Distributed sensor network for structural characterization of buildings aggregates: discussion about aspects affecting measurement uncertainty

In order to set integrated procedures involving geotechnical and structural aspects finalized to buildings diagnostics, uncertainty aspects are discussed concerning three-axis accelerometers and inclinometers for a distributed sensor network, allowing us to operate in a selective manner and preferring the most critical situations. Main topics to be considered for the uncertainty evaluation of measurements and of information to be used for building diagnostics are discussed. As a first step of the whole procedure of uncertainty evaluation, particular attention is dedicated to the calibration of sensors to be used, taking into account the requirement of simple and inexpensive solutions for both sensors and test benches. Experimental results show that satisfactory calibration accuracy could be achieved, also for the low frequency range, 0 to 10 Hz, but it strongly depends on the motion positioning with respect to the vertical axis, on the imposed motion law and, finally, on the parameter used as the reference. Requirements to be satisfied by the sensor are also analysed.