Coupling risk model of set pair analysis and stochastic simulation of triangular fuzzy numbers for the evaluation of shrink and expansion of the expansive soil

The risk evaluation of shrink and expansion of the expansive soil is essential to evaluate properly the engineering stability and safety. Herein a novel risk model for the analysis of the grade of shrink and expansion for the expansive soil was discussed by means of coupling set pair analysis with stochastic simulation of triangular fuzzy numbers. A concept of multi-element connection number of the set pair, which was consisted of evaluation index sets and classification standard sets of the grade of shrink and expansion, was described to express the hierarchy and fuzziness of membership between the evaluation sample and classification standard. Moreover, the triangular fuzzy number simulated by stochastic simulation method was presented to depict the changing process and fuzziness of component coefficients of discrepancy degree. Combined with the weight of evaluation index, the integrated connection number was calculated to specify the grade of the grade of shrink and expansion of the expansive soil of the sample. A confidence level of evaluation grade was also given corresponding to evaluation confidence interval. Finally, a practical example was used to confirm and to compare with the fuzzy mathematic method and extension method. The results show that the proposed method is more feasible and easy to operate, and the result is good. It can provide the reliability degree of evaluation result for risk design and risk management of projections on the expansive soils.