An experimental approach for developing a building damage matrix for the flood-affected vernacular housing typology

The study aims to investigate flood-related damage on earthen buildings using an experimental analysis. Wattle and daub method is the main construction technique used in the coastal part of West Bengal, India. Housing damage caused due to floods is often poorly compensated due to the absence of an established loss-assessment scale for vernacular housing typologies a predominant construction practice in the study region. Earthen buildings developed using various techniques have proven functional, while offering multiple benefits such as cost and energy efficiency along with thermal comfort. Despite the benefits, the functionality gets significantly reduced due to their susceptibility to flooding instances that are likely to increase with aggravating extremes as a result of changing climate. The contribution of vernacular or traditional construction techniques if integrated with disaster resilience techniques shall prove indispensable in reducing the shortage of 29.6 million dwelling units for the low-income rural households by the year 2022 in the study region.

The qualitative assessment of the damage process involves visual inspection of the sealed model of the building component behaviour and a non-destructive test. Under the qualitative process, the sample is tested under Universal Testing Machine (UTM) machine to understand the loss of compressive strength at each stage of flooding. The process will result in a damaged matrix which is an array of loss percent for various depth–duration combinations. The matrix will help in identifying corresponding flood losses and deciding repair costs for varying flood intensity. In addition to this, the process can be identified as an imperative step while suggesting an alternate construction technique in such a flood-affected region.

Keywords: Flood damage,Vernacular housing, Damage matrix, Non-destructive tests, Destructive tests