Structural Enhancement Using Resin Bonded Plate and Fabric

Plate bonding is a well established concept whereby steel plates are applied to plane concrete surfaces using epoxy resin adhesive and bolted fixings. The technique is used to provide additional resistance to bending, improve load capacity or reduce deflections, and is particularly useful as a retrospective method when changes in use in a building, or perhaps increased vehicle loadings on a bridge structure need to be addressed.

Ram Services Limited were one of the earliest exponents of steel plate bonding in the UK, and pioneered a technique where plates are applied to a structure “dry”, and the resin adhesive then introduced by injection methods. Such a procedure is particularly useful where substrates are uneven, and has been used successfully to bond steel plates to riveted steel plate girders.

Carbon fibre based fabric is now also used to strengthen columns and beams using a wrapping technique. 

Single or multiple layers of uni or bi-directional fabric are impregnated with resin adhesive and applied to sections such as beams and columns to improve strength.

 The technique is used particularly to improve bursting or impact resistance for columns on high way bridge structures.

Above - carbon fibre plates bonded to soffit of minor bridge in Cumbria (left) and M60/A34 motorway bridge (right)

Schemes undertaken by Ram Services include some of the well documented early uses of plate bonding such as the M1 Brinsworth Bridge at Sheffield (for South Yorkshire County Council), and more recently the first and most extensive use of carbon fibre plates for the UK Highways Agency on the A34 Barnes Bridge over the M60 south of Manchester.

Right - carbon fibre plates strengthening vertical walls of underground pump chamber