Crack Estimation of Beam Under the Moving Mass Using the Dynamic Characteristics Based on Two Contact Point Theory

摘要

It is important to identify the presence of damage present in the structures like bridge which undergoes the excitation due to moving vehicles. In such type of problems, modal analysis and dynamic displacement response analysis are not sufficient to portray the crack presence. The presented work emphases on the analysis of acceleration response to investigate the crack presence. A mathematical model is developed by considering the two masses with fixed distance between them traversing on the Euler-Bernoulli beam having a crack. The acceleration response analysis can be effective to present the qualitative explanation of the fault present in the beam. A key features of the acceleration response of beam having a crack includes discontinuity at the crack location which vary with change in distance between the front and rear wheel and a greater response value compare to that for healthy in the last phase of travel from the time front wheel exits the beam. However, the effectiveness of the presentation of the crack through acceleration response depends upon the fixed distance between the front and rear wheel and the bridge length. The discontinuity will be higher for the higher ratio of distance between the front and rear wheel to the bridge length.