Experimental investigation of a small-scale bridge model under a moving mass

The dynamic response of a small-scale bridge model under a moving mass is investigated. The analysis is based on the continuous Euler-Bernoulli beam theory. By expanding the unknown structural response in a series of the beam eigenfunctions, the given problem is reduced to the solution of a set of second order linear differential equations with time varying coefficients. The analytical solution is validated through a series of experiments. A small-scale model is designed to satisfy both static and dynamic similitude with a selected prototype bridge structure, and a set of necessary similitude conditions for the given problem is provided. Attention is paid, in particular, to satisfaction of the mass similitude requirement, often constituting one of the main difficulties in the design of small-scale dynamic models. It is shown that experimental results are in good agreement with theoretical predictions, thus validating the analytical procedure.