Load tests are among those thought for structures whose actual resistance characteristics are requested for various reasons.
They aim at checking the correspondence between the theoretical and the real behaviour of structures. They are carried out on new buildings or rather on structures whose constituent elements (e.g. type of floors, beam dimension, etc.) and the shape characteristic parameters (moment of inertia) and of the material (modulus of elasticity) are known and reliable. Moreover, the constraint conditions can be deducted with a good approximation.
We often deal with structures whose actual resistance characteristics are requested for various reasons. Common cases include damaged or obsolete structures (fires, explosions, unknown anomalies, etc.) or those with lower characteristics than those foreseen in the planning.
In all these cases the preventive intervention must consist in measuring the resistance conditions so that the best decisions can be taken considering objective data rather than simple hypothesis.
Methods to detect deformation
These tests allow to identify the saggings of the most relevant sections (at half, at the external bearing and at ¼ and ¾ of the span) under the action of the applied loads. To detect the deformation some electronic sensors (inductive transducers), linked to an electronic unit, recording the saggings at the various points, will be used.