Thermography (IR) allows global visualization of temperature distribution on surfaces with high accuracy. This potential
can be used for visualization of fluid mechanics effects at the intersection of laminar and turbulent flows, where
temperature jumps appear due to convection and friction i.e. for the optimization in the design of airplane geometries. In
civil engineering too it is the aspiration of the modern engineer of light weight structures to meet singular loads like wind
peaks rather by intelligent structures and materials than by massive structures. Therefore the "Institute of Conceptual and
Structural Design" of the Technical University of Berlin (TUB) is working on the development of adaptive structures,
optimized geometry and intelligent microstructures on surfaces of structural elements. The paper shows the potential of modern computational fluid dynamics (CFD) in combination with thermography (IR) to optimize structures by visualization of laminar-tumultuous border layer currents. Therefore CFD simulations and IR
wind tunnel experiments will be presented and discussed. For simulations and experiments - artificial and structural
elements of the cable-stayed Strelasund Bridge, Germany, are used.
In this paper a new approach for quantitative non-destructive testing (NDT) of near-surface structures in civil engineering (CE) with active thermography is presented. It adopts the method known as pulsed phase thermography (PPT) for the special requirements of NDT-CE and was developed in a German research project of the Federal Institute for Materials Research and Testing (BAM) in cooperation with the Technical University of Berlin. The new quantitative concept that might be understood as a square pulse thermography in frequency domain or an amplitude-expanded PPT with square pulse heating is based on the thermal diffusivity of the material and the characteristic frequency of the negative maximum phase and amplitude contrast. It aims at complementing the established approaches for defects depth calculation for measurements with long heating and observation times quite usual at active thermography in CE but is easily extendable to other fields of application.
After an introduction to the basics of active thermography in CE and the thermography concept of BAM, qualitative results of several case studies will be presented. The main focus of the last section of this contribution is on applications of the new quantitative approach at test specimens of BAM to determine the concrete cover of artificially manufactured defects.
New fiber-optic applications have been demonstrated within the last years, mainly due to the unexpected progress in manufacturing of solarization-reduced fibers. In meantime, analytical systems including UV-fibers and spectrometers are in operation including the wavelength region from 200 to 250 nm.