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*[email protected]
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Exact Method in Design of Circular Base Plate under Large
Eccentric Loads
M. Naghipour*, M. Delvarani and N. Jafari Mobin
Babol University of Technology, Department of Civil Eng
Abstract Circular base plates are commonly used for pipe
columns, such as pylons in cabled-stayed bridges, lighting poles
and electric power line posts. Against rectangular base plates, an
exact method has not been presented about design of circular base
plates in the classified and well-documented form. Therefore, this
paper by expression of mathematic formulas describes on exact
method to design these plates which use of this method requires an
iteration approach to solve the equilibrium moment equation. Then
it compares by presented graphs obtained designing results from
exact and existing method [1], in return for different design
parameters and demonstrates safe limits to use of approximate
method. The results show that approximate method commonly will not
be safe and can demonstrate reasonable results under specified
conditions. Whereas exact method has been presented in this paper
is safe and replies reasonably under any conditions.
Keywords Circular Base plate, Eccentric loads, Equilibrium
equations, Exact method.
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1. Dajin, L., Circular Base Plates with Large Eccentric Loads,
Practice Periodical on Structural Design and Construction, ASCE, J.
of Structural Eng., (MAY 2004)
2. American Institute of Steel Construction (AISC). (2005)
Chicago.
3. Swokowski, E. W., Calculus with Analytic Geometry, Alternate
Ed., Prindle, Weber and Schmidt, Boston (1983).
4. Young, W. C. Roarks formulas for stress and strain, 6th Ed.,
McGraw-Hill New York (1989).
5. American Institute of Steel Construction (AISC). Manual of
steel construction-ASD, 9th Ed. Chicago (1989).
