Can acceleration-only measurement tell the health of a bridge?

This article claims that the structural health of a bridge can be evaluated based only on acceleration (vibration) measurement. 

“Can bridge collapses be prevented by continuous structural monitoring?” https://link.medium.com/PzpB0IlopS

This would definitely solve a lot of cost issues about monitoring a large number of existing ageing bridges. But the key question here is if it is actually possible to determine the health based solely on acceleration measurement. Sure, operational modal analysis can be done. Modal shapes obtained, natural frequency determined. Velocity and disolacement of oscillation  can be integrated and observes. But to get stiffness, you would have to know what is the actual load that gives you certain displacement and the load (excitation) is difficult to measure (varying traffic, wind etc.). 

I surely think it is good to gather the data, but can someone with more experience in the field elaborate on the feasibility of the idea? If we could get rid of strain gauges, fbgs etc, it would be a dream come true for structural monitoring engineers.