ASTM C78

This test method is used to determine the flexural strength of specimens prepared and cured in accordance with Test Methods C 42/C 42M or Practices C 31/C 31M or C 192/C 192M. Results are calculated and reported as the modulus of rupture. The strength determined will vary where there are differences in specimen size, preparation, moisture condition, curing, or where the beam has been molded or sawed to size.

The results of this test method may be used to determine compliance with specifications or as a basis for proportioning, mixing and placement operations. It is used in testing concrete for the construction of slabs and pavements.

1. Scope

1.1 This test method covers the determination of the flexural strength of concrete by the use of a simple beam with third-point loading.

1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

2. Referenced Documents

ASTM Standards
C1077 Practice for Laboratories Testing Concrete and Concrete Aggregates for Use in Construction and Criteria for Laboratory Evaluation
C192/C192M Practice for Making and Curing Concrete Test Specimens in the Laboratory
C31/C31M Practice for Making and Curing Concrete Test Specimens in the Field
C42/C42M Test Method for Obtaining and Testing Drilled Cores and Sawed Beams of Concrete
C617 Practice for Capping Cylindrical Concrete Specimens
E4 Practices for Force Verification of Testing Machines

Index Terms

beams; concrete; flexural strength testing; modulus of rupture; Concrete test specimens; Flexural testing--concrete; Three-point loading; ICS Number Code 91.100.30 (Concrete and concrete products)

Citing ASTM Standards

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