Comparison of STM’s reliability system on the example of selected element

Abstract

This paper presents optimization of the reliability system for different Strut and Tie models of beams loaded with a torsional and bending moment. In this paper, three STMs depending on the angle of diagonal strut were compared. The presented beam models have a serial system reliability. In the analyses, the full correlation of the top chord of truss - upper reinforcement, full correlation of bottom chord of truss - compression concrete, full correlation of members mapping individual stirrups and concrete in diagonals between stirrups. Estimation of the reliability of the adopted structures was carried out in a software package of Strurel. The variables of concrete, and steel strength as well as concentrated load magnitude were described by a mean value, a standard deviation and a type of distribution. Summing up the results of the analysis, it was noted, that methods for reliability estimation using information about the model’s reliability structure are an excellent alternative to time consuming simulation methods. These methods allow not only to estimate the reliability of the structure, but also to determine the impact of individual members on the reliability of the entire element.

Keywords

• strut and tie method
• reliability system
• serial structure
• reinforced concrete beam
• torsion