Investigation of the moment redistribution for steel concrete continuous beams

This study investigates moment redistribution phenomenon for pin ended double-span steel-concrete
continuous composite beams and arise a question about moment redistribution for the continuous
beams subjected to partially distributed or concentrated loading conditions. The overall objective of
the study is to propose a methodology to fulfil the technical gaps adopted by Eurocode-4, which
considers the redistribution for only uniformly load condition. A robust iterative algorithm is
developed to obtain moment-curvature relations of the standard composite cross-sections. Flexural
stiffness-curvature relations of the cross-sections are predicted through the moment-curvature
relations. Flexural stiffness distribution along the composite beams is determined with curvature
compatibility. Fourth order differential load-deflection equation is evaluated with finite difference
solution scheme for continuous beam conditions and variable flexural stiffness along the beam length.
A non-iterative incremental load-deflection algorithm is developed to calculate moment distribution
in continuous beams with variable flexural stiffness. A benchmark example is solved with Eurocode-
4 provisions to validate the developed algorithms. Moment redistribution from hogging (negative)
zone to sagging (positive) zone of uniformly loaded double-span continuous composite beam is
illustrated considering the degree of flexural stiffness degradation in the composite medium. A
question is arisen for moment redistribution in the continuous beams subjected to partially distributed
or concentrated loading conditions.