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

edition of AISC steel design manual [53]. They utilized a 2-D constant strain triangle element and a 3-D
eight-node brick element to determine adequate correlation between the results. The finite element
models were analyzed under bolt pre-tension, half service load, and full service load. The results from
the 2-D model were used to find the correlation between the 3-D models and to predict the overall
behavior of the connection. According to this research, because of the time involved in programming, as
well as computational time it was not feasible to conduct a 3-D analysis on the end-plate connections
using the technology of the time.
To obtain a reasonable results from the finite element analysis, Krishnamurty et al. [50][51][52] made
several simplifying assumptions. The 3-D models were developed based on a constant strain triangle
and eight-node subparametric brick elements. Bolt heads were omitted, and the bolts were assumed to
have a rectangular shank with similar cross section as rounded bolts. No “contact element” algorithm
was used to model the contacts or constrains. The bolts were assumed to be in tension and the effective
square area of the compression flange was assumed to be compressed against the column flange.
Some seven correlation-factors between the 2-D and 3-D models were introduced using the results
obtained from the numerical analysis.
Kukreti et al. [54] presented the results of their investigation conducted on the behavior of the
stiffened moment end-plate with two rows of bolts inside and outside the beam tension flange. Finite
element was used to model the tension flange. For simplification, the tension flange and the end-pate at
the tension flange was assumed to have similar behavior as a stiffened T-Stub (tee-hanger). They also
conducted a parametric analysis to develop an empirical equation to predict the behavior of the end-
plate connections.
Kukreti et al. [55] utilized the finite element modeling to develop an equation to characterize the
behavior of the extended stiffened end-plate connections that can be used for predicting the heavier of
the beams used in steel building frames. The regression analysis performed on the data collected leads
to an equation which predicts the end-plate strength, end-plate stiffness, and the bolt forces. The design
methodology was outlined using the prediction equations. The results obtained from the prediction
equation were validated by the experimental results.
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