Cantilevered Balconies
THE SITUATION
Following the collapse of gallery slabs in Leeuwarden in 2011, inspections were carried out throughout the Netherlands on cantilevered concrete gallery and balcony slabs. Due to corrosion of the reinforcement, reduced load-bearing capacity was observed in many cases.
A reinforcement method was developed by B+BTec, Vogel B.V. and ABT that offers a solution in these situations.
THE PROJECT
The solution was found in drilling holes in the end of the cantilever into the underlying edge beam or floor. The finish can be left intact in this process. In these holes carbon reinforcement bars (CFRP bars or Carbon Fiber-Reinforced Polymer) are installed with an Epoxy mortar. For detailed information on the repair of cantilevered gallery floors, please visit the website of Vogel B.V.
Extremely precise drilling is essential for the chosen solution. For this purpose, B+BTec designed a special drilling system with core bit guide that can drill the small diameter (Ø20/28 mm) over a long distance (4.5 m) through the relatively thin concrete floor.
The special clamping system allows the machine to be reppositioned quickly and the fold-away slide makes changing the diamond drill bits very easy.
Because diamond drilling is used, there is hardly any inconvenience. Diamond drilling is dust- and vibration-free and also produces relatively little noise.
The drilling is done from the outside so that the galleries remain accessible during the repair.
RELATED
ADVANTAGES
- Complete restoration of structural safety
- Minimal inconvenience to residents during execution
- Invisible repair method
- No damage to cover floor or coating
- Resistant to chloride attack
PROJECT PARTNERS
