According to the fuzzy probability theory in fuzzy mathematics

a comprehensive fuzzy probability evaluation model of sand soil liquefaction is presented. In order to consider the fuzziness of weight factor

the fuzzy weighted value is suggested to avoid the uncertainties while determining the weight factor. The following factors such as earthquake intensity

standard penetration number

mean diameter and effective over burden pressure are selected as the evaluating indices; and liquefaction grades are classified as the non-liquefaction

slight liquefaction

medium liquefaction and serious liquefaction in the evaluating model; so the evaluation results can be more precise. The theoretical model is successful applied to evaluating liquefaction of sand soils in practical engineering; and the rationality and effectiveness of the method proposed is demonstrated through 22 examples.