Date of Graduation

12-2018

Document Type

Thesis

Degree Name

Master of Science in Civil Engineering (MSCE)

Degree Level

Graduate

Department

Civil Engineering

Advisor/Mentor

Gary Prinz

Committee Member

Micah Hale

Second Committee Member

Cameron Murray

Keywords

Civil Engineering, Moment Connection, Seismic Design, Steel, Stiffener, Structural Engineering

Abstract

Beam-to-column connections in structural steel buildings may have varying degrees of rotational restraint and varying degrees of moment transfer. In fully restrained moment connections, shear is typically transferred through the beam web, while the moment is mostly transferred through the beam flanges which create tension/compression force couples. Column sections that are incapable of resisting these flange forces are often retrofitted with continuity plates within the connection region to improve capacity. In cases of unequal beam depths on either side of the column, an eccentricity between the framed-in beam flange and continuity plate may be required; however, limited research exists to provide guidance on an acceptable level of eccentricity. This thesis describes a parametric finite element investigation into the performance of beam-to-column moment connections having unequal beam depths and eccentric continuity plate detailing. A total of 12 detailed finite element analyses considering two column sections (W14x132 and W21x147 sections) and six levels of connection eccentricity (ranging from 0 to 6 in.) were considered. Modeling techniques considered for the parametric investigation were validated against experiments performed from the literature. Increasing the level of eccentricity between the beam flange and continuity plate resulted in decreased continuity plate participation; however, unlike current code recommendations, noticeable participation (up to 10% additional flange capacity for a W14x132 column) was observed for eccentricities up to 4 in. A new design equation for determining beam-to-column connection capacities for configurations having eccentricities is proposed.

COinS