Document Type : Research Paper
Authors
1 Civil Engineering Department, AL- ESRAA university collage .Baghdad, Iraq
2 Civil Engineering Department, University of Technology. Baghdad, Iraq
3 Civil Engineering Department, University of Technology. Baghdad
Abstract
This study presents an experimental approach to investigate the structural behavior of normal and moderately high strength Self Compacted Concrete (SCC) voided slab strips under repeated loading system. The experiments were carried out on eight one-way simply supported slabs. Four of them have been tested under two types of repeated loading regime. The required number of cycles of the first load pattern (R1) to achieve permanent damage in the slab is more than 40 cycles, while the second type of repeated loading regime (R2) requires more than 20 cycles to achieve complete damage in the slab for the selected loading scheme. The remaining four additional slabs were tested under monotonically increasing loads. The loading techniques have been applied under the displacement control scheme. The experimental results show that for moderately thick reinforced SCC one way slab having (3 voids, dia. =75mm) under repeated load R1, the ultimate load is reduced by about 10% relative to the reference solid. In this research, the number of cycles required to achieve permanent damage is decreased by about 7% and the mid-span deflection at ultimate load is increased by about 3.4% relative to the reference solid slab. The ultimate load for slab having (3 voids, dia. =75mm) under repeated load R2 is decreased by about 6%, the deflection at ultimate load and the number of cycles are decreased by about 6.1%and 16.7% respectively concerning SCC reference solid slab.
Keywords
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