Tohid Ghanbari Ghazijahani

Bending Experiments on Thin Cylindrical Shells

Cylindrical shell structures are highly susceptible to buckling phenomena when they experience compressive stress. In fact, there are few experimental researches that give the real behavior of a cylindrical shell submitted to pure bending, especially thin shells. This is due to the difficulty of pure bending applying to such thin shells and that such structures behavior under bending is frequently considered rather similar to pure compression. This chapter describes an experimental investigation of a procedure including a system for applying pure bending to cylindrical shells with radius to thickness ratio equals 155. The instrumentation consists of a new loading system in which the pure bending is applied using concentrated loads at the ends of the test model. Ultimately, the critical values for moments as well as buckling modes were compared with finite element (FE) results.

Experiments on Dented Steel Tubes under Bending

Steel tubular sections are extensively found in many kinds of civil and mechanical engineering structures such as columns and bracing elements, offshore industry, bridge elements, etc. Due to the extensive usage, a considerable amount of research has been carried out on such structural members. Although many studies focused on the bending stability of steel members, very little research can be found on the effect of surface defects, such as dent imperfection, on the bending behavior of such tubular members. This research aimed to evaluate the effect of dent-shaped defects on the flexural capacity of CHS members. The data obtained in this paper can be applied to evaluate the capacity of large scale CHS members with similar D/t ratio when a dent is formed on the tubes during the service life of such members. An interrelation between the capacity and the details of the dent, i.e. size and position of the dent, was proposed.

NUMERICAL STUDY ON STEEL SHEAR WALLS WITH SINUSOIDAL CORRUGATED PLATES

Over the past decades a growing demand and interest has stimulated many researchers to investigate different aspects of steel plate shear walls (SPSWs). The structural performance of steel shear walls with sinusoidal corrugated plate infills is investigated in this study. Finite element (FE) analysis was adopted using ANSYS software, wherein flat and corrugatedshear walls - with different thicknesses, various corrugation numbers and angles - were modeled under monotonic and cyclic loads. Results and findings of this study indicate that geometrical variations developed through corrugation can be effective on the capacity, rigidity, and post-yielding responses of such corrugated-web lateral force-resisting systems. In addition, proper design and detailing can result in desirable structural behavior and seismic performance of SPSWs with sinusoidal corrugated infill plates.