Report on Methods for Estimating In-Place Concrete Strength

Abstract

ACI 228.1R - Report on Methods for Estimating In-Place Concrete Strength Standards Expert Document Status: Active Publication Date: January 2019 Document Language: English Publisher: ACI - American Concrete Institute Page Count: 52 DoD Adopted: No ANSI Approved: No IHS Segments: Abstract In-place tests are performed typically on concrete within a structure, in contrast to tests performed on molded specimens made from the concrete to be used in the structure.

Historically, they have been called nondestructive tests because some of the early tests, such as rebound number and ultrasonic pulse velocity, were noninvasive and did not damage the concrete.

Over the years, however, new methods have developed that result in superficial local damage.

Therefore the terminology “in-place tests” is used as a general name for these test methods, which includes those that do not damage the concrete and those that result in some near-surface damage.

In this report, the principal application of in-place tests is to estimate the compressive strength of the concrete.

The pull-off test can be used to estimate the tensile strength of concrete or evaluate bond strength between layers.

The significant characteristic of most of these tests is that they do not directly measure the compressive strength of the concrete in a structure.

Instead, they measure some other property that can be correlated to compressive strength (Popovics 1998).

The strength is then estimated from a previously established relationship between the measured property and concrete strength