Combined NDT techniques in civil engineering applications: Laboratory and real test

Abstract

The damage of concrete structures calls for effective methods for condition evaluation and maintenance. The usual destructive testing has many disadvantages in Civil Engineering because involves the physical destruction of specimens to evaluate mechanical and structural characteristics. On the contrary, Non-Destructive Tests (NDT) are able to investigate different structures with high resolution, low time consuming and relative few costs. This resulted in development of several NDTs techniques for monitoring civil infrastructures. Accurate analysis of the physical parameters that characterize the structures is made possible by the spread of instruments that are actually more precise and economical. However, failure to use non-destructive tests effectively can be disastrous in operation of structures restoration or buildings rehabilitation. Applied geophysics is able to provide many information on the state of preservation and quality of engineering work. This work has investigated the skill of Ground Penetrating Radar (GPR) also applied in tandem with Infrared Thermography (IR) and Electrical Resistivity Tomographies (ERT) for the characterization and monitoring of building structures in laboratory and in-situ conditions. Two experimental cases are realized: in the first one GPR and ERT were performed in full scale laboratory conditions where a road segment was investigated in different conditions; in the second test, a radiant floor was investigated with comparison of results obtained with GPR and IR. The study demonstrates the feasibility of integrating the collected data obtained with non-destructive testing to enhance knowledge of engineering issues.