Method of material quality estimation with usage of multifractal formalism

Feasibility of application of multifractal theory for evaluation of materials mechanical properties, cast iron in particular, has been considered. The proposed method enables evaluation of mechanical properties of materials based on determination of their sensitivity to dimensions of structure elements from the multifractal Renyi spectrum. Sensitivity of cast iron ultimate strength to informational dimension of carbides, ultimate bending strength to fractal dimension of carbides, impact strength to correlation dimension of carbides and hardness to fractal dimension of graphite have been determined. Fractal prediction models of quality characteristics of cast iron based on the analysis of the following its structure elements (carbides and graphite) have been received

Analysis of Damaged Concrete Columns of Circular Cross-Section

The article shows the development of analytical method for the calculation of damaged reinforced concrete columns of circular cross-section. The theory and the basic settings for the calculation are based on European Eurocode standards. The paper describes the development of method, from basic assumptions (most important assumption arises in condition of the external and internal forces plain parallelism) to the final setting of five equations with five unknowns for further solving using Newton-Raphson method. The final results (via the input and resolved parameters) are given in the height of the compressed area x, the stresses in the reinforcement bars σsi and finally, in the current bearing capacity of damaged rc section N