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High thin-walled cold-formed steel purlins of the Z cross section are important elements of large-span steel structures in the construction industry. The present numerical study uses the finite element method to analyse the 300 mm and 350 mm high Z cross sections in-depth. The prepared numerical models are verified and validated at several levels with experiments that have been previously published. Significant agreement between the numerical models and the experimental results regarding Mises stress, proportional strain, failure mode, and force-deformation diagram have been obtained. With the verification, the presented procedure and partial findings can be applied to other similar problems. The results can be used to help research and corporate groups optimise the structural design of cold-formed thin-walled steel structures. [ABSTRACT FROM AUTHOR]

The paper deals with evaluation of possible fatigue damage of existing steel crane structure. It is possible to use the some traditional methods to solve the problem - a concept of fatigue S-N curves (which are mainly used for designing of a new structures) or the procedures based on linear fracture mechanics utilizing the Paris-Erdogan’s law (which are suitable for estimation of remaining lifetime). For the resistance assessment the relevant data of load effects caused by cyclically loaded structure operation are necessary for both concepts. For the prediction of fatigue damage over time, calibration functions for short edge cracks were derived based on the results of the experiment, and the acceptable size of the fatigue crack in damaged structural component under analysis was determined. Using the derived relationships, a stochastic analysis of the selected element was performed and the results are discussed.

The paper is focused on the static analysis of the cone, which is one of the basic shapes used for membrane structures. These structures are specific by their ability to transmit only tensile forces. Pressure forces in the membrane construction may cause unwanted wrinkling of the used textile materials. When designing membranes, one of the variable parameters can be the height of cone and the radius of the circular profile at the top of the cone, which affects the resulting stress and internal forces. This paper aims to analyze the reliability of the cone in terms of the extreme stress and internal forces while maintaining the same ground plan.

The paper presents a general procedure of numerical analysis of the steel structure in case of cyclic loading. The basic recommendations that can be applied to different details, are discussed. The article shows examples of the truss structure loaded with a crane track, but also applicable to other types of constructions. There are basic ideas of the whole process, which is divided into several parts. The beginning of the process is to determine the influence line from the simplified model of the whole structure. A stochastic estimation of the load effect associated with the load history in combination with the influence line is utilized. The complex 3D FEM model for estimation of residual life of the chosen detail is the main result of the analysis.

This paper deals with the use of probabilistic methods in assessing the reliability of the planar truss support structure. Classical Monte Carlo simulation technique was chosen for calculation of failure probability in structural elements and the entire support system under assessment. Numerical calculation was applied in MATLAB software system using the random number generator and parallelization using multi-core processors. The aim of the study was to analyze the usability of MATLAB for probability calculations and probabilistic reliability assessments of load-bearing structures.

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Fatigue crack damage depends on a number of stress range cycles. This is a time factor in the course of reliability for the entire designed service life. Three sizes are important for the characteristics of the propagation of fatigue cracks - initial size, detectable size and acceptable size. The theoretical model of fatigue crack progression can be based on a linear fracture mechanic. Depending on location of an initial crack, the crack may propagate in structural element e.g. from the edge or from the surface. When determining the required degree of reliability, it is possible to specify the time of the first inspection of the construction which will focus on the fatigue damage. Using a conditional probability and Bayesian approach, times for subsequent inspections can be determined. For probabilistic modelling of fatigue crack progression was used the original and new probabilistic method - the Direct Optimized Probabilistic Calculation (“DOProC”), which uses a purely numerical approach without any simulation techniques or approximation approach based on optimized numerical integration.

This contribution is focused on the design analysis of membrane structure and finding an optimal shape of such structure due to the surrounding possibilities with using numerical modeling. The membrane structure is designed for roofing of the experimental stand, which is in the campus of Faculty of Civil Engineering, VSB - Technical University of Ostrava and is currently not protected against unfavorable weather conditions. Design of membrane structures as temporary or permanent roofing has recently become very popular because of its shape variability, very low weight, and possibility of large spans. However, in addition to aesthetic requirements, structural and dispositional requirements are also necessary to consider on the same level during the design. The aim of this paper is to give an overview of the design of the temporary membrane structure starting from the architectural visualization and continuing to deal with structural and dispositional parts of the design using the RFEM software which has special add - on module for nonlinear analysis of membrane structures, RF Form - Finding. [ABSTRACT FROM AUTHOR]

This article is aimed at current methods of calculating wind loads in structural engineering for construction, where these values cannot be clearly established by standard procedures. A suitable tool for these cases can be, for example, computational software for numerical simulation of wind flow around the structure, which allows the results of the simulation to be directly implemented to the numerical model as a load. The article introduces software for numerical simulation of wind flow and determination of induced force effects on the object of the high-rise building. The resultant force determined by the software was compared with a simplified calculation carried out according to the currently valid standards for determination the actions of wind on the structure. [ABSTRACT FROM AUTHOR]