水泥浆体中可蒸发水的1H核磁共振弛豫特征及状态演变

1H-NMR RELAXATION AND STATE EVOLVEMENT OF EVAPORABLE WATER IN CEMENT PASTES

利用低场质子核磁共振方法研究了硬化水泥浆体中可蒸发水的横向弛豫特征及其状态演变。结果表明:随着龄期的增长,可蒸发水的弛豫时间分布逐渐趋向于短弛豫时间,主峰平均弛豫时间降低,凝胶水相对含量不断增大,毛细水含量降低。由于浆体内部水化产物的填充使得孔结构细化,可蒸发水集中在小孔隙中,并主要以凝胶水的形式存在。

Transverse relaxation time t2 and state evolvement of evaporable water in hardened cement pastes were investigated by means of low field 1H-nuclear magnetic resonance.The results show that as the curing time increases,the t2 distribution peaks shift gradually to the short t2 values combined with the weighted mean t2 of predominance peaks decrease.In addition,the relative content of gel water increases in correlation with the decrease of capillary water.As the results of hydration production filled the space between particles in the hardened cement pastes,the evaporable water became concentrated in the micropores and existed mostly as gel water.