This paper presents methods for estimating the load-bearing capacity of reinforced concrete (RC) structures subjected to impact loading by rigid and deformable projectiles. For rigid projectiles, selected empirical approaches for determining the perforation thickness are examined together with their ranges of applicability. An energy-based evaluation also allows test results with measured residual velocities to be included. For the tests considered, the extended RCC-CW approach provides the smallest overall deviations from the experimental results, whereas the CEA-EDF-Fullard approach generally yields conservative predictions. For deformable projectiles, a mean impact force derived from the impact impulse is compared with the punching shear resistance of the RC slab. Comparison with experimental test results shows that the observed failure modes are correctly predicted. Due to the limited number of required input parameters, the approaches presented are particularly well-suited for preliminary design and plausibility checks.
The Quality Certification for Sustainable Buildings (QNG) is an assessment tool developed in Germany to systematically record and document the sustainability of construction projects. The QNG is based on a holistic view of building quality and takes into account ecological, economic, and social dimensions. The applicability of life cycle assessment was tested using an exemplary reference building in solid construction for residential use. For this purpose, a variant study was carried out in which different heating and ceiling systems were taken into account. To determine the material quantities and energy requirements during the use phase, the respective building structures were statically measured and the necessary thermal insulation certificates were prepared for all heating systems considered. The results were analyzed with regard to the proportions of the various life cycle phases in the total emissions. In addition, a detailed evaluation of the composition of the so-called "gray energy" was carried out. Finally, the extent to which the QNG is also a suitable label for sustainable construction for solid construction buildings was examined.
Damage diagnosis is a fundamental task in structural health monitoring (SHM). In this study, a statistical, sensitivity-based localisation approach is employed, where a residual vector is computed from vibration measurements in reference and damaged states. The residual is evaluated using statistical hypothesis tests along change directions defined by sensitivities with respect to structural parameters of the finite element (FE) model. Elements associated with statistically significant test results are identified as damaged. The use of an FE-model enables application to a wide range of structures while reducing accuracy requirements, as no model updating is needed. Although the theoretical framework is well established, experimental validations remain limited. This work aims to improve the robustness of the approach for practical applications by proposing preliminary strategies for selecting key input parameters. The method is validated on a steel beam structure, where stiffness changes are introduced by attaching plate components at different locations. The approach is evaluated using both simulated acceleration data and experimental measurements.
This paper deals with the experimental and numerical analysis of bentonite-modified bedding materials for underground power cables. Efficient dissipation of cable heat into the surrounding soil is essential to ensure that underground power cables operate efficiently and have a long lifespan. This requires bedding materials with high thermal conductivity, which in soil primarily depends on the water content. The pursued approach involves mixing soil with bentonite. The aim is to assess whether the addition of bentonite can improve the water-retention of the soil and reduce thermally induced drying without adversely affecting thermal conductivity. The thermal conductivities of two types of soil for different water contents, degrees of compaction and bentonite contents are determined. In addition, simple cyclic heating tests are performed to assess the drying behavior of the bentonite-amended soils. Furthermore, the temperature fields during the drying test are numerically simulated and validated with the experimental results.
The draft edition 2026/1 of the Model Administrative Regulation for Technical Building Rules (MVV TB) [1] marks an important milestone for earthquake design in Germany. The draft proposes replacing DIN 4149 [2] with the provisions of DIN EN 1998-1 [3] and DIN EN 1998-5 [5] as well as their national annexes [4, 6]. This will bring the building regulations for earthquake design into line with the current state of the technical standards. The specific introduction will then take place via the respective state building regulations.
