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We should check the self compacted concrete during placed on site by those tests:
1- For Filling Ability
a- Slump Flow
b- T50 cm slump flow.
c- V-funnel
d- Orimet
2- For passing ability : J ring
3- For segregation resistance:
a- GTM test
b- V funnel at T5 minutes.
slump test is the available test for self compacted concrete in site
Air content, concrete slump, temperature of concrete, air temperature and humidity (to determine the degree in which fresh concrete will be subjected to drying)
Slump, air content, unit weight and compressive strength tests are the most common tests for fresh concrete.
Slump is a measure of consistency, or relative ability of the concrete to flow. If the concrete can’t flow because the consistency or slump is too low, there are potential problems with proper consolidation. If the concrete won’t stop flowing because the slump is too high, there are potential problems with mortar loss through the formwork, excessive formwork pressures, finishing delays and segregation. Air content measures the total air content in a sample of fresh concrete, but does not indicate what the final in-place air content will be, because a certain amount of air is lost in transportation, consolidating, placement and finishing. Three field tests are widely specified: the pressure meter and volumetric method are ASTM standards and the Chace Indicator is an AASHTO procedure. Unit weight measures the weight of a known volume of fresh concrete. Pouring cylinders of fresh concrete and measuring the force needed to break the concrete cylinders at proscribed intervals as they harden, test compressive strength. According to Building Code Requirements for Reinforced Concrete (ACI318), as long as no single test is more than500psi below the design strength and the averages of three consecutive tests equals or exceeds the design strength, then the concrete is acceptable. If the strength tests don’t meet these criteria, steps must be taken to raise the average.
AT WORKING SITE SLUMP TEST AND IN ALONG WITH JOB TAKE SOME QTY OF CONCRETE AND PREPARE CUBE TO SEND FOR CUBE TEST AT CUBE TESTING LAB FOR FINAL FITNESS REPORT OF CONCRETE MATERIAL.
