碱式硫酸镁水泥早期水化和力学性能的电阻抗法试验研究  

A study on the early hydration and mechanical properties of BMSC using the method of electrical impedance

作　　者：曾翔超 ZENG Xiangchao(Department of Civil Engineering,Yangtze Normal University,Chongqing 408100,China)

机构地区：[1]长江师范学院土木学院,重庆408100

出　　处：《哈尔滨工程大学学报》2024年第7期1415-1420,共6页Journal of Harbin Engineering University

基　　金：重庆市自然科学基金项目(CSTB2022NSCQ-MSX0426);国家自然科学基金项目(51678304,51662035);重庆教育委员会科学技术研究计划重点项目(KJZD-K202201406).

摘　　要：针对碱式硫酸镁水泥的早期水化行为和力学性能关系的研究尚不充分,本文主要采用电阻抗法结合抗压强度测试、X射线衍射、扫描电镜和压汞法进行了研究。根据实测电阻率曲线将碱式硫酸镁水泥早期水化过程分为诱导期、加速期和减速期3个阶段。利用获得的电阻率微分曲线上的特征点A(电阻率开始增长的时间)和特征点B(电阻率增长达到最大值的时间)求得BMSC的初凝和终凝时间。此外,建立碱式硫酸镁水泥水化24 h电阻率与28 d抗压强度的拟合直线方程,通过实测水化后24 h的电阻率能准确预测碱式硫酸镁水泥的28 d抗压强度,为BMSC水化早期性能监测提供一种可行、准确的方法。The relationship between the early hydration processes and mechanical performances of basic magnesium sulfate cement(BMSC)has not been comprehensively researched.In this paper,we investigate this relationship using electrical impedance spectroscopy combined with measurements of compressive strength,X-ray diffraction analysis,scanning electron microscopy,and mercury intrusion porosimetry.The early hydration process of BMSC can be clearly divided into three stages:induction,acceleration and deceleration according to the resistivity curve obtained from our measurements.Notably,the initial and final setting times of BMSC can be estimated by identifying two critical points on the differential resistivity curve:point A(where the resistivity growth rate starts rising)and point B(where the resistivity growth rate reaches its maximum)thanks to a good linear correlation between them.Furthermore,we have developed a fitted linear equation that correlates the 24 h resistivity of BMSC with its 28 d compressive strength.This model allows for the precise prediction of BMSC’s 28 d compressive strength based on resistivity measurements at 24 h,offering a feasible and accurate method for early monitoring of BMSC performance in terms of hydration.

关 键 词：电阻抗法 碱式硫酸镁水泥 力学性能 早期水化行为 线性拟合 抗压强度 特征点 

分 类 号：TU378.2[建筑科学—结构工程]