Design of Quad Elements – The Baumann Method
In this video, György Schmidt explains the design of quad elements according to the Baumann method (Der Bauingenieur 47 (1972), pages 367-377). The method has similarities to the Sandwich-Model described in EN-1992-2 Annex LL.
In reinforced concrete surface structures, the main tensile stresses shall be absorbed by a network of reinforcing units, which may differ from the direction of the principal stresses.
A prerequisite for the design of such a reinforcement network is the knowledge of the inner force state, which is set for given internal forces in a cracked disc or plate element. The determination of this state of force is generally a statically indeterminate task.
Applying an idea first put forward by H. Kupfer 1962, this approach introduces the direction of the concrete compressive force stiffening the reinforcement mesh as statically indeterminate and determines it with the help of the law of the minimum of deformation work.
The size of the shear force to be absorbed by the concrete is determined in a similar manner.
In addition to the stiffness of reinforcement and concrete, the stiffness of the interlocking and anchoring of the crack surfaces is also taken into account.
The theoretical approaches are compared with the results of the tests carried out by R. Lenschow 1966 and J. Peter 1964 on plates and discs made of reinforced concrete.
This is followed by a critique of existing theories and design methods for mesh reinforcement.
First, however, the conclusions that arise for the practical design of orthogonal as well as two- and three-layered reinforcement meshes in any direction are described.
Watch the video and learn the principles about the Baumann method explained step by step on a single quad element. Furthermore, a comparison of the results calculated with SOFiSTiK (BEMESS) is shown.
Download the example file (text input file + pdf)
This video is part of a series, and I recommend to watch the following too.