Sep 2 2009
CERAM, a global expert in materials testing, analysis and consultancy, has published a Design Guide for Masonry Reinforced by Bond Beams to Resist Lateral Load (www.ceram.com/structures). The Guide outlines the use of a bond beam system commercially known as the WI Beam System to replace wind posts as the means of subdividing large walls and strengthening them against lateral loading. The report is the result of a three year study to assess lateral load resistance of walls built using this system.
The study on which the design guide is based involved the testing of four walls, each 8m long and 5m high, under lateral load. "Instead of subdividing the walls using wind posts, we used bond beams placed at approximately one third and two thirds of the height," explains Dr Geoff Edgell, Head of Building Technology at CERAM.
"The bond beam in itself is not a new idea; it is essentially a series of trough shaped units where the void is reinforced with steel and concreted. However, the system we used in this study introduces shear transfer rods - an innovative method of providing additional support for large walls." Shear transfer rods connect the bond beam with the blockwork courses above and below it. In this way the three courses act compositely to provide a stiff reinforcing layer.
The study has demonstrated that such walls can resist significant wind loads, in excess of 6kN/m2 before failure, and the Design Guide lays out general recommendations as to the design of concrete blockwork walls using the WI Beam System. The Guide has been co-authored by Neil Tutt (Jenkins and Potter), Andrew Best (Buro Happold), Geoff Edgell (CERAM) and Hamish Corbett (Wembley Innovation).
As one of the leading testing facilities in the UK, CERAM provides testing of raw materials, finished products and full scale structures both in the laboratory and on-site. CERAM's experts have developed new and bespoke testing solutions for the most intractable construction and materials problems.