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Ph.D.
(Engineering & Technology)
DESIGN AND OPTIMIZATION OF STIFFENED BEAM WITH
VARIOUS LOADING CONDITIONS

Ph.D. Scholar : Patel Dhavalkumar Punamchand
Research Supervisor : Dr. Bhavesh P. Patel

Regi. No.: 14146051003
Abstract :
Offshore, bridges, steel structural, and heavy-duty equipment all use hollow cantilever
beams. The great challenge for design engineers is to provide a better robust design of
cantilever beams that can withstand applied load with optimised design parameters.
According to the literature review, the strengthening of a beam or plate can be
accomplished by providing transversal or/and longitudinal stiffeners that can withstand
post buckling and lateral buckling moments. Thus, it is not sufficient for designers to
provide only a better design of a part or component with the minimum weight and cost
while ensuring optimum reliability and keeping the design secure in all loading conditions.
The behaviour of beam strength is influenced by a variety of factors such as the number
of stiffeners, their location, and their dimensional properties. The slope and deflection
equations of a uniform cross-sectional hollow rectangular cantilever beam with stiffeners
subjected to the concentrated load applied at the free end as well as uniformly distributed
load (UDL) and their combination are derived and calculated mathematically using Mohr's
moment area method in the presented work. Finite Element Analysis (FEA) is used to
validate the results under known load and boundary conditions. The results are identical,
demonstrating that the mathematical formulation can assist the design engineer in
predicting the deflection of a cantilever beam under known loading and boundary
conditions.

The bending moment and stress equations of a uniform cross-sectional hollow
rectangular cantilever beam with stiffeners subjected to combined concentrated and
uniformly distributed load (UDL) is derived using classical beam theory and the beam
discretization performed using Mohr's Moment Area Method (MMAM). Finite Element
Analysis (FEA) is used to validate the results under known load and boundary conditions.
The results demonstrate that the mathematical formulation can assist the design
engineer in predicting the stresses developed in the cantilever beam under known loading
and boundary conditions. Design optimization technique was used to investigate the
effect of cross-sectional dimensions such as height, cross-section thickness of beam; on
beam weight in order to withstand the exerted load yet with minimum material keeping
the total equivalent stress just below the maximum yield stress, (σy< 225 MPa) and
deflection of the beam below the limiting condition as per Eurocode-3 (11.11 mm). It
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