Abstract
Reliability analysis has become important to designs of all kinds of structures, since both international and Japanese standards of structural designs are determined to have their theoretical and practical backgrounds on the reliability analyses. However, to apply reliability analyses to actual structures, statistics such as mean values and standard variations of design variables are needed. Aiming to apply reliability analyses to RC cast-in-place open channels, investigations are conducted for the standard variation of effective depth, which is supposed to be an important design variable in reliability analyses. Thickness of sidewalls and reinforcement coverings in them are measured in RC open channels, and the obtained results are examined statistically. The result showed that the construction accuracy of reinforcement positioning is much inferior to that of side wall thickness, and several cases are found in which construction accuracies are different among sidewalls along the same channel. As the standard variation for effective depth of sidewall of RC open channels, a figure of 10.1mm is proposed as the result of this study.
