Liu, "Studies on foam stabilization mechanism of air-entraining agent
and improvement of freeze-thaw durability of concrete," Concrete, vol.
It is because the mixed air-entraining agent
in concrete can make them up effectively and thus improve the durability.
Moreover, according to the researchers (Kurdowski 2003), these bubbles are slightly bigger than those trapped under the influence of an air-entraining agent
, but their stability is lower.
One paper emphasizes the effects of void parameters on concrete FT resistance, and one paper introduces a new method for determining the air-entraining agent
demand of a concrete mixture.
In view of the benefit of air-entraining to freeze-thaw resistance of concrete [12-16], the content of the air-entraining agent
was also considered as a main factor in this paper.
[10-13] was recommended for nearly all concretes, principally to improve resistance to freeze-thaw cycles when exposed to water and deicing chemicals in cold regions.
The 42.5# Ordinary Portland cement (the compressive strength should reach 22.0 MPa and 42.5 MPa at days 3 and 28; the flexural strength should reach 4.0 MPa and 6.5 MPa at days 3 and 28), tap water, river sand (fineness modulus was 2.6), crushed natural stone aggregate (diameter ranges from 5 mm to 20 mm), and air-entrained admixture (rosin soap air-entraining agent
was used) were used in this experimental study.
That variability is especially owed to the effects on air voids of aggregate, cement and supplementary cementitious materials; air-entraining agent
dosage; batch contaminants; mixing dynamics; temperatures during batch-to-placing window; and, mix slump changes.
In this study, to explore high-durability concrete for the future construction of the roadside structures, air-entraining agent
and carboxylated styrene-butadiene latex were added for the modification of Portland cement concrete and the corresponding performance tests were conducted, including freeze-thaw tests, compressive strength tests, and chloride ion permeability tests.
The mix proportions of A-E-C in per cubic meter is are follows: cement (412.68 kg/[m.sup.3]), sand (586.83 kg/[m.sup.3]), coarse aggregate (1186.00 kg/[m.sup.3]), water (164.30 kg/[m.sup.3]), and air-entraining agent
The amount of the air-entraining agent
admixture required to obtain the target air percentage in a concrete mix increases with the increase in the fly ash content in the mix, say Chaitanya Paleti, graduate student, and Jan Olek, professor, School of Civil Engineering, Purdue University, and Tommy E.
Foam index tests show that the ash's adsorption of air-entraining agents
is extremely low--making the material particularly suitable for applications requiring freeze-thaw resistance.