An experimental study was conducted to simulate the generation of thermal stresses due to hydration heat and restraint by using a thermal stress measuring device (TSD). The net effects of time-dependent properties of hardening concrete can be well incorporated in TSD due to simultaneous development of temperature and corresponding stress in restrained specimen. Moreover, experiments were conducted to measure a precise value of early-age autogenous shrinkage (AS) and to evaluate the basic creep model with respect to AS. In cracking risk analysis, precise value of early-age AS must accurately predict the time of shrinkage-induced cracking. A significant difference exists between apparent (including AS) and real basic creep (excluding AS) for low water-cement ratio concrete and early-age normal strength concrete. To improve the crack sensitivity analysis, it is recommended to precisely measure early-age AS and modify the basic creep model to prevent from possible errors and computational problems.
Keywords: autogenous shrinkage, early-age shrinkage, hydration heat, thermal stress measuring, basic creep, concrete cracking, simulation, crack sensitivity analysis, structural engineering