A computer method for elastic-plastic continuous beams with rotation constraints is proposed. Such structures belong to a particular class of slackened systems, i.e. systems with gaps at structural joints. In order to calculate both the structure and mechanism a concept of the finite element with elastic rotation supports is used in the computer program. The uniqueness of solutions makes it possible to use a pure elastic analysis with some additional constraints superimposed on state variables. It allows us to avoid the time-consuming mathematical programming methods.
Several examples illustrate the behaviour of beams under multiparameter loads.
The work presents the characteristic features of slackened structural systems. M. Kaminski and O. Gajl. Numerical modelling of fibre composites with random-elastic components. The displacement and the stress random fields have been analysed for various contents of a fibre periodicity cell of such a composite, and for different coefficients of variation of the Young modulus of both phases. Extended finite element homework.