This standard is issued under the fixed designation C42/C42M; the number . of core test results.2 and that is free of is the individual responsible for analysis or. ASTM C42/C42M () Standard Test Method for Obtaining and Testing Drilled ASTM International, West Conshohocken. Free SCIRP Newsletters>> . ASTM C Potential Resistance to Degradation. In-situ Tests . Determine time from start until no free water is on ASTM C42, Coring, 3 cores/5, sf.
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SI units are shown in brackets. 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. When grinding fres capping of the bearing surfaces is.
In-place test methods may be used to estimate the level of strength development prior to attempting removal of concrete samples. The preferred length fre the capped specimen is between 1.
NOTE 3—Correction factors depend on various conditions such as moisture condition, strength level, and elastic modulus. Determine the average diameter by averaging two measurements taken at right angles to each other about the midheight of the specimen.
Significance and Use 3. When capping is employed the caps shall be as thin as practicable and shall be formed of high-strength gypsum plaster. Cores for Cree Strength 7.
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Average values are given in the table. Livro sobre Cimento Portland e Concreto. Therefore, results of two properly conducted fgee on asmt 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.
Measure the lengths of such cores in accordance with Test Method C If this is not practical, removal of concrete can proceed if the cut surfaces do not display erosion of the mortar and the exposed coarse aggregate particles are embedded firmly in the mortar.
CObtaining and Testing Drilled Cores and Sawed Beams of Concrete
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. The acceptance criteria for core strength is astn be established by the specifying authority.
The saw shall have a diamond or silicon-carbide cutting edge and shall be capable of cutting specimens which conform to the prescribed dimensions, without excessive heating or shock. 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. Core specimens with length-to-diameter ratios less than 1.
ASTM CC42M – 04 – Free Download PDF
NOTE 1—It is not possible to specify a minimum age when concrete is strong enough to withstand fred during removal, because the strength at any age depends on the curing history and strength grade of the concrete.
Ends are not to be capped. If necessary, saw the ends of the specimens until the following requirements are met: BoxFarmington Free, MI Additionally, this method may be used to provide strength information on older structures.
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. Cap free grind the cores, and test them within 48 h of receipt. 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.
Combining values of the two units may result in nonconformance. Parte 1 de 2 Designation: If time permits, the aztm should not be removed before it is 14 days old. The ends shall be sawed or ground to tolerance or capped in accordance with capping procedures for hardened concrete specimens of Practice C C 39 with the addition of the following information: The relationship is affected by many factors such as the strength level of the concrete, the in-place temperature and moisture history, and the strength gain characteristics of the concrete.
Length of Drilled Cores 6. A number in parentheses indicates the year of last reapproval. When preparing strength test specimens from samples of hardened concrete, samples that show defects or samples that have been damaged in the process of removal shall not be used.
ACI provides core strength acceptance criteria for new construction. For strengths above psi [70 MPa], test data on cores show that the correction factors may be larger than the values listed above. Measure core diameters qstm the nearest 0. Core diameters less than 3.
When the line of contact is not straight or contains projections or depressions having heights or depths greater than 0. They are applicable to both dry d42 wet concrete for strengths between and psi [14 to 42 MPa]. This standard has been approved for use by agencies of the Department of Defense. Originally published as C 42 — 21 T. Last previous edition C 42 —