Vittoria bridge in Bassano del Grappa (VI)

Reinforced concrete condition was verified through access and positioning system by ropes.

Structural analysis was carried out through sufficient sampling of materials to create a statistical database. Tests focused on the right side bridge arches, being at the greatest risk of degradation due to water infiltration.

Visual analysis allowed for reinforced concrete degradation verification, separating clearly damaged areas from those beginning to suffer damage requiring further diagnosis. Magnetometric testing (BS 1881-204:1988) analysed the metal bar strength of reinforced concrete as well as measuring the thickness of concrete covering and the size of bars used.

Drilling dust sampling allowed determining the depth of concrete carbonatation (UNI 9944:1992). Rebound concrete testing was carried out with a Schmidt hammer (UNI EN 12504-2:200). The high level of structural carbonatation makes results of these tests unreliable and therefore, cannot be extended to all the structures.

Ultra-sound velocity measurements were carried out using an impulse generator, a couple of transducers, an amplifier and an electronic time measurement system (standard UNI EN 12504-4:2005). Measurements were taken directly (transparently), transmitter positioning (T) one side ultrasound with receiver (R) opposite the concrete structure under analysis. Ultra-sound measures were also taken with the transducers, positioned according to a previously set up grid, and then analysed using tomographic methods for the analysis of velocity distribution and propagation of longitudinal waves across plane sections.

According to modality of data acquisition, it was possible to lay down a statistical analysis of the data logged.