JIS A 1128:2019 PDF Download

JIS A 1128:2019 is a standard that provides the method for determining the air content of fresh concrete using the reduction of pressure in an air chamber. It is specifically applicable for concrete made with ordinary aggregates that have a maximum size of 40 mm or smaller. However, this method is not suitable for concrete made with porous aggregates like artificial lightweight aggregates, as the aggregate correction factor in these cases cannot be accurately determined.

The standard also includes an informative annex (Annex A) that describes the water-column method for determining air content. It is worth noting that the test method specified in this standard is based on Boyle’s law, which states that the pressure and volume of a gas are inversely proportional when temperature is constant. This principle is applied to measure the air content of fresh concrete.

In addition, the standard provides notes to clarify certain aspects. Note 2 mentions that the air chamber method can be carried out with or without water injection. Note 3 indicates the corresponding International Standard and the symbol of degree of correspondence, which is ISO 1920-2:2016 Testing of concrete — Part 2: Properties of fresh concrete (MOD).