This thesis presents a comprehensive modal analysis on an asphalt roller, focusing on optimizing excitation and measurement point selection for accurate characterization of the structure’s dynamic behavior. The thesis aims to find out how to select excitation points that ex-cite all mode shapes within a specific frequency range and to find out how to select measurement points that capture the dynamic behavior and mode shapes of the structure within the same frequency range. The method used is an action research method that includes four phases: planning, action, observation, and reflection. The planning phase involves numerical modal analysis, simulations, and selection of excitation and measurement points. The action phase includes experimental measurements preliminary tests, and the actual testing of the structure. The observation covers extracting modal parameters from measurement data and comparing results with simulation predictions. Reflection focuses on evaluating results and adapting the decision-making accordingly. The EODP method provides practical excitation points that successfully active modes consistent with the simulations. The minMAC GA approach identifies measurement points that capture the asphalt roller’s essential dynamic behavior, despite challenges with modal parameter extraction. Even though the mode shapes are not well separated due to the complexity of the structure, high-quality identification of mode shapes was achieved considering impact excitation which gives great insight into the asphalt roller’s dynamic properties. Overall, this research contributes to the understanding of modal analysis on complex mechanical structures, providing effective methods for excitation and measurement point selection. The findings in the study can inform the design and maintenance of similar structures in various engineering applications.

Free body diagrams of an Asphalt Roller were designed for several load cases and used for an optimisation study. Assumptions for the load calculations for each load case were carried out in MATLAB®. The Roller was built in I-DEAS® and the results were compared with the theoretical results / F.B.D av en Asfalt Vältar designerades för olika last fall och användas för en optimisation studier. Antagandena för de olika last beräkningarna utfördas i MATLAB. Vältar byggdes i I-DEAS och resultaten jämfördes med de teoretiska. / Kungsmarks vägen 97 37144 Karlskrona - Sweden Telefon 045510316