Analytical Studies of Full-scale Steel T-stub Connections Using Delicate 3D Finite Element Methods

Abstract

This study presents the development of refined three dimensional (3D) finite element (FE) models with the ability to reliably simulate the mechanical behavior of full-scale bolted T-stub connections. FE models incorporated material nonlinearity, geometric nonlinear behavior, several contact interactions between faying surfaces, and prescribed displacements for generating initial bolt pretension. These FE models were used to compare experimental test results, which verify that advanced FE modeling methods make a notable contribution to reproducing the overall behavior of connections and components accurately, including the moment-rotation curves. In addition, the FE models provide some useful information which is difficult to obtain during physical testing, i.e., the distribution of stress and strain, friction forces between shear faying surfaces, and bolt reaction forces. The validated FE models are also used for additional parametric studies so as to comprehensively understand their response mechanisms. Moreover, the observation of FE analysis results supports the statement that connection models presented herein were designed to reach the yielding of connection components when the structural beam produces its full plastic moment at the plastic hinge.

Analytical Models for Determining Rotational Capacity of Clip-Angle Connections under Seismic Loading

“…Fig. 3 shows the standardized parameters typically used for the mathematical models described in Table 1 [6,7,8,9,[12][13][14][15][16][17][18][19][20].…”

New Bolted End-Plate Connection Design

“…1 are generally referred to as 8 tension bolt type with stiffener and no slip. Reliable welding can be achieved with end plate connections because they are generally fillet welds executed in the shop as compared to complete joint penetration welds executed in the field for traditional full moment welded ones [4][5][6][7][8][9][10][11]. End-plate connections also have advantages such as easy fabrication and fast erection when compared to welded connections.…”

Design and Strength Evaluation of Critical Gusset Plates in the Steel Bridge Using New Load and Resistance Factor Design Methods and Advanced FE Analyses

“…Some of these FE analyses have been utilized to perform parametric studies that provide insight and guidance for structural design, due to the advantage of being easily scalable to model. [13][14][15][16] Despite these merits, the advanced FE models that are made up of 3 dimensional (3D) solid elements incorporating fully nonlinear material properties, geometric nonlinearity, contact interactions, and initial bolt pretension are limited to achieving practical design purposes in massive and complicated structures. It is because they require not only high computational cost but also sophisticated preparation process.…”

“…6(b). The following equations also specified in the AASHTO Specifications are used to evaluate the factored design resistance strength (R rcrw ) according to the slenderness ratio as follows: 13) ..... (14) ..... (15) where, K indicates the effective length factor stipulated in the traditional column buckling equation and E indicates the elastic modulus of the base steel material. Depending on sway condition and buckled shape, the effective length factor for gusset plate design may be taken as a value of 1.2.…”