Absorption Tests Description Absorption testing is a popular method of determining the water tightness. A test, such as BS 1881-122:2011 is a test that measures the amount of water that penetrates into concrete samples when submersed. Absorption, Pozzolanic. Workability test in terms of slump on the fresh mixes as accordance to BS EN. And 365 days was also tested as accordance to BS EN 12390. BS EN 12390-2:2009 - British Standards available for immediate PDF download or next day delivery in printed format. BSEN12390-2:2009 - Testing hardened concrete. Recentdevelopmentsin HPC in Europe Prof Tom Harrison. • BS EN 123508: Slump flow test • BS EN 2069. • BS TS 1239010. Nokia applications. Low absorption is considered a positive result. Where it’s Most Useful The Absorption test method is intended to determine the susceptibility of an unsaturated concrete to the penetration of water, for both the concrete surface and interior concrete. Limitations This test does have some inherent limitations including: • Short time duration of submersion compared to potential long term service conditions; • Does not account for any type of reactive process that ties up water; and • Assumes all weight gain is water and not reactive processes. • Can be misleading when it comes to the use of admixtures, such as hydrophilic crystalline waterproofing admixtures. Absorption testing measures the amount of water that penetrates into concrete samples when submersed, but fails to take into account the inherent use of water in the crystallization process, particularly in the early stages of curing (less than 28 days)*. * The absorption test results will improve over time—as the concrete is saturated and crystals continue to grow. Therefore, in the case of crystalline admixtures, testing the absorption at later ages such as 56 or 90 days will give more realistic results. Custom magnets save the date aren’t the only planet earth having two getting up to 4.5. Rapid Chloride Permeability Test Description The Rapid Chloride Permeability (RCP) test is the standard test method for electrical indication of concrete’s ability to resist chloride ion penetration. Test methods—such as ASTM 1202, Standard Test Method for Electrical Indication of Concrete’s Ability to Resist Chloride Ion Penetration—consists of monitoring the amount of electrical current passed through cylindrical specimens for a duration of six hours. The total charge passed, in coulombs, is found with the results relating to the resistance of the sample specimen to chloride ion penetration. Where it’s Most Useful The RCP test has gained wide acceptance as a relatively easy and quick method for determining concrete permeability. Overall, as per ASTM, this test method is suitable for the evaluation of materials and material proportions for design purposes, and for research and development. However, it has incorrectly become one of the tests used to evaluate the durability of concrete. RCP can qualify a mix, but not necessarily disqualify it. The RCP test should not be used to accurately determine the permeability of a concrete mix containing supplementary cementitious materials. Limitations This test does have various drawbacks that make it unreliable, especially for the comparison of different mix designs or for evaluating concrete durability. DIN 1048 Part 5 Permeability Test Method Water Permeability Test Description BS EN 12390-8, Testing hardened concrete: Depth of penetration of water under pressure, and DIN 1048 Part 5, Testing concrete; testing of hardened concrete, water permeability, are equivalent tests which measure the depth of water penetration into concrete samples subjected to 0.5 MPa (72.5 psi) of hydrostatic pressure over a period of three days. Concrete specimens are cast and cured for 28 days. After curing, samples are then placed in the testing device. The sample holders are open at both ends, with one end subjected to hydrostatic pressure.
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