---
title: "ASTM C151"
url: "https://mat-cs.com/astm-c151/"
description: "This test method covers determination of the expansion of a hardened cement paste when exposed to the autoclave conditions in this method."
---

ASTM Standard

# ASTM C151

Standard Test Method for Autoclave Expansion of Hydraulic Cement

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## Significance and Use

4.1 The autoclave expansion test provides an index of potential delayed expansion caused by the hydration of CaO or MgO, or both, when present in hydraulic cement.3

## Scope

1.1 This test method covers determination of the expansion of a hardened cement paste when exposed to the autoclave conditions in this method.

1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.