Advanced Technology & Materials


Concrete spalling is usually one of the biggest issues when it comes to ageing buildings. However, proper maintenance is always long overdue, noisy, and costly. In view of this, Chun Wo has worked on one of our major innovation projects, Rapid Repair Mortar Material (R²M²), a safer and faster solution for repairing concrete spalling.

Rapid Repair Mortar Material (R²M²)

Rapid Repairing Mortar Material (R²M²) is a stainless-steel fiber reinforced mortar which has strong tensile load resistance when compared to conventional repair mortars. Its intended use in repairing RC slabs with spalling concrete and corroded rebars would save time (i.e., reduced opening-up of concrete slab soffit area), produce less noise, dust and construction waste, and eliminate need of replacement rebars for specified corrosion range and rebar size. R²M² is the result of a collaborative research project, supported by the Innovation & Technology Fund (ITF), where Chun Wo has partnered with the Hong Kong University of Science & Technology and the Nano & Advanced Materials Institute (NAMI).

Now, R²M², having secured the support from the Buildings Department and Housing Department in research phase of the project, is entering the Public Sector Trial Scheme (PSTS) with the support from the Architectural Services Department. In the PSTS, R²M² will be applied in an actual environment, ensuring that the repair processes done previously in the laboratory can be repeated, achieving the target consistency in workmanship, quality, and performance.


A comparison between R²M² and conventional repair technology | A mock-up demonstration of corroded rebar and repairing method