ON THE EFFECTS OF CIRCULAR BOLT PATTERNS ON THE ...

plate moment connection can be use in seismic force resisting moment frames. He suggested a strong
column, strong connection and weak beam design philosophy should be utilized. He presented a unified
method for the design of eight extended end-plate moment connection configuration subjected to
cyclic/seismic loading. The design procedure used yield line theory to predict the end-plate and column
flange strength. The bolt forces are determined using the simplified method developed by Brogsmiller
[13]. Results of ninety end-plate moment connection tests used to evaluate the unified design method.
Good correlation with the experimental results was obtained using the unified design method.
Shi et al. [41][42] studied eight full-scale structural steel beam-to-column end-plate moment
connection under earthquake loading in order to investigate the influences on the connection moment
capacity, rotational stiffness, rotational capacity and hysteretic curves. He concluded the end-plate
connection extended on both sides can improved the strength, joint rotational stiffness, ductility and
energy dissipation capacity required for use in seismic force moment resisting frames. The results
indicate that the energy dissipation capacity of the connections with flush end-plate degrades
significantly due to the pinching phenomena in the hysteretic loop. These connections are not
recommended to use in seismic steel frames.
2.3 Bolt Design
There has been a great deal of research conducted on the behavior of the bolts utilizes within steel
moment resisting bolted connections. When bolted T-stubs or end-plate connections are subjected to
tension, prying forces develop, resulting in an increase of the bolt force beyond the magnitude that might
be expected from the applied external tension. Since the force increase within the bolt due to the prying
action might be considerable, this important issue needs to be address accordingly in the design
procedures. Investigating the prying force and predicting the possible prying forces induce within the
end-plate was the primary focus of many of the past studies. Prying force is a function of end-plate and
column flange thickness, as well as the bolt diameter. Many researchers proposed the method to predict
the point of action of the prying force. The majority of the bolt-force prediction methods were developed
using an analogy between the end-plate connection and an equivalent T-Stubs in tension.
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