混合骨料级配对不同浓度充填膏体流变性能影响试验研究

Experimental Study on the Effect of Mixed Aggregate Gradation on Rheological Properties of Filling Paste with Different Concentrations

为明确混合骨料配比及粒径级配对不同浓度充填膏体料浆流变性能的影响,以煤矸石和河砂为混合骨料,对不同骨料粒径特征分析,开展不同骨料配比、不同浓度条件下的流变试验,通过宾汉姆模型转换得到流变参数和流变特性曲线。试验结果表明:混合骨料配比和浓度共同影响料浆流动性,相对塑性黏度系数和相对屈服应力均随浓度增加而增大,相对塑性黏度系数随河砂比例增加而增加,相对屈服应力随河砂比例增加呈"N"形变化;混合骨料中河砂比例大于煤矸石时,相对塑性黏度系数增幅明显,相对剪切应力先减小后增大,适当增加细颗粒含量能降低料浆输送阻力,混合骨料级配对料浆流变性能有一定程度的影响。

In order to clarify the effects of mixed aggregate ratio and particle size gradation on the rheological properties of filling paste slurry with different concentrations,coal gangue and river sand were used as mixed aggregates to analyze the particle size characteristics of different aggregates.Rheological tests under different aggregate ratios and different concentrations were carried out,and rheological parameters and rheological characteristic curves were obtained through Bingham model conversion.The test results show that,the ratio and concentration of the mixed aggregate affect the slurry fluidity together.The relative plastic viscosity coefficient and the relative yield stress increase with the increase of the concentration,the relative plastic viscosity coefficient increases with the river sand content,and the relative yield stress changes with the increase of the river sand content as an"N"shape.When the river sand content in the mixed aggregate is greater than that of coal gangue,the relative plastic viscosity coefficient increases significantly,and the relative shear stress first decreases and then increases.Appropriately increasing the content of fine particles can reduce the transportation resistance of the slurry,and the mixed aggregate gradation has a certain degree of influence on the rheological properties of the slurry。