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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CM – 12 – Microscopical Determination of These requirements apply 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 c1722 the continuous mixer. Expeditiously obtain and use the sample and protect the sample from the sun, wind, and other sources of rapid evaporation, and aetm contamination.
Start molding specimens for strength tests within 15 min after fabricating the composite sample.
ASTM C172 – Sampling Fresh Concrete
Avoid contamination with subgrade material or prolonged contact with and absorptive subgrade. Generally, a horizontal back and forth motion is preferred.
Composite samples are required by this practice, unless specifically excepted by procedures governing the aatm 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.
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. After removing the larger aggregate particles by wet-sieving remix the batch with a shovel the minimum amount necessary to ensure uniformity and proceed testing immediately. NOTE 4—In some instances, the containers may have to be supported above the subgrade to prevent displacement during discharge. For example, wet-sieving concrete causes the loss of a small amount of air due to additional handling.
The size of the samples zstm be dictated by the maximum aggregate size. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. This removal of larger aggregate particles is preferably accomplished by wet-sieving. A superscript epsilon indicates an editorial change since the last revision or reapproval.
Current edition approved Oct. Sample by repeatedly passing a c1772 through the entire discharge stream or by completely diverting the discharge into a sample container.
Mixers—Sample the concrete by collecting two or more portions taken at regularly spaced intervals during discharge of the middle portion of the batch. Sample the concrete at the frequency specified by collecting two or more portions taken at regularly spaced intervals during discharge of the concrete. Asm shall be combined and remixed with a shovel the minimum amount necessary to ensure uniformity and compliance with the maximum time limits specified in 4.
Warning —Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure.
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.
The apparent strength of wet-sieved concrete in smaller specimens is usually greater than that of the total concrete in larger appropriate size specimens. 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. Do not obtain portions of the composite sample from the very first or last part of the batch discharge Note 3.
After obtaining the composite sample, wait a minimum of 2 minutes and a maximum of 5 minutes before beginning tests Note 5. 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. Procedures used to select the specific test batches are not described in this practice, but xstm is recommended c12 random sampling be used to determine overall specification compliance.
ASTM C172.C172M – 14 – Sampling Freshly Mixed Concrete
The air content 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. This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years and if not revised, either reapproved or withdrawn.
Obtain these portions within the time limit specified in Section 4. No further reproductions authorized. The detailed requirements as to materials, mixtures, air content, temperature, number of specimens, slump, interpretation of results, and precision and bias are in specific test methods.
ASTM C / CM – 17 Standard Practice for Sampling Freshly Mixed Concrete
NOTE 2—Sampling should normally be performed axtm 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.
Complete these tests expeditiously. Combining values from the two systems may result in non-conformance with the standard.
C39M – 16 – Compressive Strength of Cylindrical The effect of these differences may need to be considered or determined by supplementary testing for quality control or test result evaluation purposes.
The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other.
Work Item s – proposed revisions of this standard. Take care not to restrict the flow of concrete from the mixer, container, or transportation unit so as to cause segregation. In any case do not obtain samples until after all of the water and any admixtures have been added to the mixer; also do not obtain samples from the very first or last portions of the batch discharge Note 3.
Due to the difficulty of determining d172 actual quantity of concrete discharged, the intent is to provide samples that are representative of widely separated portions, but not the beginning and the end of the load. Referenced Documents purchase separately The documents listed below are referenced within the subject standard but are not provided as part of the standard.
It is the responsibility of the user of this standard to establish appropriate safety and health practices and qstm the applicability of regulatory limitations prior to use. Scrape any mortar adhering to the sides of the wet-sieving equipment into the batch. Smaller samples are not prohibited for routine air content, temperature, and slump tests. Historical Version s – view previous versions of standard.
Take the portions so obtained within the time limit specified in Section 4, and combine them into one composite sample for test purposes. Martins, Damasceno, Awada – Pronto-socorro Pronto-socorro: Combine the samples so obtained into one composite sample for test purposes. Approved October 1, Combining values from the two systems may result in non-conformance with the standard.