Vibration And Stress Analysis of Multi-story Steel Structure with and without crack

Abstract

Modal characteristics of buildings and machinery are essential for predicting dynamic behavior throughout operational phases. To avoid any catastrophic collapse, it is essential to identify the dynamic properties and optimize the structure during the design process. In order to throw some insight on the equivalent stresses created in the structure using numerical methods, the study will concentrate on the modal characteristics of steel structures both computationally and experimentally. Not only have the modal parameters been established, but also the experimental confirmation of the findings. This will enable precise numerical analysis of high-rise steel buildings without spending money on expensive trials. Moreover, the purpose of using I-beam instead of rectangular or square shaped beam has been studied. Through simulation in ANSYS, the mode shapes and natural frequencies of the 10-story building have been determined for both loaded and unloaded situations. The first six modes were taken out since it has been seen that they have the most effects on the structure during dynamic loading conditions like earthquakes. In order to determine the relative stresses that generated in the 10-story unloaded structure under various mode shapes and natural frequencies, Von Mises stress analysis has also been carried out. The diverse mode forms and natural frequencies have been discovered from the various stress conditions of the structure. The mode shapes and natural frequencies alter along with the loads from floor to floor. The natural frequencies and forms are very different from the unloaded structure. The research is innovative in that it compared the modal characteristics under various loading circumstances to those under an unloaded structure. Furthermore, this study will examine how cracks affect the dynamic behavior and stress distribution of steel structures. The structure is modeled using the finite element method, and the outcomes are evaluated against available experimental data. The study shows that the presence of a fracture has a substantial impact on the structure's dynamic behavior and raises the stress concentration. The findings imply that a break can both lower the structure's inherent frequency and raise the vibration's amplitude. The results of this study can be extremely helpful in designing and maintaining steel structures, especially when determining how safe and long-lasting they are.