2022 Volume 78 Issue 1 Pages 13-29
Cracks at the outer surface of the web or the bottom flange of a pretensioned PC hollow slab girder, which often develop axially along the PC bars, are investigated by applying a multi-scale analysis coupled with material and structural behavior. Such cracks are generally considered to be caused by steel corrosion, alkali-silica reaction, insufficient cover depth, etc. This study, however, shows that even with standard design and materials, careful curing and construction, cracks may appear a decade or two later in service due to seasonal variations in temperature and humidity. Sensitivity analyses under different environmental conditions are also conducted to investigate the causes of cracking, and it is confirmed that the cracks have little influence on load carrying capacity of the PC girder. Based on the analytical results, suggestions for future countermeasures are also made.
