纳米CaCO_3对砂浆强度和微观结构的影响  

Effects of nano-CaCO_3 on cement mortar and micro structure

作　　者：管吕军 李若东[1] 杜喜龙 

机构地区：[1]青海大学水利电力学院,青海西宁810016

出　　处：《青海大学学报（自然科学版）》2016年第1期44-50,共7页Journal of Qinghai University(Natural Science)

摘　　要：为了解不同纳米CaCO_3粉末掺量对水泥砂浆力学性能和微观结构形貌的影响和发展规律,试验取纳米CaCO_3的掺量分别为0,0.4%,1.2%,1.8%,2.2%,3.0%,对不同掺量下砂浆的力学性能和微观结构进行比较分析。结果表明:纳米CaCO_3可明显提高砂浆的抗折强度和抗压强度,掺量为2.2%时,3,7,28 d龄期的砂浆抗折强度比基准提高了17.1%,18.4%,43.6%,抗压强度比基准提高了32.3%,26.8%,28.9%;同时该掺量下7 d的水泥砂浆,其微观结构的水化硅酸钙凝胶最多,孔隙率和裂隙最低,Ca(OH)_2的取向程度最低,结构最为致密。To understand the mechanical properties,micro-structure and morphology of cement mortar that mixed with the nano-CaCO3 powder,we took nano-meter CaCO3 dosage 0%,0.4%,1.2%,1.8%,2.2% and 3.0% to implement the test.The results show that the nano-CaCO3 can significantly improve the flexural strength and compressive strength of mortar.Compared with that of base,the flexural strength increased by 17.1%,18.4%,43.6% and compressive strength increased by 32.3%,26.8%,28.9% for the dosage of 2.2% after 3d,7d and 28 d,respectively.When the cement mortar with 2.2% nano-CaCO3 is 7 days,the number of C-S-H gel reaches its maximum in the micro-structure of the cement mortar,and the porosity of the cement mortar reaches the minimum.The orientation of the Ca（OH）2of the cement mortar reaches the lowest degree and the compactness of the structure of the cement mortar achieves the highest degree.

关 键 词：砂浆 纳米CACO3 抗折强度 抗压强度 微观结构 

分 类 号：TV41[水利工程—水工结构工程]