Slab Replacement Maturity Guidelines

This study investigated the use of maturity method to determine early age strength of concrete in slab replacement application. Specific objectives were (1) to evaluate effects of various factors on the compressive maturity-strength relationship of concrete at early age, (2) to develop appropriate test procedures for applying maturity method to predict early age strength of concrete, and (3) to validate the accuracy of the prediction of maturity method using the proposed test procedures. The maturity method using the Arrhenius maturity function was found to be quite reliable and convenient for use in predicting the early-age compressive strength of concrete in replacement slab application. Some limitations of maturity-strength prediction, such as the strength loss due to high curing temperature and insufficient moisture, supply were observed in the laboratory studies. However, these limitations were observed at the later age of the concrete when the compressive strength reached around 3,000 to 3,500 psi, and thus the observed limitations did not have any negative effect on the early-age-strength prediction of the concrete in the replacement slab. Using the strength of the protection specimens as strength determination of the in-place concrete is unreliable and may result in over-prediction of its strength. The maturity method using the Arrhenius maturity function is recommended for use to estimate the early-age compressive strength of concrete in slab replacement application. A testing protocol for the generation of maturity-strength curve for prediction of early-age compressive strength of concrete was recommended. The concrete used in the replacement lab must have exactly the same water-cement ratio, mix ingredients, and fresh concrete properties as those of the laboratory concrete used to develop the maturity curve. In the event that differences in fresh concrete properties, with more than ±1 inch in slump and/or ±1 % in air contents, are observed between the actual concrete used at the project site and the concrete which has been used to develop the maturity-strength curve, the maturity-strength curve should not be used to make strength predictions without proper adjustments of the predicted strengths due to effects of the variations in the fresh concrete properties.

Language

  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Appendices; Figures; Maps; Photos; References; Tables;
  • Pagination: 168p

Subject/Index Terms

Filing Info

  • Accession Number: 01526282
  • Record Type: Publication
  • Report/Paper Numbers: 00093785, U.F. Project No: 00098299
  • Contract Numbers: BDK75-977-62
  • Files: TRIS, ATRI, USDOT, STATEDOT
  • Created Date: May 28 2014 3:26PM