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Aggregates and Water

Aggregate Grading for Strong Concrete Mixes

Description

Aggregate grading describes the particle size distribution in a sample of aggregate. It is important for making a concrete mix that has enough strength, reasonable workability, and minimal segregation. The right grading also helps concrete stay economical.

There are four main types of aggregate g...

Transcript

集料级配表示集料样品中颗粒的粒径分布。

级配良好的集料含有形成致密基质所需的全部集料粒径分级,且各粒径比例适当,以使空隙率达到最小。

相应的级配曲线是一条连续平滑的曲线,表明颗粒尺寸范围较宽。

当大部分颗粒能够通过某一特定筛网,但被下一个更细的筛网截留时,表明这些颗粒主要具有相同的粒径。

这代表一种均匀或单一粒径级配的集料,在级配曲线上表现为一条近乎垂直的线。

如果粗细集料通过两个尺寸相差较大的筛子时,通过的集料比例大致相同,表明中间粒径范围的集料缺失,这种情况称为间断级配,并在级配曲线上表现为一段水平线。

当缺乏细集料时,该混合料称为开级配,导致粗颗粒之间存在较大的孔隙。相应的级配曲线在较小粒径范围内...