轻骨料-水泥石界面区微观结构特征

采用扫描电镜、X射线能谱分析、显微硬度等多种测试方法,测定了不同预饱水程度轻骨料一水泥石界面区水化产物的钙硅比、水泥石显微硬度以及孔结构等微观性能参数,研究了轻骨科预饱水程度对混凝土界面区结构与特征参数的影响,并与普通骨料混凝土进行了对比分析.结果表明,随着轻骨料预饱水程度的提高,界面区厚度从30μm增大至60 μm左右,距界面20μm范围内其显微硬度降低,而大于20μm处则相反,孔结构呈细化趋势,界面区得到增强,明显优于普通混凝土.

Microstructure Characteristics of Interfacial Transition Zone(ITZ) between Lightweight Aggregate and Cement Paste

The microstructure characteristics of the interfacial transition zone(ITZ) between Portland ce-ment paste and lightweight aggregate with different pre-wetting degree were investigated,and comparison was made to the crushed stone concrete.Scanning electron microscope(SEM),energy dispersive X-ray a-nalysis system(EDXA),microhardness test and pore structure test were used to analyze the ITZ thick-ness,element distribution,calcium oxide/silica ratio,microhardness and pore structure.The results show that the ITZ thickness around lightweight aggregate particles will increase from 30 μm to 60 μm,the mi-crohardness reduce within 20 μm while it will increase beyond 20 μm.It is found that the pore structure is refined and the ITZ will be improved with the pre-wetting degree increasing,better especially than the crushed stone concrete.