Loess collapse is a type of collapse characterized by frequent occurrence and widely distribution in Yan′an region.The loess collapse type in Yan′an region includes water wetting

salt erosion

engineering excavation and loess cave dwelling based on geological environmental conditions and human engineering activities.Materials of 356 loess collapses were summarized by means of geology survey.Then the correlations between loess collapse types and loess collapse were studied by using of contribution rate method.The results show excavation engineering and loess cave dwelling have maximum contribution rate

salt erosion has moderate contribution rate and water wetting has minimal contribution rate.The conclusions verified the practical situation of loess collapse development in Yan′an region.It throws light on disaster prevention and mitigation in other regions.