What is ASTM C31?
Concrete cylinders being made in the field. …
How many times do you Rod a concrete cylinder?
Rod each layer 25 times throughout the layer depth distributing the roddings uniformly over the cross section. For subsequent layers, penetrate the previous layers about 1 inch. For 6 by 12 inch molds use a 5/8 inch diameter tamping rod and a 3/8 inch diameter rod for 4 by 8 inch molds.
When can you move concrete cylinders?
Cylinders must be transported back to the laboratory within 48 hours of casting. Some concrete mixtures may take longer to set and these specimens may be transported at a later time. In any event cylinders should not be moved or transported until at least 8 hours after final set.
How many concrete cylinder samples do you need to prepare?
A strength test result is always the average of at least two specimens tested at the same age. A set of 2 to 6 cylinders may be made from the same sample of concrete at a minimum for every 150 cubic yards (115 m3) of concrete placed.
What is ASTM C150?
The ASTM Standard Specification for Portland Cement (ASTM C150) provides for five types as follows: Sometimes called moderate-heat cement, it is intermediate between Type I and the low-heat Type IV cement.
What C31 test is under the standard ASTM test?
1. What C31 test under the Standard ASTM test method? Explanation: According to Standard ASTM test methods to evaluate field-placed concrete C31 test is for Test Method for Making and Curing Concrete Test Specimens in the Field. 2.
What c31 test is under the standard STM test?
Explanation: According to Standard ASTM test methods to evaluate field-placed concrete C231 test is for Air Content of Freshly Mixed Concrete by the Pressure Method.
How are concrete cylinders consolidated with a tamping rod?
For concrete to be consolidated with the tamping rod, place concrete in 3 equal layers for 6 ´ 12-inch cylinders; and in 2 equal layers for 4 ´ 8-inch cylinders For concrete to be consolidated by vibration, fill the mold in two equal layers. Place the concrete in the mold by distributing it around the inside of the mold with the scoop.
What kind of mold do you need for concrete cylinder?
Molds for casting cylinder specimens. Plastic molds are most common. Tamping rod with hemispherical tip – 5/8-inch (15-mm) diameter for 6 ´ 12-inch cylinders or 3/8-inch (10-mm) diameter for 4´ 8-inch cylinders, or a vibrator Rubber or rawhide mallet, 1.25 ± 0.50 lb. (0.6 ± 0.2 kg)
When do I need to use ASTM C31?
ASTM C31 – Making and Curing Concrete Test Specimens in the Field. When strength is used as a basis for acceptance of concrete, specimens must be molded and cured according to ASTM C31.
What do you need to know about concrete cylinders?
When making cylinders for acceptance of concrete, the field technician must test other properties of the fresh concrete to include temperature, slump, density (unit weight) and air content. This information should accompany the set of cylinders made for a particular pour or pour location.