Characterisation of dust exposure during the processing of carbon concrete
In the framework of a thesis, the experimental quantification and identification of inhalative dust exposure released by mechanic working processes on concrete reinforced with carbon fibre was documented. The focus is on variants of carbon concrete which were developed in the framework of the “C3-Project” at the TU Dresden. In order to simulate common processing and dismantling procedures for concrete specimens, experimental examinations were carried out within the scope of the project. The characterisation of dust release in the sense of workspace measurements is the main focus of this work. By using common personal sampling systems for hazardous substances (PGP), dusts were collected at a distance of 1 m to the source of exposure and then evaluated. Dust mass concentrations were determined for alveolar dust and inhalable dusts by weighing. The fibre number concentrations for anorganic and organic fibre dusts were determined by means of a scanning electron microscope (SEM) and an energy dispersive X-ray spectrometer (EDS). The comparison of the measured values for all working procedures showed that especially sawing and grinding processes lead to major dust exposures. An investigation of the concrete’s compressive strength with regard to dust exposure showed that processing high-strength concrete leads to higher concentrations for the respective working procedure compared to processing standard concrete. Organic WHO fibres could not definitely be identified as carbon fibres. All things considered, no increased potential danger originates from organic fibres due to the compliance with the assessment standard for fibre dusts in all examinations.
C3-Carbon Concrete Composite is being supported as one of ten projects in the programme of the Federal Ministry of Education and Research “Twenty20 – Partnership for Innovation” in the framework of “Operation Region” with approx. 45 million euros. Additionally, about 23 million euros come from the partner´s capitals. With this, the partners involved in these ten projects have above 65 million euros research funds for this topic at their disposal.