More stories about Testing

  • The Cost of Testing

  • Standardized Tests for SCC

    More of our customers are starting to ask us about the possibility of using self-consolidating concrete. What’s going on with the development of standardized tests for SCC?

  • Concrete Under Fire

    How thick should concrete be to withstand four hours of temperatures of 2000 degree F without degrading or failing? The concrete barrier likely will be exposed to more than 2000 degrees F. The barrier would be more than 30 feet tall and more than 30 feet long. It will be outdoors and subject to...

  • Testing Aggregates to Avoid Staining

    Is there a quick test to detect the presence of iron sulfide in aggregates? The aggregate I am considering will be used in an exposed decorative application, so repeated wetting and drying of the aggregate will occur at the surface. I also am concerned it may cause staining.

  • Compressive vs. Flexural Strength

    Is there a good way to correlate core compressive strength and flexural strength? I have a job in which there was only one beam broken, at 28 days, and there are not enough sets to perform any statistical analysis. We are planning to core the pavement and are looking for a comparison between the...

  • More on SCC

    Editor's note: Two readers responded to recent articles on self-consolidating concrete (SCC).

  • Relativity and Rheology

    Editor's note: Two readers responded to recent articles on self-consolidating concrete

  • Air Test Variability

    Is it common to get different air readings when using a pressure meter and a roll-a-meter or volumetric meter? I continually get a difference of about 0.8% to 1%, but I feel very sure my meters are calibrated correctly. The higher reading is from the pressure meter.

  • Is it the Slab's Fault?

    A flooring contractor has experienced problems on four occasions over the years with his two-part polyurethane floor covering not bonding to our concrete slab-on-grade. He has said that the acid-etch process prior to installing the covering did not react very well with our slab surface, based on...

  • Does Intermediate Rounding Decrease Accuracy?

    I have a further question regarding the rounding of compressive strength results (ôHow Precisely Should Labs Round off Compressive Strength Results?ö April, page 26).At our lab, we test 4x8-inch and 6x8-inch concrete cylinders for compressive strength, and we round to the nearest 10 psi according...