Structural resistance factors for shear loading in drilled shafts with minor flaws based on experimental study

An experimental study was performed to assess the reduction in shear capacity of model drilled shafts having minor flaws, in the form of voids or soil inclusions occupying 15 per cent of the cross-sectional area of the shaft, mispositioned reinforcing steel and corroded reinforcing steel. Such flaws are often produced in construction but either go undetected by NDE or appear as uncertain anomalies on NDE records. Resources did not permit performing large numbers of tests sufficient to investigate the effect of the probability distributions of these factors; however, selected tests were sufficient to develop a general understanding of the phenomena involved and to suggest provisional values of resistance factors to account for the effect on shearing resistance of unknown construction flaws.

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