Andrea Del Grosso

A long-term static monitoring experiment on R.C. beams: damage identification under environmental effect

The authors have been conducting a static continuous monitoring experiment to assess the validity of some damage detection algorithms, consisting in non-model-based statistical data processing, previously validated, even for small levels of damage, on numerically simulated 2D finite element models of simply supported and continuous beams. Tests have been conducted in Italy on two specimens of pre-stressed R.C. beams equipped with fibre optic strain sensors and temperature sensors and placed outdoor. During the tests, several events have been artificially produced: a ballast load has been positioned on the beams and various known levels of damage have been introduced. One of the two beams was kept intact for reference. Preliminary data processing has disclosed substantial differences between the numerical simulations and the measurements obtained on the field for the case of simply supported beams. This paper shows that environmental variations have a great effect on measurements and should be correctly removed from the strain time histories before a reliable damage detection procedure can be successfully applied.

Monitoring of harbor piers with fiber optic displacement sensors

SOFO ius a structural monitoring system using fiber optic deformation sensors. It is able to measure deformations between two points in a structure, which can be from 20 cm up to 10 meters (or more) apart with a resolution of two microns (2/1000 mm) even over years of measurements. The system is composed of optical deformation sensors adapted to direct concrete embedding or surface mounting, the cable network, the reading unit and the data acquisition and analysis software. The system is particularly adapted to precise short and long- term deformation monitoring of large structures. An array of more than 60 sensors have been installed on the pier of San Giorgio Levante in the Genoa harbor. These sensors allow the measurement of the pier displacements during the dredging works, ship docking and in the long term. The sensors measure the curvature changes in the horizontal and vertical planes and allow a localization of settlements with a spatial resolution of 10 m over a total length of 400 m. The sensors can be measured automatically and remotely. This paper presents the sensor installation and the results from the first monitoring period.

Smart Structures with Fibre‐Optic Technologies

A number of smart structures have been proposed, and some of them realized, to reduce the effect that seismic motions induce on the structure themselves. In particular, active and semi‐active control devices have been studied for being applied to buildings and bridges in seismic prone regions. The heart of the application for these devices consists of a network of sensors and computational nodes that produces the input to the actuating mechanisms. Despite the initial enthusiasm for these developments, only a few practical applications involving active devices have been implemented to‐date, the main reason residing in questions concerning the reliability of active systems over time. Nevertheless, the allocation of sensory systems and computational intelligence in structures subjected to earthquakes can provide very important information on the real structural behavior, provide self‐diagnosis functions after events, and allow for reliability estimates of critical components. The paper reviews several recent...

Analysis of long-term deformation data from the San Giorgio harbor pier in Genoa

In the framework of a large-scale monitoring program conducted by the Port Authority of Genoa, the east quay wall of the San Giorgio pier has been equipped with an array of more than 60 SOFO fiber optic sensors for continuous monitoring. These sensors allow the measurement of the pier displacements during the dredging works, ship docking and in the long term. The sensors measure the curvature changes in the horizontal and vertical planes and allow a localization of settlements with a spatial resolution of 10 m over a total length of 400 m. The system is in operation since fall 1999, and data has been collected automatically and continuously since then. This paper is intended to present the first analyses and interpretations performed on the monitoring data. Correlation of raw data and curvature analysis to environmental conditions is also presented.

Directions for the design of energy efficient kinematics in adaptive solar building envelopes

The development of adaptive building envelopes is receiving increasing interest in contemporary architecture, as it strives to cope with several requirements such as energy saving and harvesting (or mitigating environmental actions), improving performance and, finally, aesthetics. Actual implementation fundamentally concerns external “skins” (i.e. adaptive facades), but internal “skins” (e.g. adaptive ceilings) may also be developed. The engineering aspects related to the above developments are quite complex and involve different behavioral models to be merged within the adaptive strategy. In the present paper, a study is presented that concerns the conception of an adaptive origami-like solar skin. The main design issues in managing the kinematics of the envelope are then identified and the envisaged solutions, to be developed in the next stage of the research, are discussed.

Unconventional Structural Forms in Pedestrian Bridge Design

Andrea E. Del Grosso, born 1945, graduated in civil engineering at the University of Genoa, Italy, in 1968. He is currently fullprofessor of structural eng. at the Dep. of Civil Env. and Arch. Eng. of the same University. xxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxx x Paolo BASSO PhD student University of Pavia Pavia, ITALY paolo.basso@unipv.it

Automatic and remote deformation monitoring of the genoa san giorgio pier using SOFO sensors

SOFO is a structural monitoring system using fiber optic deformation sensors. It is able to measure deformations between two points in a structure, which can be from 20 cm up to 10 meters (or more) apart with a resolution of two microns (2/1000 mm) even over years of measurements. The system is composed of optical deformation sensors adapted to direct concrete embedding or surface mounting, the cable network, the reading unit and the data acquisition and analysis software. The system is particularly adapted to precise short and long-term deformation monitoring of large structures. An array of more than 60 sensors has been installed on the pier of San Giorgio Levante in the Genoa harbor. These sensors allow the measurement of the pier displacements during the dredging works, ship docking and in the long term. The sensors measure the curvature changes in the horizontal and vertical planes and allow a localization of settlements with a spatial resolution of 10 m over a total length of 400 m. The sensors can be measured automatically and remotely. This paper presents the sensor installation and the results from the first monitoring period..