How long should a slump test take

Sorry, you do not have permission to ask a question, You must log in to ask a question. Join now! Do you need to remove the ads? Join Join TheConstructor to ask questions, answer questions, write articles, and connect with other people. Have an account? Log in Now. Join for free or log in to continue reading Remember Me! Prior to starting the test, the mold, base plate and all testing materials should be clean and free of any remnants of prior testing.

The inside surface of both the base and the mold should be dampened before beginning the test to reduce surface friction. Find a flat surface for testing and place the mold on top of the base plate.

This area should also be free from vibrations. The testing should only be performed on fresh, newly mixed concrete for best results. Fill the mold with fresh concrete in three layers see images Each layer should be tamped uniformly, 25 times using the rounded end steel rod.

Once the cone is full, level the top by removing any excess concrete from the top of the cone. The resulting unsupported concrete will therefore slump and the decrease in height should be measured to the nearest 5mm 0. True Slump — Here the general mass of the concrete drops evenly without any disintegration. This is the desired test result. Shear Slump — Here one side of the concrete shears or falls from the main portion of concrete.

This is an indication that the concrete lacks cohesion. Collapse Slump — Here the concrete completely collapses. This is an indication that the mix is too wet. The test is incredibly simple and is a great, quick method to check that multiple batches of the same concrete are consistent.

Freshly mixed concrete — that is soon to be poured — should meet a certain standard before being used as part of a construction project. A concrete slump test measures the consistency of a concrete batch to see how easily the concrete will flow. The test not only observes consistency between batches, but it also identifies defects in a mix, giving the operator a chance to amend the mix before it is poured on site.

The main reason to perform the test is to ensure batches of the same concrete are of constant quality and strength. The more water is added to a mix, the weaker the concrete gets. This test is just one of the ways we ensure the quality of our concrete. Water is the enemy when it comes to concrete strengths. This easy test is carried out in just seven stages, using a slump cone, a steel rod, and a measuring stick. Depending on the water-cement ratio of the mix, the concrete slump will fall under one of four categories:.

At Total Concrete , we can create a wide range of concrete mixes at our state — of — the — art batching plant , including ready mix concrete and specialty mixes.