DOI: 10.15986-j.1006-7930.2019.06.005
为室内研究卸料角度和粒径分布对级配碎石粗集料均匀性的影响,在优化砂盒法的基础上引入了均匀系数,可对多粒径颗粒混合料的均匀程度进行定量评价.对不同粒径的集料进行染色处理,获得若干截面上不同粒径颗粒的分布位置后,对其中粗集料均匀性进行了分析计算,经过多次重复试验获得最优卸料角度和粒径分布.结果表明:卸料角为45度左右时混合料中粗集料分布均匀性最优,减小混合料的粒度分布宽度和细集料含量能够提高混合料中粗集料分布的均匀性.本研究充分模拟了混合料的卸料过程,提供了一种新型的分析方法和评价指标,有效的减少了混合料在卸料过程中的离析.
For the research of effect of unloading angles and particle size distributional width on the uniformity of coarse aggregate of graded gravel, we used uniform coefficient which is based on the optimization of the sand box method to evaluate the uniform degree of the multi-size particle mixture quantitatively. After we dyed the different sizes of aggregate respectively, we obtained the distribution positions of different size granule at several cross-sections. After that we evaluated the uniformity of coarse aggregate by the analysis and calculation of uniformity. Finally we obtained the optimal discharge angle and particle size distribution through repeated tests.The results show that the distribution uniformity of coarse aggregate is optimal when the discharge angle is about 45, which can improve distribution uniformity of coarse aggregate in mixture through reducing particle size distributional width of mixture and fine aggregate content. This study fully simulates the unloading process of the mixture, and provides a new analytical method and evaluation index, which effectively reduces the segregation of the mixture during the unloading process.
