® Composite System was applied onto the surface of the ledges. All in, the entire four faces of the 50-storey building was repaired ahead of schedule by two months.