Experimental research on elastic modulus of high-performance concrete in bridges

Based on Shanxi local raw materials, the highway project from Jixian to Hejin and the investigation for C50 HPC of the superstructure in bridges, we research the law of elastic modulus of HPC under different curing conditions with an increase in age. We establish hyperbolic function model, logarithmic function model, and exponential function model to fit the elastic modulus of HPC and the age. According to the comparative analysis, the elastic modulus of HPC at early age can reach more than 80% in 28 days; the responding value of HPC under the same curing condition is lower than the values under the standard curing condition at the same age. The hyperbolic function is recommended to characterize the elastic modulus of HPC under standard condition and the logarithmic function is recommended under the same curing condition. By using the X-ray CT image analysis technique, it is concluded that the internal porosity rate is more less, concrete structure is more compact, and elastic modulus is greater as the growth of the age.