الفهرس 
Optimum design of girdersOnly 14 pages are availabe for public view
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Abstract
One of the ways to achieve economy in designing
highway steel bridges is to use composite construction. These
composite plate girders are economical when strength governs
the design because concrete provides a large compression
capacity. Since the rules governing the design of plate girders
are complicated, a trial and error approach is always employed
to find the best solution. However, this traditional method is
time consuming and therefore structural optimization techniques
that employ mathematical programming is used.
In this study, an effective procedure has been developed
for the optimum design of different types of composite girders
(homogeneous, hybrid, stiffened and unstiffened). The
conditions of Egyptian code of practice for steel constructions
and bridges (E. C.P) are considered using the weight of the
girder as the objective function, and the section properties and
strengths as the problem constraints. The design constraints are
defined in both equality and inequality forms. Furthermore, the
dependent and independent variables together with the
nonlinear objective function and nonlinear design constraints
are expressed in a suitable form to use Microsoft Excel Solver
in solution of the optimization problem models .
Design curves for optimum weight and optimum
properties of an unstiffened homogenous, unstiffened hybrid,
stiffened homogenous and stiffened hybrid steel plate girders
are presented.
KEYWORDS. Composite Construction - Plate GirdersHighway
Bridges - Optimization-Mathematical
Programming.