Calibration of Temperature Measuring Device (ASTM Standard)

 Apparatus:

4.1 Container, shall be made of no absorptive material and large enough to provide at least 3 in {75 mm} of concrete in all directions around the sensor of the temperature measuring device; concrete cover must also be at least three times the nominal maximum size of the coarse aggregate.

4.2 Temperature Measuring Device, shall be capable of accurately measuring the temperature of the freshly mixed concrete to ± 1°F [±0.5°C] throughout a range of 30°to120°F [0° to 50°C]. The temperature measuring device shall require immersion of 3 in {75 mm} or less during operation.

4.3 Partial immersion liquid-in-glass thermometers (and possibly other types) shall have a permanent mark to which the device must be immersed without applying a correction factor.

4.4 Reference Temperature Measuring Device, shall be readable and accurate to ±0.5°F [0.2°C] at the verification points in 5.1. A certificate or report that verifies the accuracy shall be available in the laboratory for review. The certificate or report shall provide documentation that the reference standard used in the verification is traceable to NIST.

5. Calibration of Temperature Measuring Device   

5.1 Each temperature measuring device used for determining temperature of freshly mixed concrete shall be calibrated annually, or whenever there is a question of accuracy. This calibration shall be performed by comparing the readings of the temperature measuring device at two temperatures at least 30°F [15°C] apart.

5.2 Calibration of the temperature measuring device may be made in oil or other suitable baths having uniform density if provision is made to:

5.2.1 Maintain the bath temperature constant within 0.5°F [0.2°C] during the period of the test.

5.2.2 Have both the temperature and reference temperature measuring device maintained in the both for a minimum of 5 min before reading temperatures.

5.2.3 Continuously circulate the bath liquid to provide a uniform temperature.

5.2.4 Slightly tap thermometers containing liquid to avoid adhesion of the liquid to the glass if the temperature exposure is being reduced.

Apparatus:

4.1 Container, shall be made of no absorptive material and large enough to provide at least 3 in {75 mm} of concrete in all directions around the sensor of the temperature measuring device; concrete cover must also be at least three times the nominal maximum size of the coarse aggregate.

4.2 Temperature Measuring Device, shall be capable of accurately measuring the temperature of the freshly mixed concrete to ± 1°F [±0.5°C] throughout a range of 30°to120°F [0° to 50°C]. The temperature measuring device shall require immersion of 3 in {75 mm} or less during operation.

4.3 Partial immersion liquid-in-glass thermometers (and possibly other types) shall have a permanent mark to which the device must be immersed without applying a correction factor.

4.4 Reference Temperature Measuring Device, shall be readable and accurate to ±0.5°F [0.2°C] at the verification points in 5.1. A certificate or report that verifies the accuracy shall be available in the laboratory for review. The certificate or report shall provide documentation that the reference standard used in the verification is traceable to NIST.

5. Calibration of Temperature Measuring Device   

5.1 Each temperature measuring device used for determining temperature of freshly mixed concrete shall be calibrated annually, or whenever there is a question of accuracy. This calibration shall be performed by comparing the readings of the temperature measuring device at two temperatures at least 30°F [15°C] apart.

5.2 Calibration of the temperature measuring device may be made in oil or other suitable baths having uniform density if provision is made to:

5.2.1 Maintain the bath temperature constant within 0.5°F [0.2°C] during the period of the test.

5.2.2 Have both the temperature and reference temperature measuring device maintained in the both for a minimum of 5 min before reading temperatures.

5.2.3 Continuously circulate the bath liquid to provide a uniform temperature.

5.2.4 Slightly tap thermometers containing liquid to avoid adhesion of the liquid to the glass if the temperature exposure is being reduced.

Standard Test Method for Temperature of Freshly Mixed Portland Cement Concrete

 

Scope

This test method covers the determination of temperature of freshly mixed Portland cement concrete.

The values stated in inch-pound or SI unit are to be regarded separately as standard. Within the text, SI unit are show in brackets. The values stated in each system are not exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.

This standard does not purport to address all of the safety concerns, if any, associated with its use. 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.

Referenced Documents

ASTM Standards:

C 172 Practice for Sampling Freshly Mixed Concrete

Significance and Use

This test method provides a means for measuring the temperature of freshly mixed concrete. It may be used to verify conformance to a specified requirement for temperature of concrete.

Concrete containing aggregate of a nominal maximum size greater than 3 in. [75 mm] may require up to 20 min for the transfer of heat from aggregate to mortar. (See ACI Committee 207. IR Report)   

AASHTO, ASTM, BS Standard Code

Test Description	Applicable Standard
Sieve Analysis	AASHTO  T88  &  M124 , AASHTO T27 and T11,BS 1377: part 2 test 9.2
Liquid Limit	AASHTO T89
Plasticity Index PI	AASHTO T90
CBR	AASHTO T193 ,BS 1377 part 4 test 16 ,  (ASTM D 1883)
FDT	AASHTO T191 ,BS 1377 part 9 test  2.2
Maximum Dry Density	AASHTO T180
Sand Equivalent	AASHTO T176,ASTM C-88
Loss by Abrasion	AASHTO T96
Soundness(Sodium)	AASHTO T104
Soundness(Magneseum)	AASHTO T104
Ave. Compressive Strength	BS 1881
Mean water absorption of cubes	BS EN 1340
Rate of Application	ASTM D2995
Absorption	AASHTO T85
Specific Gravity	AASHTO T85
Marshall Properties
Number of compaction blows each end of specimen by freely held marshall hammer	AASHTO T-245
Stability(Marshall) Minimum ,Kg
Flow(Marshall),mm
Stiffness Minimum Kg/mm (minimum)
Percent air void in Mix
Percent air void in mineral aggregates, minimum % (V.M.A.)
Percent voids filled with asphalt cement %
Bitumen Content %
Loss of Marshall Stability by submerging specimen in water at 600C for 24hrs. As compared to stability measured after submersion in water at 600C for 30 mins.
Residual voids in total mix after 300 blows each end of specimen
Filler to Bitumen ration
Compaction of laid Asphalt Concrete	AASHTO T-166
Thickness laid Asphalt Concrete	AASHTO T-166
Slump	ASTM C-143 /AASHTO T 119M
Concrete Temperature	ASTMC-1064/BS 1881-130/ASTM 1064/M -99
Compressive Strength @ 7 & 28 Days	BS 1881
Water Absorption@ 28D	BS 1881-122:2011
Rapid Chloride Permeability @ 28D	AASHTO T277/ASTM C-1202
Water penetration@ 28D	DIN 1048-5:1991-06.
Initial Surface Absorption test(ISAT)@28D	BS 1881-208:1996
Shrinkage Test at @ 28D	BS 1881-122:2011

 

REFERENCE DOCUMENTS For AASHTO T-191

AASHTO Standards:

M231, Weighing Devices Used in the Testing of Materials.

T19M/T 19, Bulk Density (“Unit Weight”) and Voids in Aggregate.

T99, Moisture-Density Relations of Soils Using a 2.5kg (5.5-lb) Rammer and a 305-mm (12- in) Drop.

T127, Determination of Moisture in Soils by Means of a Calcium Carbide Gas Pressure Moisture Tester.

T265, Laboratory Determination of Moisture Content of Soils.

ASTM Standards:

D4643, Standard Test Method for Determination of Water Content of Soil by Microwave Oven Heating.

D4959, Standard Test Method for Determination of Water Content of Soil by Direct Heating.

E29, Standard Practice for using Significant Digits in Test Data to Determine Conformance with Specification.

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