Entrainment of a small quantity of air in cement concrete has been found to significantly enhance the durability of concrete. The suggested limits stated for the air content are between 3% and 6.5%. Smaller percentages may cause deterioration to happen more quickly and larger percentages may decrease the strength without any enhancement in the durability of concrete.
Additionally, when admixtures are used to increase workability of concrete, the air content should be checked to guarantee that the percentage of air stays between 1% and 2% for ideal performance of the concrete structure.
An Air Entrainment Meter, as specified in ASTM standards, is used to establish these percentages. It comprises a pressure-tight flanged cylindrical measuring bowl, equipped with a removable flanged and conical cover assembly with a seal in between.
The conical cover is provided with an air valve and a pet cock for bleeding off the water. A cylindrical stand pipe, which is graduated in percent of air content, is installed on the conical cover assembly.
The required pressure is applied to the specimen with the aid of a pressure bulb. The entire assembly is mounted on a flat base. Each apparatus package comes with a calibrating cylinder, funnel, pressure gage, trowel, and tamping bar.
Applicable Standards
Standard Features
- Calibration kit
- Rubber mallet
- Tamping rod
- Gaging trowel
- Measuring cylinder
- Straight edge
Optional Accessories
- Calibration kit
- Rubber mallet
- TO-345 Tamping rod
- TO-428 Gaging trowel
- Measuring cylinder
- Straight edge
- Syringe
MODEL TO-340-B
Air Entrainment Meter – Type B
The suitable control of entrained air in concrete is said to be one of the most crucial functions in present concrete manufacture. To the concrete engineer and technician, the Air Entrainment Meter provides an instrument for application in the testing and designing of concrete mixes. The instrument is built so that the operating parts form an integral unit. The container is sturdy, therefore providing an accurate device for the performance of unit weight testing. For ease of task, the tare weight in grams is stamped on the bottom. When used with the supplied monograph, the air meter delivers quick and easy particle density and percent of free moisture in aggregate determinations. The Air Entrainment Meter’s multi-range feature correctly measures entrained air up to 22%. The package includes syringe, straight edge, and carrying case.
Key Features
- Shock-proof pressure gage mounting
- Seven-liter capacity
- Heavy-duty plastic carrying case for easy transport to site
- Lightweight aluminum construction
Model TO-340-B Specifications
| . |
. |
| Dimensions |
248 x 337 mm |
| Capacity 7 |
liters |
| Readings |
Up to 22% entrained air |
| Accuracy |
+0.25% full scale |
| Aggregate size |
50 mm maximum |
| Container |
Tare weight stamped on bottom; two piece clamping device for positive seal |
| Pressure gage |
In shockproof mounting |
| Weight |
6.8 kg |
Applicable Standards
- EN 12350-7; ASTM C 231, ASTM C 213, AASHTO T-152
Standard Features
- Calibration kit
- Rubber mallet
- TO-345 Tamping rod
- TO-428 Gaging trowel
- Measuring cylinder
- Straight edge
Optional Accessories
- Calibration kit
- Rubber mallet
- TO-345 Tamping rod
- TO-428 Gaging trowel
- Measuring cylinder
- Straight edge
- Syringe
Air Entrainment Meter – Type A and B
Air Entrainment Meter – Type B - Picture 1
Air Entrainment Meter – Type B - Picture 2