Cyclic Testing and Parametric Study of Bolted Beam-height Adjustable Steel Beam-to-columnConnections

摘要

A kind of bolted beam-height adjustable beam-to-column connections (BHA connections) is proposed for moment-resisting steel frames. It is applicable when the height of beams change in small ranges. A BHA connection is composed of a T-shaped connector, an L-shaped connector with ellipse-type blot holes and bolts. A cyclic test on four full-scaled subassemblies and a series of numerical parametric analyses of BHA connections were conducted to study their mechanical performance. The test results show that the BHA connections with properly stiffened L-shaped connectors possessed good hysteretic properties, stabile secant stiffness and load-carrying capacity degradation and excellent energy dissipation capacity. And the effect of connector slippage and beam web eccentricity was negligible. It can be found in the parametric study that the flange thickness of T-shaped connectors played a pivotal role both in the load-carrying capacity and elastic stiffness of BHA connections, and the elastic stiffness was also affected by the thickness of T-shaped connector webs, L-shaped connector flanges and webs, and column stiffeners. Moreover, the numerical results also demonstrated that the column stiffeners in joint regions could improve the efficiency of load transfer between beams and columns. This kind of connections can be used to assemble steel frames expediently.