Safety of Early Age Loaded Reinforced Concrete Members
Keywords:
Construction load, reliability, slabAbstract
This paper examines the effect of construction loads on the safety of reinforced concrete members. A simply supported reinforced concrete slab was considered for the investigation. The probabilistic analysis of time dependent characteristic concrete strength takes into account the slab capacity from casting to maturation. The variation of load was accommodated though a load ratio (dead to live). Adequate review was made on structural reliability analysis using first order reliability method. The focus of the paper was on evaluating the effect of early age loads on the reliability of reinforced concrete members, in which the uncertainties associated with the basic design variables were fully accommodated. First Order Reliability Method was employed though a developed computer program in FORTRAN 77 to accomplish the reliability analysis. It was clearly established that concrete structural members under construction loads has limiting capacity  prior to twenty eighth days after casting, and may lead to dramatic lost of stability of the whole system, if shoring and formwork are removed
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