ABSTRACT
ABSTRACT: In this paper, experimental and analytical studies on ultimate strengths of simply supported partial composite beams with compact-section steel girders were conducted. Long-term effects were also considered. Four 6.5 m long steel-concrete composite girder specimens were fabricated. To investigate the effects of creep and shrinkage of concrete slabs on composite beams, long-term behaviors such as the changes of deflections, curvatures, and strains were measured for one year. After 400 days, three specimens, which have different degrees of shear connection, were tested to get the ultimate strengths in positive moment region and another one for negative moment failure. Long-term test results were compared with the analytical results obtained by using the ageadjusted effective modulus method (AEMM). Elastic-plastic finite element analysis considering relative slip between slab and girder was also performed to estimate the theoretical ultimate strengths of the specimens. From the analytical and test results, the effects of long-term behavior of concrete, partial shear connection or interaction and material nonlinearity on the ultimate loads of composite beams were evaluated and discussed.
