Assessment of flood and wind driven rain impact on mechanical properties of historic brick masonry

As a result of increased rainfall and flooding the building fabric of historic structures in exposed areas are likely to be subject to higher and more sustained moisture content levels, along with experiencing an increased frequency and severity of wetting and drying cycles. This study aims to evaluate the impact of such cyclic wetting and drying on the mechanical behaviour of historic brick masonry. The reported results are obtained from a series of weathering and mechanical tests carried out on clay bricks and masonry specimens. The weathering test regime derives from analysis of observed weather data, combined with review of similar existing test protocols. Similarly, a modified mechanical test procedure is applied to simulate fatigue observed in the field. The results indicate that exposure to the weathering tests results in a reduction of masonry shear strength. This is discussed within the context of wider work carried out at a case study location, and highlights the value of designing a weathering regime that can more closely replicate the in-situ weathering processes. In this way the data collected in this experimental programme is shown to be suitable for use in contextual analysis of individual historic masonry case studies, with respect to climate change and the associated alteration of wetting regimes