What defines the initial setting time of concrete in this test?

It is the elapsed time after the initial contact of cement and water required for the mortar to reach a penetration resistance of 3.5 MPa.

What defines the final setting time of concrete in this test?

It is the elapsed time after the initial contact of cement and water required for the mortar to reach a penetration resistance of 27.6 MPa.

Is the test performed on the full concrete mix?

No, the test is performed on mortar sieved from the fresh concrete sample using a 4.75-mm sieve to remove coarse aggregates.

What is the main apparatus used for IS 8142?

A penetration resistance apparatus, also known as a Proctor Penetrometer, equipped with a set of standard needles of varying cross-sectional areas.

IS 8142

: 1976

Method of test for determining the setting time of concrete by penetration resistance

CurrentSpecializedTesting MethodMaterials Science · Cement, Concrete, Aggregates and RCC

Download PDF BIS Portal Google

This standard details the method for determining the initial and final setting times of concrete by measuring penetration resistance. The test is performed on mortar sieved from a representative concrete sample, providing a more realistic assessment of in-situ setting behaviour compared to tests on cement paste alone.

Method of test for determining the setting time of concrete by penetration resistance

Quick Reference Values

Penetration Resistance for Initial Set3.5 MPa

Penetration Resistance for Final Set27.6 MPa

Sieve for Mortar Extraction4.75-mm IS Sieve

Standard Penetration Needle Areas645, 323, 161, 65, 32, and 16 mm²

Test Sample Temperature27 ± 2 °C

Key Formulas

Penetration Resistance (MPa) = P / A (where P is force in Newtons, A is needle area in mm²)

Practical Notes

This test is more representative of in-situ concrete setting than the Vicat apparatus test (IS 4031-5), which is performed on cement paste only.

It is particularly useful for assessing the performance of admixtures like retarders or accelerators and for planning mass concrete pours.

Maintaining the specified sample temperature is critical, as setting time is highly dependent on temperature.