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Updating Thermal Data Sets to Better Evaluate Thermal Effects of Concrete

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Updating Thermal Data Sets to Better Evaluate Thermal Effects of Concrete DSO-2015-02 (8530-2016-01) Updating Thermal Data Sets to Better Evaluate Thermal Effects of Concrete Dam Safety Technology Development Program Katie Bartojay, P.E. Catherine Lucero, M.S., E.I.T U.S. Department of the Interior Bureau of Reclamation Technical Service Center Denver, Colorado January 2016 Form Approved REPORT DOCUMENTATION PAGE OMB No. 0704-0188 The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing the burden, to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE 2. REPORT TYPE 3. DATES COVERED 12-31-2015 Research n/a 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER n/a Updating Thermal Data Sets to Better Evaluate Thermal Effects of Concrete 5b. GRANT NUMBER n/a 5c. PROGRAM ELEMENT NUMBER n/a 6. AUTHOR(S) 5d. PROJECT NUMBER n/a Katie Bartojay, P.E. 5e. TASK NUMBER Catherine Lucero, M.S., E.I.T. n/a 5f. WORK UNIT NUMBER n/a 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT U.S. Department of the Interior NUMBER Bureau of Reclamation n/a Technical Service Center Concrete, Geotechnical, and Structural Laboratory 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR'S ACRONYM(S) U.S. Department of the Interior DSO Bureau of Reclamation 11. SPONSOR/MONITOR'S REPORT Dam Safety Office NUMBER(S) DSO-2015-02 (8530-2016-01) 12. DISTRIBUTION/AVAILABILITY STATEMENT No Restrictions 13. SUPPLEMENTARY NOTES 14. ABSTRACT The thermal behavior of concrete has long been studied to reduce cracking, especially in massive members, where heat generation is great. Heat dissipation and restraint create volume changes that can induce stresses at an early age, when strength and modulus are low. Many designers and contractors use Figure 31 of Reclamation Engineering Monograph (EM) No. 34 “Control of Cracking in Mass Concrete Structures” or Figure 4.1 of ACI 207.2R “Thermal and Volume Change Effects on Cracking of Mass Concrete” when preparing their temperature control plan for mass concrete. These figures were generated from pre 1960’s data and can be traced back to the 1936 Boulder Canyon studies. Due to changes in physical and chemical properties of cement over the years, these figures no longer provide accurate guidance to designers. In an effort to provide a reliable set of thermal properties, nine (9) concrete mixtures were tested for adiabatic temperature rise, diffusivity, conductivity and thermal expansion. This study includes mixtures containing various amounts of OPC, Class F fly ash, and Grade 100 Slag. 15. SUBJECT TERMS Mass concrete, thermal properties, adiabatic temperature rise 16. SECURITY CLASSIFICATION OF: 17. LIMITATION 18. NUMBER 19a. NAME OF RESPONSIBLE PERSON None OF ABSTRACT OF PAGES Katie Bartojay, P.E. U 35 a. REPORT b. ABSTRACT a. THIS PAGE 19b. TELEPHONE NUMBER (Include area code) U U U (303) 445-2374 Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std. Z39.18 U.S. Department of the Interior Bureau of Reclamation Technical Service Center Denver, Colorado January 2016 Updating Thermal Data Sets to Better Evaluate Thermal Effects of Concrete Dam Safety Technology Development Program DSO-2015-02 (8530-2016-01) prepared by Katie Bartojay, P.E. Catherine Lucero, M.S., E.I.T. DSO-2015-02 (8530-2016-01) Mission Statements The mission of the Department of the Interior is to protect and provide access to our Nation’s natural and cultural heritage and honor our trust responsibilities to Indian Tribes and our commitments to island communities. The mission of the Bureau of Reclamation is to manage, develop, and protect water and related resources in an environmentally and economically sound manner in the interest of the American public. ii DSO-2015-02 (8530-2016-01) BUREAU OF RECLAMATION Dam Safety Technology Development Program Concrete, Geotechnical, and Structural Laboratory, 86-68530 DSO-2015-02 (8530-2016-01) Updating Thermal Data Sets to Better Evaluate Thermal Effects of Concrete Cet-AW--f) Prepared: Catherine Lucero, M.S., E.I.T. Civil Engineer, Concrete, Geotechnical, and Structural Laboratory Group 86-68530 ecked: Bret Robertson, P.E. Civil Engine r, Concrete, Geotechnical, and Structural Laboratory Group 86-68530 Technic Approval: Katie ay, P.E. Civil E •ineer, Concrete, Geotechnical, and Structural Laboratory Grou 86-.8530 / Peer Review: Veronica Madera, P.E. Date Civil Engineer, Concrete, Geotechnical, and Structural Laboratory Group 86-68530 REVISIONS l l d d ica re va Date Description w ke a ro r ie hn v c Pee Re Prep Chec App Te 111 DSO-2015-02 (8530-2016-01) Contents Page Contents ................................................................................................................ iv List of Tables .................................................................................................... v List of Figures .................................................................................................. vi Abbreviations .................................................................................................. vii Acknowledgements ................................................................................................. Abstract .................................................................................................................... Introduction ........................................................................................................... 1 Cement Chemistry and Hydration Reactions .................................................... 1 Temperature Rise in Mass Concrete ................................................................. 2 Current Guidance for Evaluating Thermal Effects ........................................... 3 ACI Manual of Concrete Practice ............................................................... 3 Portland Cement Association ...................................................................... 6 Research Objective ........................................................................................... 7 Laboratory Study .................................................................................................. 8 Adiabatic Temperature Rise ............................................................................. 9 Thermal Properties .......................................................................................... 11 Specific Heat ............................................................................................. 11 Thermal Diffusivity .................................................................................. 12 Thermal Conductivity ............................................................................... 13 Coefficient of Linear Thermal Expansion ................................................ 14 Discussion of Laboratory Results ...................................................................... 16 Adiabatic Temperature Rise ........................................................................... 16 Thermal Properties .......................................................................................... 20 Recommendations for Estimating Heat Rise in Mass Concrete ..................... 21 Conclusions .......................................................................................................... 25 References ............................................................................................................ 26 Appendix A. Mill Certificates ....................................................................... 28 Appendix B. Adiabatic Temperature Rise Curves ..................................... 34 Appendix C. Temperature Rise from Savage et al. (1936) ........................ 40 Appendix D. Temperature Rise from Engineering Monograph 34 ...........42 Appendix E. Example Calculations ............................................................. 43 iv DSO-2015-02 (8530-2016-01) List of Tables Table 1. Enthalpy of complete hydration for major phases of cement. From Bentz et. al [4]. ........................................................................................................ 2 Table 2. Fineness and 28-day heat of hydration for various cement types. ........... 5 Table 3. Equivalent cement factors for common SCMs [11]. ............................... 6 Table 4. Chemical and physical properties of cementitious materials. .................. 8 Table 5. Summary of mixture proportions ............................................................. 9 Table 6. Summary of thermal properties, highlighted values are outside the range of recommended values from ACI ........................................................................ 15 Table 7. Comparison of calculated and measured 28-day temperature rise. ....... 19 Table 8. Comparison of calculated and measured temperature rise for previous Reclamation
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