AASHTO T 336:15(2019) Standard Method of Test for Coefficient of Thermall Expansion of Hydraulic Cement Concrete

AASHTO T 336:15(2019) Standard Method of Test for Coefficient of Thermall Expansion of Hydraulic Cement Concrete. This test method covers determination of the coefficient of thermal expansion (CTE) of hydraulic cement concrete cores and cylinders. Because it is known that the degree of saturation of concrete influences its measured coefficient of thermal expansion, the specimens must be in a saturated condition for this procedure. The values stated in SI units shall be regarded as the standard. REFERENCED DOCUMENTS AA SIITO Standards: • R 39, Making and Curing Concrete Test Specimens in the Laboratory • T 22M/T 22, Compressive Strength of Cylindrical Concrete Specimens • T 23, Making and Curing Concrete Test Specimens in the Field • T 24M1T 24, Obtaining and Testing Drilled Cores and Sawed Beams of Concrete 2.2. ASTM Standards: • C670. Standard Practice for Preparing Precision and Bias Statements for Test Methods for Constniction Materials • E228, Standard Test Method for Linear Thermal Expansion of Solid Materials with a Push-Rod Dilatometer • E289. Standard Test Method for Linear Thermal Expansion of Rigid Solids with Interferometry SUMMARY OF TEST METHOD This method determines the CTE of a cylindrical concrete specimen, maintained in a saturated condition, by measuring the length change of the specimen due to a specified temperature change. The measured length change is corrected for any change in length of the measuring apparatus (previously determined), and the CTE is then calculated by dividing the corrected length change by the temperature change and then the specimen length, as described in the section on calculations. 4. SIGNIFICANCE AND USE 4.1. Measurement of the CTIi permits assessment of the potential for length/volume change of concrete due to a uniform temperature change and of the potential deformation of a concrete structure due to a temperature gradient through the concrete. As an example, for pavement slabs on grade. uniform temperature change will affect the openings at joints and a temperature gradient through the thickness of these same slabs will produce curling of the slabs. The results of this test can be used to better estimate slab movement and stress development due to temperature change. 5. APPARATUS 5.1. concree Saw—Capable of sawing the ends of a cylindrical specimen perpendicular to the axis and parallel to each other. 5.2. Balance—A scale or balance having a capacity of 20 kg (44 lb) and an accurateness of 0.1 percent over its range. 5.3. caliper—Comparator or other...