Reviving the built environment
It is well-recognized that BBR technology promotes leaner new construction, but what about maintenance, retrofit and restoration or renovation (MRR) projects? With the three ‘Rs’ – Reduce, Reuse, Recycle – playing an ever greater role in a cost-conscious and environmentally aware world, specialist techniques and technology used by BBR Network Members are also delivering leading edge green and economic solutions.
The need for the BBR Network’s range of MRR techniques arises from a number of factors. Often, it is a case of repairing damage whether through prolonged or heavier-than-planned usage or insufficiencies in the original design of a building – although constructed to the highest standards of the day, several decades ago. However, sometimes such techniques are used to assist the repurposing of a building or structure or to ensure its continued life through a change in environmental conditions.
Four key techniques feature again-and-again in our project portfolio:
- Fiber reinforced polymer (FRP) application
- Bearing replacement
- External post-tensioning
- Impressed current cathodic protection (ICCP)
These are sometimes used together and sometimes with other specialist procedures, such as heavy lifting.
FRP laminates and sheets are used as bonded reinforcement for the strengthening of structural elements of concrete, masonry, stonework and timer. Such applications arise due to enhancement of load carrying capacity due to changed usage, upgrading to satisfy current building codes, seismic strengthening (increased load and ductility), alteration to intended structural form, rectification of design or construction mistakes, and enhanced durability.
Typical applications include:
- Columns – axial load enhancement
- Beams – flexural and shear enhancement as well as seismic strengthening
- Walls – provision of shear strength to concrete, masonry walls, webs in box girders, abutments and shear walls
- Slabs – flexural enhancement and deflection control
- Durability – protection against further degradation and providing additional structural capacity of any structural elements