A method to quantify the safety appraisal rating of masonry structures

A comprehensive method for quantitatively appraising the safety rating of masonry structures is proposed which is able to reflect the difference in the safety level and is easy to be applied in practical engineering, contrary to most presently available qualitative and quantitative methods. Analytic hierarchy process (AHP) and fuzzy theory were introduced to establish a hierarchical evaluation model which divides the factors influencing the masonry structure safety into three levels: sub-units, sub-items and check-items. The weight vector of each level was calculated by determining the judgement matrix while the assessment matrix was determined using grey clustering method based on the field data. Finally, the comprehensive assessment vector of the masonry structure was calculated by fuzzy linear transformation from the lower layer to the upper level. We applied this method to a practical masonry structure. The result was not only in agreement with the appraisal result according to Chinese Standard but also gave more quantitative information about each of the affecting factors. As shown by the practical case, the newly developed method is feasible and applicable in practice