Modeling and experimentation of vibration transmission through an angled joint

Analysis of vibration transmission and reflection in beam-like engineering structures requires better predictive models in order to further optimize structural behavior. Various studies have used flexural and longitudinal structural wave motion to model the vibrational response of angled junctions in beam-like structures, in order to better understand the transmission and reflection properties. This study considers a model of variable angle joint which joins two semi-infinite rectangular cross-section beams. In a novel approach, the model allows for the joint to expand in size as the angle between the two beams is increased. Thus, making the model a good representative in wide range of angles. Predicted results are compared to an existing model of a joint between two semi-infinite beams where the joint was modeled as a fixed inertia regardless of the angle between the beams, thus limiting its physical representation, especially at the extremes of angle. Results from experimentation were also compared to the modeling, which is in good agreement for the range of angles investigated. Optimum angles for minimum vibrational power transmission are identified in terms of the frequency of the incoming flexural or longitudinal wave. Analysis of the effect of changing the joint material properties is also reported.