TY - GEN A1 - Weritz, Friederike A1 - Taffe, Alexander A1 - Schaurich, Dieter A1 - Wilsch, Gerd ED - Cruz, P. ED - Frangopol, D. T1 - Chloride determination for condition assessment and quality assurance by LIBS T2 - Bridge maintenance, safety, management, life-cycle performance and cost T2 - 3rd International Conference on Bridge Maintenance, Safety and Management - "Bridge Maintenance, Safety, Management, Life-Cycle Performance and Cost" CY - Porto, Portugal DA - 2006-07-16 KW - LIBS KW - Chloride KW - Concrete PY - 2006 SN - 0-415-40315-4 N1 - Serientitel: Balkema proceedings and monographs in engineering, water and earth sciences – Series title: Balkema proceedings and monographs in engineering, water and earth sciences SP - 333 EP - 334 PB - Taylor & Francis CY - London AN - OPUS4-13716 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weritz, Friederike A1 - Taffe, Alexander A1 - Schaurich, Dieter A1 - Wilsch, Gerd T1 - Detailed depth profiles of sulfate ingress into concrete measured with laser induced breakdown spectroscopy JF - Construction and building materials N2 - Sulfate attack constitutes a major risk of chemical aggression for concrete and other building materials. Mainly structures exposed to sewage waters and sulfate rich soils are affected. The measurement of sulfate ingress is important for damage assessment previous to repair works and for quality assurance of the effectiveness of protecting coatings or during concrete removal. Laser induced breakdown spectroscopy is introduced for the quantitative measurement of sulfur contents in building materials, providing detailed depth profiles and imaging element distributions with 1 mm spatial resolution. Detailed statistical evaluation is possible due to the spatial resolution and the fast measurement of the method. Practical applications of the method for damage assessment are demonstrated for three different sewage plants. KW - Laser induced breakdown spectroscopy KW - Sulfate attack KW - Sulfur content KW - Concrete KW - Sewage plant KW - Depth profiles KW - Element distribution PY - 2009 DO - https://doi.org/10.1016/j.conbuildmat.2007.12.016 SN - 0950-0618 VL - 23 IS - 1 SP - 275 EP - 283 PB - Elsevier Science CY - Amsterdam AN - OPUS4-18426 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weritz, Friederike A1 - Schaurich, Dieter A1 - Taffe, Alexander A1 - Wilsch, Gerd T1 - Effect of heterogeneity on the quantitative determination of trace elements in concrete JF - Analytical and bioanalytical chemistry N2 - Laser-induced breakdown spectroscopy has been used for quantitative measurement of trace elements, e.g. sulfur and chlorine, in concrete. Chloride and sulfate ions have a large effect on the durability of concrete structures, and quantitative measurement is important for condition assessment and quality assurance. Concrete is a highly heterogeneous material in composition and grain-size distribution, i.e. the spatial distribution of elements. Calibration plots were determined by use of laboratory-made reference samples consisting of pressings of cement powder, hydrated cement, cement mortar, and concrete, in which the heterogeneity of the material is increasing because of the aggregates. Coarse aggregate and cement paste are distinguishable by the intensity of the Ca spectral lines. More advanced evaluation is necessary to account for the effect of the fine aggregate. The three series of reference samples enable systematic study of the effects of heterogeneity on spectral intensity, signal fluctuation, uncertainty, and limits of detection. Spatially resolved measurements and many spectra enable statistical evaluation of the data. The heterogeneity has an effect on measurement of the sulfur and chlorine content, because both occur mainly in the cement matrix. Critical chloride concentrations are approximately 0.04% (m/m). The chlorine spectral line at 837.6 nm is evaluated. The natural sulfur content of concrete is approximately 0.1% (m/m). The spectral line at 921.3 nm is evaluated. One future application may be simultaneous determination of the amount of damaging trace elements and the cement content of the concrete. KW - LIBS KW - Heterogeneity KW - Concrete KW - Chlorine KW - Sulfur PY - 2006 DO - https://doi.org/10.1007/s00216-006-0362-0 SN - 1618-2642 SN - 1618-2650 VL - 385 IS - 2 SP - 248 EP - 255 PB - Springer CY - Berlin AN - OPUS4-12206 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Weritz, Friederike A1 - Taffe, Alexander A1 - Schaurich, Dieter A1 - Wilsch, Gerd T1 - Visualization of chloride and sulfate ingress into concrete by element distributions and depth profiles determined with laser-induced breakdown spectroscopy (LIBS) T2 - 5th International Essen Workshop "Transport in Concrete - Nanostructure and Macrostructure" (TRANSCON 07), June 11-13, 2007, Essen T2 - 5th International Essen Workshop "Transport in Concrete - Nanostructure and Macrostructure" (TRANSCON 07) CY - Essen, Deutschland DA - 2007-06-11 KW - Laser induced breakdown spectroscopy KW - Concrete KW - Chloride KW - Sulphate KW - Depth profile PY - 2007 SN - 978-3-931681-88-3 SP - 149 EP - 158 PB - Aedificatio Verl. CY - Essen AN - OPUS4-18635 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -