Previously we discussed acceptance testing of concrete according to ASTM C31, Standard Practice for Making and Curing Concrete Test Specimens in the Field and ASTM C39, Standard Test Method for Compressive […]
For quality assurance in concrete construction, the most common acceptance criterion is the compressive strength of the concrete. A field technician makes specimens according to ASTM C31, Standard Practice for […]
At Beton we review project specifications for various reasons. Sometimes it’s to develop concrete mixture proportions that will help a contractor meet the requirements. Sometimes it’s to come up with […]
There are generally three aspects to the performance of a structure. The first is structural. The structure needs to resist the gravitational, wind, and other loads to which it will […]
ASTM C1778, “Standard Guide for Reducing the Risk of Deleterious Alkali-Aggregate Reaction in Concrete,” can help you decide how best to mitigate expansions due to reactive aggregates. It covers both […]
Despite our need for durability and high performance, the most common design criterion for concrete is compressive strength. Usually we specify the 28-day strength, that is, the compressive strength after […]
When finishing air-entrained concrete, less is more. Hard-troweled surfaces and air-entrained concrete don’t mix. If you need to entrain air—that is, if the concrete will experience cycles of freezing and […]
Throughout my career, our industry has been pursuing performance specifications for concrete. That is, we want specifications for what the concrete must do, not what it must be. The sticking […]
Although engineers usually think of compressive strength as the most important property of concrete, concrete for slabs on ground is different. According to ACI 302, for slabs on ground the […]
In Minnesota, Iowa, and South Dakota, we sometimes see aggregate popouts, particularly in concrete flatwork. Popouts are unsightly surface defects that may appear a few hours to a few weeks […]