Introduction

The distributed strain transducer made of composite material (New Smart distributed Transducer made of Hybrid glass and carbon fibers, NSHT), can be used in various fields (from monitoring landslides, bridges, viaducts and other infrastructural works to structural elements of buildings under observation). The proposed transducer integrated in monitor systems, removes many implicit limitations of the conventional monitoring systems. The main limitations of existing technologies concern: degradation over time; monitoring in places or infrastructures that present difficulties of access, as well as the extent of action; multiple use for monitoring. The present invention overcomes these limitations because: the optical fiber is protected by a coating made of a very strong composite material which allows to avoid mechanical or chemical degradation over time; it is of the distributed type and allows to reconstruct (with high spatial resolution) the thermal and / or deformation profile of a particularly large portion of an engineering work and / or of a terrestrial area (even reaching lengths of hundreds of meters); it can be used both for the monitoring of landslides and for the monitoring and structural reinforcement, in particular, it allows to recognize in a time compatible with the definition of an “Early Warning” system the reactivation along the vertical of pre-existing sliding surfaces and the position of newly formed sliding surfaces.

Technical features

The transducer is developed with a distributed fiber optic sensor. A cheap optical fiber for telecommunication will be inserted between two layers of composite material whose thickness is linked to the weight (g/mq) of the fiber to be used. Different types of resin (polyester, vinylester, epoxy) will be considered in the project. Deformation distributed transducers will be realized considering three different types: 1) Optical fiber between two layers of glass fiber with polyester resin;  2) Optical fiber between two layers of carbon fiber; 3) Optical fiber between a layer of glass fiber and one of carbon (Hybrid). The New Smart distributed Transducer become essential to develop innovative Early Warning Systems (EWS) for geotechnical application and “Structural Health Monitoring and Restoration” (SHMR) which is an effective enhancement of simple “Structural Health Monitoring” (SHM) as it is intended till now.

Possible Applications

• Distributed fiber optic sensor;
• Geotechnical and structural monitoring;
• Low enthalpy geothermal energy resources;
• Long-term diagnostics of infrastructures;
• Early Warning System;
• Structural Health monitoring.

Advantages

• Resolution of contact problems by using compatible materials;
• Protection function for the transducer;
• Transmission of stresses to prevent the breaking of the transducer.