Interpretive Structural Modeling (ISM) of Bolted Joint Subjected to Dynamic Loosening under Soft Foot Condition

Abstract

— In this paper thirty nine factors responsible for the dynamic loosening, under soft foot condition, of a bolted joint have been enumerated and its Interpretive Structural Modeling (ISM) has been developed. In this systematic approach of ISM, first of all a concept model of the problem has been formulated, followed by the formulations of Structural Self-Interaction Matrix (SSIM) and Reachability Matrix. The level of significance of each factor has been derived by level partitioning. The initial digraph is prepared on the basis of the canonical matrix. ISM based model is finalized after checking for conceptual inconsistency and necessary modifications. The MICMAC analysis is also conducted with the help of driving and dependence diagram, which states that factor 31 (vibration loosening) and 36 (additional stresses in the bolt) are the major threat for joint integrity and needs more attention.