Estimation of Joint Rotation Constant for Bolted Joints with Pre-torque and Effect of JRC on Natural Frequency

The design and analysis of launch vehicles heavily rely on a parameter known as joint rotational compliance (JRC), particularly at flight intersection joints (FIJs). Given the absence of reliable theoretical or numerical models, we have outlined a methodology for evaluating JRC using finite element analysis (FEA). The primary objective of this chapter is to develop a computational model that can simulate and analyze the variation in the values of joint rotational compliance (JRC) for bolted joints embedded within shells subjected to loading conditions involving constant bending moments. These loading conditions can be applied with different orientations and moment values. Finite element analysis (FEA) is employed to generate various configurations, enabling the calculation of deflections and the subsequent determination of JRC values for each loading scenario. The impact of JRC on natural frequency and mode shape has been investigated, and a novel approach to predict JRC has been proposed to align with previous experimental research findings.