Aleksander Kozłowski

Rotation Capacity of Bolted Flush End-Plate Stiffened Beam-to-Column Connection

Abstract One of the flexibility parameters of semi-rigid joints is rotation capacity. Plastic rotation capacity is especially important in plastic design of framed structures. Current design codes, including Eurocode 3, do not posses procedures enabling designers to obtain value of rotation capacity. In the paper the calculation procedure of the rotation capacity for stiffened bolted flush end-plate beam-to-column connections has been proposed. Theory of experiment design was applied with the use of Hartley’s PS/DS-P:Ha3 plan. The analysis was performed with the use of finite element method (ANSYS), based on the numerical experiment plan. The determination of maximal rotation angle was carried out with the use of regression analysis. The main variables analyzed in parametric study were: pitch of the bolt “w” (120-180 mm), the distance between the bolt axis and the beam upper edge cg1 (50-90 mm) and the thickness of the end-plate tp (10-20 mm). Power function was proposed to describe available rotation capacity of the joint. Influence of the particular components on the rotation capacity was also investigated. In the paper a general procedure for determination of rotation capacity was proposed.

9.4 – Finite Element Modelling of Fillet Weld Connections

The paper describes the finite element modelling method employed to analyse welded connections. The strength phenomena of fillet welds is based on ductile crack initiation and propagation, so finite element model should include proper modelling of stress-strain relationship, including hardening and softening effects, incorporation of geometrical non-linearity and different material models for base and weld metals and also for heat affected zone. The occurrence of large plastic strains requires the use of the true stress-strain relationship. Non-linear stress-strain curve gives possibility to model local yielding and redistribution of stresses. “Element dead” option available in the FE programs traces initiation and propagation of ductile crack in these places, where ductility of welds is exhausted.