多元辅助胶凝材料改性水泥混凝土工作及力学性能研究

Study on Workability and Mechanical Properties of Blended Concrete Modified by Multi-component Auxiliary Cementitious Materials

为了促进工业副产品在水泥混凝土中的利用,采用辅助胶凝材料对水泥混凝土进行改性,并对其工作及力学性能进行研究。将粉煤灰(FA)、矿渣(GGBS)、偏高岭土(MK)和硅灰(SF)按重量代替普通硅酸盐水泥(OPC)的30%~50%,按预先确定的比例混合,测试其坍落度,表征混凝土施工和易性。同时,对四元混凝土在不同龄期的抗压强度和抗弯拉强度进行测试。试验结果表明,掺加粉煤灰(30%和50%)可提高混合料的和易性,GGBS、MK的加入也有助于坍落度的增加,但添加硅灰会降低混凝土的和易性。四元混凝土的抗压强度随辅助胶凝材料的加入而增加。在365天龄期,最佳混合料8和混合料11的抗弯强度比控制混合料高出25%和10%,多元辅助胶凝材料改性水泥混凝土具有显著的实用价值。

In order to promote the recycling of industrial by-products in cement concrete,auxiliary cementitious materials are used to modify cement concrete,and its work and mechanical properties are studied.Fly ash(FA),slag(GGBS),metakaolin(MK)and silica fume(SF)are replaced by weight by 30-50%of ordinary Portland cement(OPC),mixed in a predetermined ratio,and tested for Slump,characterizing concrete construction and workability.At the same time,the compressive strength and flexural tensile strength of quaternary concrete at different stages were tested.The test results show that the addition of fly ash(30%and 50%)can improve the workability of the mixture.The addition of GGBS and MK can also help increase the slump,but the addition of silica fume will reduce the workability of concrete.The compressive strength of quaternary concrete increases with the addition of auxiliary cementitious materials.At the age of 365 days,the flexural strength of the best mix 8 and mix 11 is 25%and 10%higher than that of the control mix.Multi-component auxiliary cement modified cement concrete has a significant practical value.