骨架密实型矿料级配设计方法探究

Research on Gradation Design Method for Skeleton Dense Type Mineral Aggregate

矿料级配决定了矿料颗粒间嵌挤力的大小及混合料密实程度,对路面的抗剪强度影响很大。目前的级配设计方法没有在设计过程中考虑矿料的性状,只考虑了矿料粒径的大小,矿料性状对级配及混合料性能的影响只能通过完成配比后进行试验验证。针对骨架密实型级配设计方法,提出了将骨架密实级配混合料的骨架及密实分开进行设计的思路。"骨架"设计思路是由粗到细,逐级填充逐级找出最强"骨架",直至倒数第二档;密实设计思路是骨架级配设计完成的矿质级配集料的间隙率应等于最后一档料(最细的一档料)的体积,通过体积法完成密实填充。两种方法合并在一起,简称强度体积法(CBR-V法)。

The aggregate gradation determines the magnitude of the aggregate skeleton intergranular squeezing force and the dense of the mixture, which has a great influence on the shear strength of the pavement. The present gradation design method does not consider the properties of aggregate in the design process, but only considers the size of aggregate particles. The influence of aggregate properties on the gradation and mixture performance can only be verified by experiments after completing the proportion. Aiming at the design method of skeleton structure and dense structure gradation, in this paper, the idea of separating skeleton and dense of skeleton-dense gradation mixture has been put forward. The idea of 'skeleton' design is to find out the strongest skeleton structure step by step from coarse to fine and fill it step by step until the penultimate second grade. The idea of 'dense' design is that the voids in mineral aggregate VCADRC of mineral graded aggregate designed by skeleton gradation should be equal to the volume of the last stage(the smallest stage). The two methods are combined together, that is, the strength and volume design method, or CBR-V method.