碳化对含花岗岩石粉硫氧镁水泥的抗压强度和耐水性的影响
Effect of carbonation on the properties of granite-bearing oxysulfate oxide cement
靳凯戎 1张晓静 1毕万利 2王德志 3韩静云4
作者信息
- 1. 宁夏大学 土木与水利工程学院 银川 750021
- 2. 辽宁科技大学材料与冶金学院,辽宁鞍山 114051
- 3. 宁夏大学 土木与水利工程学院 银川 750021;宁夏大学旱区现代农业水资源高效利用教育部工程研究中心 银川 750021;宁夏大学宁夏土木工程防震减灾工程技术研究中心 银川 750021;宁夏大学宁夏节水灌溉与水资源调控工程技术研究中心,银川 750021
- 4. 北方民族大学土木工程学院,银川 750030
- 折叠
摘要
以CO2气氛作为养护条件,研究了不同掺量的花岗岩石粉(GP)对硫氧镁(MOS)水泥性能的影响,结合X射线衍射仪(XRD)、同步综合热分析仪(TG-DSC)、扫描电镜(SEM)和压汞仪(MIP)对MOS水泥水化产物及微观结构做了分析.结果表明,碳化28 d后的掺加40％GP的MOS水泥强度保留系数提高至1.12;碳化28 d后浸水120 d强度保留系数为0.94,较空白样提高了123.8％;MOS水泥碳化过程中基体内Mg(OH)2转化为MgCO3·zH2O晶体,有利于改善MOS水泥的力学性能;GP改善了MOS水泥孔结构,提高了密实度,降低了CO2吸收率,减弱了CO2的侵蚀作用;GP和碳酸镁相的共同作用提升了MOS水泥碳化后的力学性能和耐水性.
Abstract
The properties of magnesium oxysulfate (MOS) cement with different granite powder (GP) contents with CO2 curing were studied. The hydration products and microstructure of MOS cement were analyzed using X-ray diffraction (XRD),simultaneous comprehensive thermal analyzer (TG-DSC),scanning electron microscope (SEM) and mercury porosimeter (MIP). The results shows that the strength retention coefficient of MOS cement containing 40％ GP reached 1.12 with standard curing for 28 days followed by 28 days of CO2 curing;when MOS cement was CO2-cured for 28 days and then immersed in water for 120 days,the strength retention coefficient reached 0.94,which was 123.8％ higher than that of blank samples. MgCO3·zH2O crystals were generated after MOS cement underwent CO2 curing,which had a positive effect on the mechanical properties and water resistance by reducing matrix expansion caused by MgO hydrating to Mg(OH)2. GP increased the matrix density,reduced the CO2 capture rate,and decreased CO2 erosion of MOS cement by optimizing the pore structure. The presence of GP and magnesium carbonate phases improved the compressive strength of MOS cement after carbonation and immersion.
关键词
硫氧镁水泥/碳化/耐水性/碳酸镁Key words
magnesium oxysulfate cement/carbonation/water resistance/magnesium carbonate引用本文复制引用
基金项目
国家自然科学基金资助项目(51968060)
国家自然科学基金资助项目(52368037)
宁夏青年拔尖人才培养工程(2080116)
宁夏重点研发计划项目(2022BEE03001)
宁夏一流学科项目(NXYLXK2021A03)
宁夏自然科学基金(2023AAC03040)
出版年
2024
国家科技期刊平台
NSTL
万方数据