The hydration kinetics of cement pastes with deoxyribonucleic acid (DNA)

The hydration kinetics of cement pastes with deoxyribonucleic acid (DNA) were studied. And the hydration products and microstructure of cement pastes were detected by XRD, SEM, and MIP. The results reveal that, compared with the blank sample, the maximum hydration heat flow and cumulative heat release rate of samples with DNA decrease. The compressive strength of the cement samples with DNA is reduced at ages of 3 d and 7 d. As the content of DNA increases, the strength of the test samples cured for 28 d shows a first increases and then decreases trend and the quantities of hydration products of Ca(OH) 2 decrease, but the types of hydration products have not changed. DNA converts more gel pores to capillary pores and macropores, and reduces the compactness of the cement pastes.