Risk analysis on swell–shrink capacity of expansive soils with efficacy coefficient method and entropy coefficient method

• A novel analysis model was established for the classification of expansive soils.
• The efficacy coefficient method was newly applied for the classification.
• Entropy (information theory) was applied to determine the weight coefficient.
• Reasonable agreements could be obtained and would provide consults for further study.

Expansive soils can cause enormous damage to buildings and structures, and have been accepted as a risk source for the population. Risk analysis on swell–shrink capacity is essential for evaluating the stability and safety of expansive soils. A novel analysis model was put forward with efficacy coefficient method and entropy coefficient method for the risk analysis. The efficacy coefficient method was adopted in dimensionless treatment based on the theory of multi-objective programming, which was newly adopted for single efficacy coefficient to describe the influence of the considered evaluation index. Meanwhile, the entropy coefficient method was applied to determine the weight coefficient for each index. Then the single efficacy coefficient and the weight coefficient were used for calculating the total efficacy coefficient, which was presented to specify the grade of swell–shrink capacity for the evaluation samples of expansive soils. Furthermore, the classification results of the proposed method were compared with gainable results, and qualitative consistencies could be gained as expected. Therefore, the established model based on the efficacy coefficient method and entropy coefficient method is valid to predict risk analysis on swell–shrink capacity of expansive soils. Moreover, the presented model is more feasible and effective, which could provide useful ways for classification, risk management and design of projects on expansive soils as well as other engineering applications.