What does air void mean?

Air voids are small airspaces or pockets of air that occur between the coated aggregate particles in the final compacted mix.

How do you calculate air void content?

Percent air voids is calculated by comparing a test specimen’s bulk specific gravity (Gmb) with its theoretical maximum specific gravity (Gmm) and assuming the difference is due to air. Once Gmm is known, portable non-destructive devices can be used to measure HMA density in-place.

What is the meaning of air void in construction?

The air void between aggregates is the air void between the skeletons formed by coarse aggregates, including the asphalt binder, fine aggregates, and air voids. The air void pays a role in determining the aggregate interlocking to some extent, and it also can reflect the aggregate compaction.

What is the air content in percentage?

The air in Earth’s atmosphere is made up of approximately 78 percent nitrogen and 21 percent oxygen. Air also has small amounts of other gases, too, such as carbon dioxide, neon, and hydrogen.

What is the percentage air?

What is the formula for air content?

Air Content (ac) It is define as the ratio volume of air (Va) to volume of voids (Vv) present in given soil mass. It is represent as ‘ac’ . ac = (Va / Vv)*100. Air Content (ac) is the Unit less.

How do you calculate VMA and VFA?

VFA = (VMA-Va)/VMA x 100 ▪ VMA = 100 – (Gmb x Ps)/Gsb ▪ Va = (Gmm-Gmb)/Gmm x 100 ▪ Pba = 100 x ((Gse-Gsb)/(Gsb x Gse)) x Gb ▪ Gse = (100-Pb)/((100/Gmm)-(Pb/Gb)) ▪ Pbe = Pb-(Pba/100) x Ps Page 24 ▪ What goes into determining the volumetric properties of a mix?

What do you mean by air content?

[′er ′kän‚tent] (materials) The volume of air voids in cement paste, mortar,or concrete, exclusive of pore space in aggregate particles; usually expressed as a percentage of total volume of the mixture.

How is VMA calculated?

CALCULATION VMA = Voids in mineral aggregate, in percent of bulk volume, Gsb = Bulk specific gravity of the aggregate, Gmb = Bulk specific gravity of compacted mix, Ps = Aggregate, percent by total weight of mix. Where: P1 = Percent by weight of aggregate 1, etc., G1 = Bulk specific gravity of aggregate 1, etc.

What is the percentage of air in concrete?

between four and seven percent
The amount of entrained air is usually between four and seven percent of the volume of the concrete, but may be varied as required by special conditions.