INTEGRAL CHARACTERISTICS OF RIGIDITY OF COMPOSITE PLATES MADE OF MATERIALS WITH STRENGTH DIFFERENTIAL (SD) EFFECT
Composite plates are widely used in modern construction. Layers are often made of multimodulus materials in the already existing multi-layer constructions. Steel, special cast iron, graphite, plexiglas, natural soils, timber, ice, concrete and other materials possess multimodulus qualities. The layers are linked with elastic-compliance bonds; transverse bracing (cross section bracing) is absolutely rigid. It is vitally important to take into consideration the rigidity of interlayer connections and multimodulus qualities of separate layers to solve the task of defining the stress-strained state of such constructions. It is necessary to create new methods of calculation of constructions made of such materials and to enhance existing ones. The authors consider the bending theory of composite multi-layer plates whose layers are made of multimodulus materials. Multimodulus qualities are connected with the position of main platforms. To determine the integral rigidity characteristics in the X–Y coordinate system, the transition from the compliance matrix (flexibility matrix) in the coordinate system of the main platforms is accomplished through the transition to the matrix written in the Cartesian coordinate system. As being different from other authors, we suggest performing this transition not through the transformation of the stress component but through the transformation of the compliance matrix (flexibility matrix).