ASTM C1038
Full Name
ASTM C1038 – Standard Test Method for Expansion of Hydraulic Cement Mortar Bars Stored in Water
Scope
ASTM C1038 is a standard test method used to determine the expansion of mortar bars made with hydraulic cement when stored in water. This test is specifically designed for cements where sulfate is an integral part of the composition.
Key aspects of ASTM C1038:
- Purpose: the main purpose is to measure the amount of expansion a mortar bar undergoes when submerged in water. This expansion can be linked to the amount of sulfate present in the cement, as excessive sulfate content can lead to excessive expansion.
- Applicability: the test method is applicable to various hydraulic cements, including portland cement, blended cement, and masonry cement.
- Specimen preparation: mortar bars are prepared according to specific proportions of cement, sand, and water, and then cured under controlled conditions.
- Test procedure: the prepared mortar bars are immersed in water for a specified period (typically 14 days), and their length changes are measured using a length comparator.
- Significance: this test method helps assess the potential for sulfate attack, a chemical reaction that can cause expansion and cracking in concrete structures exposed to sulfate-rich environments. The results can be used to evaluate the suitability of cement for use in such environments and to control the sulfate content in cement production.
Limitations:
- The test method does not simulate all real-world exposure conditions, and the results may not perfectly predict long-term performance in the field.
- Other factors, such as temperature, humidity, and the presence of other aggressive chemicals, can also influence the expansion of concrete in sulfate environments.
ASTM C1038 Accredited Laboratory
Applied Testing & Geosciences, LLC is accredited for performing tests using the ASTM C1038 standard.
Contact us today to learn more about our testing capabilities and how we can support your business.
Resources
Keywords
mortar bars; expansion; hydraulic cement; sulfate; water storage; length comparator; length change; curing; autoclave expansion