因此，级配优化研究工作势在必行。
Therefore, the study of optimizing mix design must be enforced.
本工程为换填级配碎石。
该方法简单有效，可以达到子像素级配准精度。
The proposed approach is simple and effective, it can achieve an accuracy up to sub-pixels.
采用设计级配，将具有很好的经济效益和社会效益。
Using design gradating will bring the great social and economic benefit forth.
研究成果对于级配碎石推广应用研究具有促进作用。
The study is stimulative for the promotion and development of graded broken stone.
通过对级配进行比较分析，提出结构层关键筛孔施工控制指标。
Compare gradation of deferent position, then take construction guideposts of structure level.
通过对级配进行比较分析，提出结构层关键筛孔施工控制指标。
Compare gradation of deferent position, then take construction guideposts of structure level.
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