Click here to sign up. Download Free PDF. Firmanov Yl. A short summary of this paper. A number in parentheses indicates the year of last reapproval. A superscript epsilon e indicates an editorial change since the last revision or reapproval. This standard has been approved for use by agencies of the Department of Defense. SI units are shown in Concrete in Constructions brackets. Combining values from the two systems crete Cylinders may result in non-conformance with the standard.
These notes and footnotes 3. Significance and Use excluding those in tables and figures shall not be considered as requirements of the standard. It is the responsibility splitting tensile, and flexural strength of in-place concrete. Another use of this method is to provide strength 2. Referenced Documents information on older structures. There is no standard procedure Concrete and Concrete Aggregates and is the direct responsibility of Subcommittee to condition a specimen that will ensure that, at the time of test, C Current edition approved July 1, Published July Originally approved in International, Vol.
The moisture conditioning procedures in this test horizontal plane of the concrete as placed. A specimen drilled method are intended to provide reproducible moisture condi- perpendicular to a vertical surface, or perpendicular to a tions that minimize within-laboratory and between-laboratory surface with a batter, shall be taken from near the middle of a variations and to reduce the effects of moisture introduced unit of deposit when possible. NOTE 2—Prior to capping, the density of a core may be determined by weighing it and dividing it by the volume calculated from the average diameter and length, or by any other standard method for determining density.
Measure core diameters to the nearest asstm. C 39 with the addition of the following information: SI units are shown in brackets.
Determine the average diameter by averaging two measurements taken at right angles to each other about the midheight of the specimen. Measure the lengths of such cores in accordance with Test Method C If necessary, saw the ends of the specimens until the following requirements are met: Thus, these factors should be applied to high-strength concrete with caution.
Current edition approved Feb. A superscript epsilon e indicates an editorial change since the last revision or reapproval. Do not use specimens with projections or depressions greater than 0.
The values stated may not be exact equivalents, therefore each system must be used independently of the other. If the ratio of the length to the diameter of the core specimen exceeds 2. Therefore, results of two properly conducted tests on cores sampled from the same hardened concrete where a single test is defined as the average of two observations coreseach made on separate adjacent drilled 4 in. NOTE 3—Correction factors depend on various conditions such as moisture condition, strength level, and elastic modulus.
Additionally, this method may be used to provide strength information on older structures. They are applicable to both dry and wet concrete for strengths between and psi [14 to 42 MPa]. Thus, these factors should be applied to high-strength concrete with caution. Therefore, results of two properly conducted tests on cores sampled from the same hardened concrete where a single test asstm defined as the average of two observations coreseach made on separate adjacent drilled 4 in.
NOTE 2—Prior to capping, the density of a core may be determined by weighing it and dividing it by the volume calculated from the average diameter and length, or by any other standard method for determining density. Sampling and sample preparation requirements are given to ensure that dimensional requirements are met and that the specimens are comprised of intact sound concrete as free of flaws as the particular structure will allow. A specimen taken perpendicular to a vertical surface, or perpendicular to a surface with a batter, shall be taken from near the middle of a unit of deposit when possible and not near formed joints or obvious edges of a unit of deposit.
In-place test methods may be used to estimate the level of strength development prior to attempting removal of concrete samples. When capping is employed the caps shall be as thin as practicable and shall be formed of high-strength gypsum plaster. For strengths above psi [70 MPa], test data on cores show that the correction factors may be larger than the values listed above. Significance and Use 3.
Additionally, this method may be used to provide strength information on older structures. The ends shall be sawed or ground to tolerance or capped in accordance with capping procedures for hardened concrete specimens of Practice C A number in parentheses indicates the year c2 last reapproval. In-situ Tests.
The acceptance criteria for core strength is to be established by the specifying authority. ACI provides core strength acceptance criteria for new construction. Originally published as C 42 — 21 T. The preferred length of the capped specimen is between 1. Ends are not to be capped. If time permits, the concrete should not be removed before aetm is 14 days old. When capping is employed the caps shall be as thin as practicable and shall be formed of high-strength gypsum plaster.
Thus, these factors should be applied to high-strength concrete with caution. The saw shall have a diamond fdee silicon-carbide xstm edge and shall be capable of cutting specimens which conform to the prescribed dimensions, without excessive heating or shock.
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