Noise barriers (LSW) consisting of a facing layer of lightweight aggregate concrete (HPLB) in monolithic bond with a structurally sealed reinforced concrete supporting shell have suffered various types of damage in the recent past. The damage mainly occurred locally in the form of cracks, spalling and weathering in the HPLB of the facing shell, and in some cases the HPLB detached from the supporting shell and fell off.
The aim of the research project is to comprehensively and systematically analyze the causes and development mechanisms of such damage. Extensive investigations on affected LSW will identify the damage-relevant material properties as well as the structural and exposure-dependent influencing parameters. Within the scope of the investigations, suitable test methods are determined and - if necessary - modified in such a way that the damage-relevant material properties of the HPLB can be quantified and evaluated accurately. Based on the results, material-specific requirements for HPLB for facing shells of LSW are determined and adequate concepts for quality assurance are developed. Based on this, systematic material studies will be carried out on the influence of the composition of HPLB on the damage-relevant material properties. Different HPLB are included, which are typically used for LSW and partly differ significantly in their composition.
Finally, concrete-technological as well as constructive measures for damage-free new buildings and a target-oriented repair are derived. Suitable repair procedures are also developed for the repair of LSW. Furthermore, the measures for the new construction and the repair of LSW will be evaluated with regard to their practicability. Finally, the findings of the research project will be used to formulate text proposals for inclusion in the relevant regulations.