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

phenomenon will decrease the bolt-force in the bolts closer to the beam-flange and increase the
bolt-forces in the bolts far from the beam-flange, which consequently increases the ultimate
loading capacity of the connection.
2- To enhance connection energy dissipation by reducing the pinching phenomenon in the cyclic
hysteresis behavior of the bolted beam to column connection. Using the circular bolt pattern
configuration reduces the bolt-forces in the bolts closer to beam flange, which delay their
yielding. Thus, connections with a circular bolt pattern sustain pre-tension forces for longer
duration. This means that pinching may be reduced or delayed in connections with a circular bolt
pattern when compared with those with a square bolt pattern.
3- To develop a prediction equation for strength, stiffness, and other related parameters, which
predict the moment-rotation hysteresis behavior of the connection with circular and square bolts
patterns. These parameters are commonly defined by the yield moment, the yielding rotation,
the ultimate moment capacity, and the ultimate rotation.
4- To develop a unified multi-linear hysteresis method to predict the hysteresis behavior of the
extended end-plate connections under cyclic loading for any given geometry.
5- To compare the energy dissipation variation between connections with circular and square bolt
patterns. This is accomplished by comparing the area under the hysteresis outer-loops of each
model, which be defines their energy dissipation characteristics.
6- To conduct a detailed investigation with regard to the end-plate and bolt behavior of connections
with circular and square bolt patterns with different geometric variables.
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