| 摘要: |
| 为研究海水浸泡养护对磷酸钾镁水泥（MKPC）浆体微观结构和性能的影响，测试了不同养护条件下MKPC浆体试件的抗压强度和干燥收缩率，分析了其物相组成和微观结构.结果表明：在海水浸泡环境下,如果MKPC浆体试件已凝结且具有一定的初始结构强度，其主要水化产物MgKPO4·6H2O（MKP）在呈弱碱性的海水环境下溶解度低、水解现象减轻；海水的渗入使MKPC浆体试件的水化反应得以持续进行，水化反应生成较多的MKP，在弱碱性海水环境下，MKP更易结晶，生成的MKP晶体结晶程度高、缺陷少，后续生成的MKP晶体不断填充MKPC硬化体的孔隙，使硬化体结构趋于致密；自然养护3d后浸入海水养护的MKPC试件有较高的抗压强度和较低的干燥收缩率，其28，60d抗压强度较全程自然养护的MKPC试件分别提高13%和5%，而其60d干燥收缩率仅为全程自然养护MKPC试件的12%，为28d后浸入海水养护MKPC试件的23%. |
| 关键词: 磷酸钾镁水泥（MKPC） 海水养护 抗压强度 干燥收缩率 微观结构 |
| DOI：103969/j.issn.1007 9629201705003 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目（51578475）；住房和城乡建设部科研开发项目(2014 K4 031，2014 K4 024； 住建厅科技项目2014ZD97/101) |
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| Effect of Seawater Curing on Microstructure and Properties of Magnesium Potassium Phosphate Cement Paste |
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XU Xuanchen, YANG Jianming, GU Mingxuan, LI Xiaohua
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College of Civil Engineering, Yancheng Institute of Technology, Yancheng 224051, China
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| Abstract: |
| In order to study effect of early seawater curing on microstructure and properties of magnesium potassium phosphate cement(MKPC) paste, the compressive strength and drying shrinkage of MKPC paste specimens under different curing conditions, and the phase composition and microstructure were analyzed.The results show that there is an obviouse effect of early seawater curing on the properiets of MKPC paste. If MKPC paste is hardening and has a certain initial structural strength, the main hydrate MgKPO4·6H2O(MKP) the gradual infiltration of seawater makes the hydration reaction of MKPC paste sustained in sea， and more MgKPO4·6H2O crystals with high crystallization degree and less defect are formed and filled in pores in hardened MKPC paste, and that the structure of harden MKPC paste tends to be dense. For this reason, MKPC paste specimens, were immersed in sea water after 3d natural curing, have higher compressive strength and lower deformation, its 28d and 60d compressive strength are respectively 13% and 5% higher than that of MKPC paste in natural curing condition, and its 60d shrinkage deformation is 12% that of MKPC paste in natural curing condition and 23% than that of MKPC paste in seawater condition after 28d natural curing. |
| Key words: magnesium potassium phosphate cement(MKPC) seawater curing compressive strength drying shrinkage microstructure |
