WHAT IS PULLOUT TEST?
Determination of the pullout strength of hardened concrete by measuring the force required to pull an embedded metal insert and the attached concrete fragment from a concrete test specimen or structure. The insert is either cast into the fresh concrete or installed in hardened concrete is know as pull out test.
FACTORS AFFECTING THE CONCRETE PULLOUT TEST
The pull out strength can be related to compressive strength. Such strength relationships are depends (affected by) upon following factors:
- Level of strength development in that concrete.
- Bearing ring dimensions.
- The type of aggregates uses in concrete.
- Configuration of the embedded insert.
- Depth of embedment.
Prior to use, these relationships must be established for each system and each new combination of concreting materials. Such relationships tend to be less variable where:
- Pullout test specimens and compressive strength test specimens are of similar size.
- Pullout test specimens and compressive strength test specimens are compacted to similar density.
- Pullout test specimens and compressive strength test specimens are cured under similar conditions.
USES OF PULL OUT TEST
- Post-installed pullout tests may be used to estimate the strength of concrete in existing constructions.
- Determine in-situ compressive strength of the concrete.
- To determine the time to remove the forms and shores.
- Winter protection and curing may be terminated if strength of concrete has reached a specified level.