Rapid Strength Concrete for Transportation Structures and Pavements for Transportation Structures and Pavements International Conferences on Advances in Building Sciences and Rehabilitation and Restoration of Structures India, Madras, 2013 B. Stein Twining, Inc., USA R R R. Ryan CMT Research Associates, USA T. Kumar CMT Research Associates, India CMT Research Associates, India V. Perez CTS Cement, USA B. Stein, R. Ryan, T. Kumar, V. Perez
Challenging call for sustainability to the construction industry Volumes of consumption of natural materials for concrete; Duration of service life of structures and pavements; Necessity of limiting carbon dioxide footprint Necessity of limiting carbon dioxide footprint are used annually are used annually for complete rebuilding of for complete rebuilding of deteriorating concrete deteriorating concrete transportation infrastructure. transportation infrastructure. transportation infrastructure. transportation infrastructure. of of bridges, highways, city bridges, highways, city streets , etc. usually needed streets , etc. usually needed t t t t t t ll ll d d d d for repair and preservation for repair and preservation work complicates efficient work complicates efficient maintenance. maintenance. maintenance. maintenance. B. Stein, R. Ryan, T. Kumar, V. Perez
Change design & maintenance practices to enhance sustainability and reduce environmental impact… Extension of service life of structures and pavements; Design and implementation of repairable concrete structures and pavements; and structures and pavements; and Use of special for preservation & rehabilitation of structures & pavements allowing for and and . Rapid strength concrete has been Rapid strength concrete has been successfully used for maintenance, successfully used for maintenance, f ll f ll d f d f i i repair and extension of services life repair and extension of services life of: of: Bridges Bridges Bridges Bridges Tunnels Tunnels Airfields Airfields Highways Highways Cit Cit City streets City streets t t t t B. Stein, R. Ryan, T. Kumar, V. Perez
Accelerate construction by enhancing strength gain of cast-in-place concrete… Hydraulic cements intended for enhancing early age Hydraulic cements intended for enhancing early age strength gain; Non-chloride accelerators; Lower water-cementitious material ratio; Lower water cementitious material ratio; Enhance development of early-age bond of cement paste to coarse aggregate Increase initial temperature of concrete p Increase temperature of concrete during curing between Interstate Highway-5 & between Interstate Highway-5 & Highway-14, Los Angeles County, CA, Highway-14, Los Angeles County, CA, Highway 14, Los Angeles County, CA, Highway 14, Los Angeles County, CA, USA, November 2007. Rapid strength USA, November 2007. Rapid strength concrete was produced with Type III concrete was produced with Type III high-early Portland cement and high-early Portland cement and contained a non chloride accelerator contained a non chloride accelerator contained a non-chloride accelerator. contained a non-chloride accelerator. B. Stein, R. Ryan, T. Kumar, V. Perez
Compressive strength ≥ 17 MPa; Corresponding Flexural strength ≥ 2.8 MPa One hour plus when rapid hardening cements are used Two hours plus when Type III Portland cement with accelerators is used > 25,000 yd 3 (19,000 m 3 ) RSC with > 25,000 yd 3 (19,000 m 3 ) RSC with calcium sulfoaluminate (CSA) cement; calcium sulfoaluminate (CSA) cement; Performed night time, freeway closures Performed night time, freeway closures limited to 10 hours to minimize impact on limited to 10 hours to minimize impact on limited to 10 hours to minimize impact on limited to 10 hours to minimize impact on mobility; mobility; Satisfactory performance of the Satisfactory performance of the replacement pavement recorded for 10 replacement pavement recorded for 10 years and counting years and counting years and counting. years and counting. B. Stein, R. Ryan, T. Kumar, V. Perez
Rapid hardening cements – no accelerators required Rapid setting & hardening of binder (ASTM C1600) fast strength development of RSC. development of RSC Workability is achieved by using & . 80 70 60 a e strength, MPa 418 kg/m3 mix 390 kg/m3 mix 50 335 kg/m3 mix 279 kg/m3 mix 40 251 kg/m3 mix 251 k / 3 i Compressive Log. (418 kg/m3 mix) 30 Log. (390 kg/m3 mix) Log. (335 kg/m3 mix) 20 20 Log. (279 kg/m3 mix) Log. (279 kg/m3 mix) Log. (251 kg/m3 mix) 10 Development of Compressive Strength of Concrete with Calcium Sulfoaluminate Cement 0 0 1 10 100 1000 10000 Time, hours (logarithmic scale) B. Stein, R. Ryan, T. Kumar, V. Perez
RSC with Type III Portland cement – non-chloride accelerators must Approximately 46 to 59 mL accelerator per 1 kg of cement can yield compressive strength of 17 – 20 MPa or ; Very low w/cm is essential; and assist in providing needed workability. RSC with RSC with Type III Portland cement Type III Portland cement Non-chloride accelerator Non-chloride accelerator Non-chloride accelerator Non-chloride accelerator Superplasticizer Superplasticizer Hydration controlling Hydration controlling admixture admixture was first used in 2000 for full- was first used in 2000 for full- depth pavement replacement depth pavement replacement on State highway 405 in Culver on State highway 405 in Culver City, CA, USA. City, CA, USA. City, CA, USA. City, CA, USA. B. Stein, R. Ryan, T. Kumar, V. Perez
Transportation Structures – Typical Applications of RSC for Emergency and Planned Rehabilitation Application Min Strength Min Curing Materials & Proportions Requirement Time after Hydraulic Admixtures Max w/cm at the Time Completion of p Cement of Opening to Finishing, hours Service, MPa Bridge Decks 21 3 Rapid HRWR; SC; ~ 0.31-0.33 compressive hardening Latex Approach 8.5 1 Rapid HRWR; SC ~ 0.50-0.53 Structures compressive hardening 2 Portland HRWR; SC; ~ 0.32-0.34 Type III Accelerator Abbreviations: HRWR – high range water reducer g g SC – set controlling admixture B. Stein, R. Ryan, T. Kumar, V. Perez
Pavements – Typical Applications of RSC for Emergency and Planned Rehabilitation Application Min Strength Min Curing Materials & Proportions Requirement Time after Hydraulic Admixtures Max w/cm at the Time Completion of Cement of Opening to f O i Fi i hi Finishing, hours h Service, MPa Lean Concrete 5.0 (725 psi) 1 Rapid HRWR; SC ~ 0.55-0.60 Base compressive hardening 2 Portland HRWR; SC; ~ 0.32-0.34 Type III Accelerator Pavement 2.8 (400 psi) 1 Rapid HRWR; SC ~ 0.40-0.43 Course flexural hardening 2 Portland HRWR; SC; ~ 0.32-0.34 Type III Accelerator 3.8 (550 psi) 1.5 Rapid HRWR; SC ~ 0.38-0.39 flexural flexural hardening hardening 5 Portland HRWR; SC; ~ 0.32-0.34 Type III Accelerator Abbreviations: HRWR – high range water reducer SC – set controlling admixture B. Stein, R. Ryan, T. Kumar, V. Perez
RSC must be proportioned for Constructability… Property Performance Proportioning Notes Notes Notes Slump 4 to 8 inches HRWR Segregation Good Continuous aggregate grading resistance resistance Moderate to moderately low w/cm Moderate to moderately low w/cm Controlled addition rate of HRWR Optimized water content High fineness of hydraulic cement Retention of R t ti f 15 t 15 to 40 min 40 i S t Set controlling admixture t lli d i t workability after discharge Control of initial temperature of RSC Rate of bleeding Moderately low High fineness of hydraulic cements to low to low Low to moderately low w/cm is Low to moderately low w/cm is achieved by using HRWR 10 B. Stein, R. Ryan, T. Kumar, V. Perez
..must also account for durability & exposure conditions.. Property Performance Proportioning Notes Notes Permeability Permeability Lower than Lower than w/cm=0 32-0 45 is most common w/cm=0.32 0.45 is most common regular PCC Quicker hydration of cements and faster consumption of water, leaving less water for evaporation Higher rate of hydration of CSA cement Higher rate of hydration of CSA cement Sulfate resistance RSC can be CSA cement is high sulfate resistant specified for Type III PC can be specified and high sulfate produced for high sulfate resistance resistance i t w/cm=0.32-0.45 is most common / 0 32 0 45 i t Deleterious Can be Cements are available as low-alkali expansion due to mitigated CSA cement can be used with Class F the use of reactive fly ash for achieving the required y g q aggregates strength within 2-4 hours Abbreviations: PC – portland cement PCC – portland cement concrete PCC – portland cement concrete CSA – calcium sulfoaluminate (cement) 11 B. Stein, R. Ryan, T. Kumar, V. Perez
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