不同岩性石粉关键物化指标及胶砂性能

Key physical and chemical indexes of different lithology stone powder and mortar performance

考虑石粉替代矿物掺合料在混凝土中的应用,选用6种不同岩性、3种不同细度的石粉研究其关键物化指标及胶砂性能。结果表明:同种石粉纯石粉亚甲蓝值是石粉与标准砂按1∶3比例的3~4倍,细度对亚甲蓝值影响不大,亚甲蓝值高胶砂流动性不一定差。石粉总碱含量、有效碱、可溶碱之间无相关关系,6种石粉有效碱含量占比计算为相同地区掺石粉混凝土碱含量计算提供了参考。玄武岩石粉较基准标稠用水量减少了2.2%,辉绿岩与基准持平,其余石粉较基准均有增加。6种岩性石粉缓凝效果均不明显,其中玄武岩石粉可缓凝10 min。6种岩性石粉胶砂流动度比均大于90%,其活性指数:凝灰岩石粉>石灰石粉>红砂岩石粉>玄武岩粉>辉绿岩>花岗岩。

Considering the application of stone powder instead of mineral admixture in concrete,six kinds of stone powder with different lithology and three different fineness were selected to study its key physical and chemical indexes and mortar performance.The results show that the methylene blue value of pure stone powder of the same kind of stone powder is 3 to 4 times that of stone powder and standard sand in a ratio of 1∶3.The fineness has little effect on the value of methylene blue,and the fluidity of high methylene blue value is not necessarily poor.There is no correlation between the total alkali content of stone powder,effective alkali and soluble alkali.The calculation of the effective alkali content of six kinds of stone powder provides a reference for the calculation of alkali content of concrete mixed with stone powder in the same area.The standard consistency water consumption of basalt rock powder has been reduced by 2.2%compared with the benchmark.Diabase remains the same as the benchmark,and the rest of the stone powder has increased compared with the benchmark.The retardation effect of the six kinds of lithological stone powder is not obvious,and the basalt rock powder can be retarded for 10 minutes.The fluidity ratio of the six kinds of lithological stone powder mortar is greater than 90%,and its activity index is:tuff powder>limestone powder>red sandstone powder>basalt powder>diabase>granite.