ABSTRACT
New technologies are permanently under development in the Civil Engineering world to push forward the limits of construction. Several decades before, the construction of a bridge like RionAntirion was only a dream due to the high environmental difficulties to build a bridge at this location over a fault. Nobody would have thought being able to build a 3.3 km span suspension bridge like the Messina Straight Bridge. The progress of the science allows every day to understand better the behaviour of the elements thanks to numeric simulation and calculation tools that are made available through the increase of the power of the computers. Very efficient calculation tools are available to any designer that has the right skills/experience to perform the work. Pushing forward the limits means to come closer and closer to the origin of the limits (earthquake consequences simulations, wind behaviour simulations, …) and for this goal the laboratory tests are very valuable. The counterpart of it is that the designs are very specialised and focussed on specific managements of risks, and this has to be done based on specific hypothesis. If one of these hypothesis appear to be wrong after having built the structure, or should any important characteristic change through the lifespan of the structure, then the behaviour of the structure will not be according to what has been expected, and therefore the life of the structure might be reduced, with high evident financial consequences due to the increased maintenance costs, or earlier renewal of the facility. Building a structure like Messina Bridge has its own intrinsic risks, like for example flutter. Although these aspect are well understood, and designers perform all the state of the art calculations to prevent it, it remains that the bridge has to behave like it has been designed for during strong winds, and that a careful follow up of the essential elements that are necessary for the correct behaviour of the bridge is a critical issue to manage the flutter risk.
