Influence of Drying on the Microstructure of Hardened Cement Paste: A Mercury Intrusion Porosimetry, Nitrogen Sorption and SAXS Study

Abstract

In view of the life-cycle assessment of concrete pavement, three-dimensional behavioral simulation was conducted by integrating constitutive laws for cracked/uncracked reinforced concrete, modeling of pore water inside cracks and multi-yield surface plasticity for soil to investigate the fatigue life under high-cycle moving loads. Presented is a discussion that the balanced pavement requires thicker slabs than those required by current design codes on medium compacted soil foundations, but for too much looser foundation, it is over-designed, conversely. Then, a new design approach is proposed in terms of the slab thickness by considering nonlinear coupling with soil foundation. When the stagnant water exists on the slab with cracks, the numerical analysis shows the excessive pore water pressure in cracks at the upper layers of the concrete pavement. The engineering experience is proved such that the deterioration of concrete slabs is accelerated by water and the fatigue life is dramatically shortened compared to the dry situation.