We analyse the performance of solidly mounted bulk acoustic wave resonators under induced mechanical stress to explore their viability as strain sensors. The resonators are made of polycrystalline AIN piezoelectric thin films containing uniformly tilted microcrystals to excite both longitudinal and shear modes. The resonators are grown on top of silicon bars that are fixed at one or two edges using two home-made apparatus specifically designed to induce deformations of several hundreds of microstrains. The induced strain causes frequency shifts of tenths of MHz, yielding strain coefficients of the resonant frequency (SCF) up to-71% per unit strain (-0.71 ppm/fie). The influence of the nature of the resonant mode (shear of longitudinal), the electromechanical coupling factor and the operation frequency on the SCF is analysed.

The new viaduct over the Cadiz Bay includes a removable deck to allow the navigation of large floating structures, higher than the 69 m clearance of the main cable-stayed span of the bridge. For this purpose, a 150 m long simply supported span was designed, which can be assembled and disassembled. The steel deck, weighing 4,000 metric tons, was completely manufactured onshore, the challenge being to move such a massive structure to its final position above the piers. It required for several heavylifting maneuvers, such as land transportation and load-out with two 6 x 28 axle lines of self-propelled modular transporters (SPMTs), sailing with a 100 m long barge and positioning the deck in-between the piers with a tight gap, a lifting with eight strand jacks 850 T capacity each and a final transversal shifting. The aim of this paper being to describe all the activities and the heavylifting equipment employed for the assembly of such a massive deck.

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