Characterization of Portland Cement Concrete Coefficient of Thermal Expansion in South Carolina

The South Carolina Department of Transportation (SCDOT) sought to regionally calibrate specific input parameters used by the Mechanistic Empirical Pavement Design (MEPDG) software. These properties include the coefficient of thermal expansion (CTE), compressive strength, and unit weight of typical SC concrete mixtures. Additionally, splitting tensile strength was included in the experimental program. Laboratory produced mixtures were tested to identify the effective CTE value of the cement paste, sand, and coarse aggregate compotes typically used in SC concrete pavements. A 25 percent cement replacement of type F fly ash and a single source of natural sand was used in the mortar component of the concrete mixtures. A total three coarse aggregate sources were used in the form of no. 57 crushed stone product or a 75:25 blend of no. 57 and no. 789 crushed stone. The CTE values of the individual phases (i.e. cement paste, sand and coarse aggregates), and concrete mixtures were measured. The resulting CTE of paste and sand was 7.3 and 5.9×10ˉ⁶ in./in./°F, respectively. The CTE of three coarse aggregates ranged from 2.96 to 3.83×10ˉ⁶ in./in./°F. The range of average CTE values of the concrete was 4.82 to 5.32×10ˉ⁶ in./in./°F. The magnitude of the CTE values were shown not to be directly related to the compressive strength. Field cored specimens were also taken from a section of SC – 80 in Spartanburg county, SC, and analyzed. Three pavement slabs were arbitrarily selected along a 3.5-mi. pavement section. The targeted slabs were of the outside travel lane, with cores taken between the wheel paths at the leading end, middle, and trailing ends of each slab. There was not significant difference between the average CTE values of pavement slabs. The effective CTE of SC - 80 concrete pavement was determined to be 5.05×10ˉ⁶ in./in./°F. The compressive strength and unit weight properties of the SC – 80 specimens suggested that the laboratory produced concrete mixtures from the first part of this study were representative of the concrete pavements in South Carolina.

Language

  • English

Media Info

  • Media Type: Digital/other
  • Features: Appendices; Figures; Maps; Photos; References; Tables;
  • Pagination: 115p

Subject/Index Terms

Filing Info

  • Accession Number: 01640095
  • Record Type: Publication
  • Report/Paper Numbers: FHWA-SC-17-03
  • Contract Numbers: SPR 722
  • Files: NTL, TRIS, ATRI, USDOT, STATEDOT
  • Created Date: Jun 20 2017 9:05AM