Other stories by Kevin MacDonald

  • Preventing Dust on Concrete

    Dusting of slabs has several causes but always results when a layer of weak paste sits at concrete’s surface.

  • ASTM Standards

    Why are ASTM standards important and why should concrete producers pay attention and follow them?

  • Aggregate Gradation Matters

    How we buy and sell aggregate is quite different, and it can lead to trouble. Most specifications require coarse and fine aggregate to conform to the requirements, including the gradation, of ASTM C33.

  • Low Concrete Compressive Strength and Cores

    ACI 301 gives direction to what is to be done in the event compressive strength results have fallen below the specified strength.

  • Mix Designs and Polished Concrete

    Concrete that will be ground and polished benefits from having a larger coarse aggregate content than conventional structural concrete.

  • Specification for Ready-mix Concrete

    The purchaser is required to inform the ready-mix producer of the specification of the concrete mix. This should be a normal part of doing business.

  • Understanding Limestone in Cement

    My cement supplier is adding limestone to their cement. Is there anything to worry about and will I have to reduce the fly ash content?

  • Dealing with Cement Shortages

    Lots of things can disrupt the supply of cement but there are some things a ready-mix producer can do to mitigate the problem.

  • Onsite Additions for Concrete

    Take several precautions before making any concrete, starting with a trial batch under site conditions.

  • The Risks of Low-Cement Concrete

    What precautions should a producer take when making concrete with a ternary blend and only 25% cement?