@article{BucherSchorling1997, author = {Bucher, Christian and Schorling, York}, title = {SLang - the Structural Language : Solving Nonlinear and Stochastic Problems in Structural Mechanics}, doi = {10.25643/bauhaus-universitaet.495}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-4957}, year = {1997}, abstract = {Recent developments in structural mechanics indicate an increasing need of numerical methods to deal with stochasticity. This process started with the modeling of loading uncertainties. More recently, also system uncertainty, such as physical or geometrical imperfections are modeled in probabilistic terms. Clearly, this task requires close connenction of structural modeling with probabilistic modeling. Nonlinear effects are essential for a realistic description of the structural behavior. Since modern structural analysis relies quite heavily on the Finite Element Method, it seems to be quite reasonable to base stochastic structural analysis on this method. Commercially available software packages can cover deterministic structural analysis in a very wide range. However, the applicability of these packages to stochastic problems is rather limited. On the other hand, there is a number of highly specialized programs for probabilistic or reliability problems which can be used only in connection with rather simplistic structural models. In principle, there is the possibility to combine both kinds of software in order to achieve the goal. The major difficulty which then arises in practical computation is to define the most suitable way of transferring data between the programs. In order to circumvent these problems, the software package SLang (Structural Language) has been developed. SLang is a command interpreter which acts on a set of relatively complex commands. Each command takes input from and gives output to simple data structures (data objects), such as vectors and matrices. All commands communicate via these data objects which are stored in memory or on disk. The paper will show applications to structural engineering problems, in particular failure analysis of frames and shell structures with random loads and random imperfections. Both geometrical and physical nonlinearities are taken into account.}, subject = {Baustatik}, language = {en} } @phdthesis{Schorling1997, author = {Schorling, York}, title = {Beitrag zur Stabilit{\"a}tsuntersuchung von Strukturen mit r{\"a}umlich korrelierten geometrischen Imperfektionen}, doi = {10.25643/bauhaus-universitaet.29}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20040216-317}, school = {Bauhaus-Universit{\"a}t Weimar}, year = {1997}, abstract = {F{\"u}r geometrisch imperfekte Strukturen wird die Versagenswahrscheinlichkeit bez{\"u}glich Stabilit{\"a}tskriterien bestimmt. Eine probabilistische Beschreibung der geometrischen Imperfektionen erfolgt mit skalaren ortsdiskretisierten Zufallsfeldern. Die Stabilit{\"a}tsberechnungen werden mit der Finite Elemente Methode durchgef{\"u}hrt. Ausgangspunkt der Berechnung ist eine systematische Formulierung probabilistisch gewichteter Imperfektionsformen durch eine Eigenwertzerlegung der Kovarianzmatrix. Wenn mit einer strukturmechanisch orientierten Sensitivit{\"a}tsanalyse ein Unterraum zur n{\"a}herungsweisen Beschreibung des probabilistischen Strukturverhaltens gefunden wird, kann die Versagenswahrscheinlichkeit numerisch sehr effizient durch ein Interaktionsmodell bestimmt werden. Es zeigte sich, daß dies genau dann m{\"o}glich ist, wenn die Beulform merklich im Imperfektionsfeld enthalten ist. Die Imperfektionsform am Bemessungspunkt entspricht dann, unabh{\"a}ngig vom Lastniveau, gerade der Beulform. Wenn die Beulform im Imperfektionsfeld einen untergeordneten Beitrag liefert, erscheint eine Reduktion des stochastischen Problems auf wenige Zufallsvariablen dagegen nicht m{\"o}glich.}, subject = {Tragwerk}, language = {de} }