Modal Analysis of Multi-Panelled Concrete Pavement Airport Runway Using Finite Element Technique

PurposeThe modal analysis identifies a structure's inherent dynamic characteristics, such as eigenfrequency and vibrational mode shapes. It has been widely used for many different purposes during the last few decades. Still, more consideration must be given to investigating the modal characteristics of the multi-paneled concrete pavement airport runways.MethodsThis study offers a finite element (FE) based modeling approach for the modal analysis of a concrete pavement airport runway, specifically focusing on a jointed plain concrete pavement (JPCP) system, which will aid in improving runway pavement design, precisely adjusting the eigenfrequencies by distributing mass and stiffness of the structure to avoid resonance and ensure structural integrity. A FE model in three dimensions of a concrete pavement runway was developed and evaluated using the ANSYS software through the FE-based approach rather than closed-form solutions. A mesh convergence assessment confirmed the precise simulation of the proposed airport runway FE model with the least element count and exact results.ResultsThe proposed FE model's resultant eigenfrequencies and mode shapes have been evaluated while taking into consideration fifteen distinct vibrational modes, which confirms the accomplishment of the requirement of at least 90% effective mass of the structure's involvement. It was noticed that the eigenfrequency value raised with higher modes that showed complex deformation patterns such as a combination of flexure, translation, shear, and torsion. In addition, a case study was performed to categorize critical factors that affect the vibrational response of concrete pavement runways, which are the major findings of the present study. The present computational methodology was validated using a non-closed form numerical problem from the earlier study, and a good correlation between the present modeling approach and previous numerical and analytical results was found, which affirms the reliability of FE modeling in simulating complex structural behaviors, aiding in designing safer and more efficient runways.ConclusionThis study will also provide the base for further assessing the concrete pavement runway dynamic-transient response by incorporating the moving aircraft load.