Inspection and Testing of Ready Mix Concrete

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Inspection and testing of ready mix concrete is crucial to ensure that all specified conditions meet the acceptable criteria. Ready mix concrete, which produced in batching plant and transported to construction site by truck mounted mixers, are commonly inspected and tested in accordance with applicable standards such as ASTM international.

Inspect Ready Mix Concrete

Batching Plant Inspection

  • Firstly, examine and specify whether facilities, scales, and truck mixers meet the specified project requirements or not.
  • Inspect storage areas of all materials like cement, aggregate, and admixtures to ensure their cleanness, free of contamination, and properly protect materials from effect of freezing.
  • Inspect and verify that coarse and fine aggregate gradation tests are conducted in accordance applicable standards like ASTM C 136, and result reach project requirements.

Onsite Inspection of Ready Mix Concrete

Testing Ready Mix Concrete 

1. Onsite Tests

There are certain types of tests that shall be conducted on ready mix concrete upon reaching construction sites. Table 1 provide lists of tests that need to be performed on ready mix concrete on project site.

Table 1 Tests conducted on ready mix concrete upon reaching construction site

Type of tests ASTM international for testing procedures Test frequencies  Purpose of the test
Slump ASTM C 143/C 143M First truck load, whenever the consistency of the concrete appears to vary. Measure fresh concrete consistency, check its workability, and use as an indicator of poor mixed batch
Air content ASTM C 173, ASTM C 231 Performed on all samples taken to measure concrete strength To check air entrained concrete
Temperature ASTM C 1064 At the time of sampling for each strength test to make sure that concrete comply with certain specifications that define a certain allowable temperature range
Density ASTM C 138, ASTM C 567 Whenever required by project specifications To estimate concrete density
slump test on first batch of ready mix concrete
Fig. 3: slump test on first batch of ready mix concrete

2. Laboratory tests

There are certain properties that required to be evaluated. For this purpose, concrete specimen of ready mix concrete is tested in the laboratory. Table 2 provide list of tests needed to be performed for ready mix concrete.

Table 2 laboratory tests conducted on ready mix concrete specimens

Type of tests ASTM international for testing procedures Test frequencies  Purpose of the test
compressive strength ASTM C 39/C 39M Minimum two specimens are test at each age To estimate concrete compressive strength and determining conformance with the specified strength
Flexural strength ASTM C 78 or ASTM C 293 To estimate concrete flexural strength and determining conformance with the specified strength
Test results shall be compared with values provided in ACI 318/318R to find out whether the concrete confirm with specifications or not.

Sampling of Ready Mix Concrete

Curing and Handling Specimens

  • Samples, which casted for acceptance testing purposes, should be stored and cured for up to 48hr after molding on project site.
  • Curing specimen should be according to applicable standards like ASTM C 31/C 31M.
  • Specimens shall be stored in temperature ranges 16 to 27 ºC.
  • Loss of temperature or damages of specimens shall be prevented
  • Specimens shall be transported within 16 to 48 hours after molding to laboratory, and transportation time should not be longer than 4 hours.



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