What do you think if you consider the notion „mechanics“? Do you think of gears, coupled cranks consisting of rods clamped at rotating propulsions? Today mechanics does not mainly treat these more construction oriented ideas. Mechanics has much more facets. It is much more demanding and lives from interdisciplinarity to engineers, mathematicians, physicists, and computer scientists. Beyond the partial fields of fracture mechanics, dynamics of machines, structural mechanics, environmental mechanics and fluid mechanics, solid mechanics, which is, in this context, considered to be equivalent to continuum mechanics, represents one of the largest research disciplines. Within the field of solid mechanics, we distinguish between experimental mechanics, theory of materials, i.e. constitutive modeling of material properties using mathematical models, and computational mechanics. Theory of materials consists of a broad scientifical field starting from purely mathematical modeling up to the concrete physical modeling of all kinds of materials. The more traditional aspects of modeling the three-dimensional material behavior of solids under various loading processes, where one not only treats metals, plastics of elastomers, but also soils, concrete or wood, are today coupled with thermal, electrical, magnetic and chemical influences and are extended to micro-physical considerations. Moreover, biomechanics of animal and human tissues is an extremely expanded field of research.The chair of solid mechanics at the Clausthal University of Technology treats the physical modeling of various materials, which undergo small and finite strains effects. These problems occur in metal forming, elastomer and plastics technology. The models are based on experimental observations of tensile, compression and torsion tests under varying thermal conditions, see Fig.1.

In this context two important aspects occur: first, the constitutive models have material parameters, which have to be adapted/calibrated to the experiments. This is coupled with non-linear optimization algorithms. Second, the constitutive models have to be implemented into commercial and in-house finite element programs, so that any work tool can be realistically simulated.

Fig. 2. shows the five columns of the chair of solid mechanics (experiment, constitutive modeling, simulation, structural computation, and parameter identification). This is embedded in the research area of verification and validation. Verification means the development of numerical and analytical methods to proof the correctness of the solution, i.e. both the implementation into the finite element programs and the solution itself, implying the development of highly accurate and, accordingly, efficient methods. In the case of validation the numerical and physical models have to be compared with the experimental (and/or real) structural behavior. However, the quality, commonly termed by “good” or “bad”, has to be specified more precisely by a metric in advance. In this research area several works have been done in the direction of material parameter identification, the conduction of experiments, constitutive modeling, and new developments in adaptive time-integration procedure using finite elements.

The lab of solid mechanics, the PC-pool shown in Fig. 3, as well as the research assistants and the division’s staff support by their work the goals of the team