ASTM C Related for sampling of fresh concrete on which tests are to be performed to determine compliance with specific test methods in ASTM standards . Materials. Sampling. Testing. C Cement. C Agg. C Air. C Admix. C Ash. C Water. C Sampling Fresh Concrete. ACI C Sampling Freshly Mixed Concrete – Free download as PDF File 1 This practice is under the jurisdiction of ASTM Committee C09 on Concrete.
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The asfm requirements as to materials, mixtures, air content, temperature, number of specimens, slump, interpretation of results, and precision and bias are in specific test methods.
The air c1772 of the wet-sieved fraction of concrete is greater than that of the total concrete because the larger size aggregate which is removed does not contain air. Obtain samples from at least five different portions of the pile and combine them into one composite sample for axtm purposes.
Warning—Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure. Generally, a horizontal back and forth motion is preferred.
NOTE 2—Sampling should normally be performed as the concrete is delivered from the mixer to the conveying vehicle used to transport the concrete to the forms; however, specifications may require other points of sampling, such as the discharge of a concrete pump.
Smaller samples are not prohibited for routine air content, temperature, and slump tests. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of aetm limitations prior to use. The effect of these differences may need to be considered or determined by supplementary testing for quality control or test result evaluation purposes.
The containers shall be of a size sufficient to provide a composite sample size that is in agreement with the maximum aggregate size. Composite samples are required by this practice, unless specifically excepted by procedures governing the tests to be performed such as tests to determine uniformity of consistency and mixer efficiency.
Individual reprints single or multiple copies of this standard may be obtained by contacting ASTM at the above address or at phonefaxor service astm. No further reproductions authorized.
Procedures used to select the specific test batches are not described in this practice, but it is recommended that random sampling be used to determine overall specification compliance. A superscript epsilon indicates an editorial change since the last revision or reapproval. They shall be combined and remixed with atm shovel the minimum amount necessary to ensure uniformity and compliance with the maximum time limits specified in 4.
To preclude contamination or absorption by the subgrade, sample the concrete by placing three shallow containers on the subgrade and discharging the concrete across the container. Take the portions so obtained within the time limit specified in Section 4, and combine them into one composite sample for test purposes. Regulate the rate of discharge of the batch by x172 rate of revolution of the drum and not by the size of the gate opening.
Committee C09 has identified the location of selected changes to this practice since the last issue, C—14, that may impact the use of this practice. These requirements 1c72 to both tilting and nontilting mixers. NOTE 5—The waiting period prior to commencing the testing is needed because the mix water is input only seconds before discharge from the continuous mixer.
C39M – 16 – Compressive Strength of Cylindrical Parte 1 de 2 Designation: If you feel that your comments have not received a fair hearing you should make your views known to the ASTM Committee on Standards, at the address shown below.
Active Risk Management
Start astj specimens for strength tests within 15 min after fabricating the composite sample. Perform sampling by passing a receptacle completely through the discharge stream, or by completely diverting the discharge into a sample container.
Users of this standard are expressly advised that determination of the validity of any such patent rights, and atsm risk of infringement of such rights, are entirely their own responsibility. The concrete which passes the sieve shall fall into a batch pan of suitable size which has been dampened before use or onto a clean, moist, nonabsorbent surface.
CM – 12 – Microscopical Determination of Obtain these portions within the time limit specified in Section 4. Sample the concrete at the frequency specified by collecting two or more portions taken at regularly spaced intervals during discharge of the concrete. Approved October 1, Place only enough concrete on the sieve at any one time so that after sieving, the thickness of the layer of retained aggregate is not more than one particle thick.
NOTE 4—In some instances, the containers may have to be supported above the subgrade to prevent displacement during discharge.
ASTM C | Testing Services | Standard Practice for Sampling Freshly Mixed Concrete
Do not obtain portions of the composite sample from the very first or last part of the batch discharge Note 3. Shake or vibrate the sieve by hand or mechanical means until no undersize material remains on the sieve. Combining values from the two systems may result in non-conformance with the standard.
Your comments will receive careful consideration at a meeting of the responsible technical committee, which you may attend. Combine the samples so obtained into one composite sample for test purposes. ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard.
ASTM C Standard
The apparent strength of wet-sieved concrete in smaller specimens is usually greater than that of the total concrete in larger appropriate size specimens.
Take the samples so obtained within the time limit specified in Section 4 and combine them into one composite sample for test purposes. Scrape any mortar adhering to the sides of the wet-sieving equipment into the batch.
Combine into one composite sample for testing purposes. Warning —Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure.
Historical Version s – view previous versions of standard.