Safety assessment of existing subgrade retaining wall based on a combined Weighting-TOPSIS evaluation method

The safety assessment of existing retaining walls is currently a potential research direction in developing built environment. However, current assessment results are generally carried out by a single evaluation method with poor applicability and operability. Thus, this paper proposed a comprehensive safety assessment model for existing subgrade retaining walls. The qualitative and quantitative indexes were summarized systematically and then were weighted by the entropy weight method (EWM), interval analytic hierarchy process (IAHP), and improved radial movement optimization (IRMO) algorithm. With these indexes weighted, the safety situation can be assessed by the technique for order preference by similarity to an ideal solution (TOPSIS) method. The proposed method was applied to five cases. The results show that the method reduces the subjective arbitrariness in weighting calculation, making the evaluation more objective and reasonable. The model improves the accuracy and applicability of the safety assessment of existing retaining walls.