Enhancing Early-Age Concrete Strength Through
Enhancing Early-Age Concrete Strengththrough NanotechnologyPittsburgh ACI Area Chapter MeetingWednesday, December 4, 2019
AIA Registered Course No. ASNano001BASF Construction Chemicals (J152) is a Registered Provider with The American Institute ofArchitects Continuing Education Systems. Credit earned on completion of this program will bereported to CES Records for AIA members. Certificates of Completion for non-AIA members areavailable on request.This program is registered with the AIA/CES for continuing professional education. As such, itdoes not include content that may be deemed or construed to be an approval or endorsement bythe AIA of any material of construction or any method or manner of handling, using, distributing,or dealing in any material or product. Questions related to specific materials, methods, andservices will be addressed at the conclusion of this presentation.2
DescriptionThis course will cover the basics of cement hydration andstrength development in concrete, the need for early-agestrength enhancement, and options available to increaseearly-age strength, including the use of nanotechnologybased admixtures.Applications highlighting the successful use ofnanotechnology-based strength-enhancing admixtures willalso be presented.3
Learning ObjectivesUpon completing this course, you will:understand the basics of the hydration of portland cement, itseffect on strength development and the need for enhancedearly-age strength in some concrete applications;know the different options available for early-age strengthenhancement;understand how nanotechnology-based strength-enhancingadmixtures function;learn about the use of nanotechnology-based strengthenhancing admixtures in various concrete applications.4
OutlineBasic overview of portland cement hydration and thefactors that affect strength developmentEnhanced early-age strength developmentWhy needed and typical optionsNanotechnology-based strength-enhancing admixturesTechnology and applicationsSummary5
Concrete As We Know It A Mixture of: Cementitious Materials Portland Cement Supplementary Cementitious Materials(SCMs) Fine & Coarse Aggregates Water Admixtures Fibers6
Hydration of Portland CementPortland CementC-S-H gel Ca(OH)2 Other WaterHydrationThe crystallization of C-S-Hoccurs close to the surfaceor onto the surface itselfcreating a layer which slowsdown the diffusion ofproducts and reactants(topochemical reaction)7HydrationAfter 28 days, thepenetration of thegranule hydration isabout 4 microns, andafter one year 8 microns.
Hydration of Portland Cement8Fig. 1 from second module: Instructional Modules inCement Science (Penn State, 1985)
Strength Development is Influenced By Cementitious materials content Portland cement type and amount SCM type and amountWater-cementitious materials ratio (w/cm)Temperature Ambient and concreteAdmixtures Set-control, otherCuring9
Biggest Influencers on Early Strength DevelopmentCement Type &Amount; SCMs10w/cmAmbient &ConcreteTemperaturesChemicalAdmixturesCuring
OutlineBasic overview of portland cement hydration and thefactors that affect strength developmentEnhanced early-age strength developmentWhy needed and typical optionsNanotechnology-based strength-enhancing admixturesTechnology and applicationsSummary11
Enhanced Early-Age Strength DevelopmentTypically needed to meet Specification requirements ex. time-to-opening, etc. Operational requirements precast / prestressed concrete Construction needs form stripping post-tensioning fast-track applications12
Enhanced Early-Age Strength Development: Typical OptionsIncreased portland cement content Reduced SCM contentType III cementLower w/cm with high-range water-reducing admixturesHigher initial curing temperature Heat (steam)Admixtures Accelerating admixtures13
Enhanced Early-Age Strength Development: Cement ContentIncreased portlandcement content Higher strength at all ages Increased heat of hydration Higher carbon footprint14Reference Mix: 564 lb/yd3 portland cement; 305 lb/yd3 water; nonair-entrained
Enhanced Early-Age Strength Development: Type III CementType III Portland cement Higher strength at all ages Increased heat of hydration Higher carbon footprint15Mix Info: 750 lb/yd3 portland cement; 0.38 w/c; nonair-entrained; PCE HRWR
Enhanced Early-Age Strength Development: Water ContentLower mix watercontent Higher strength at all ages HRWR required to achievetarget slump Increased mix stickiness16Reference Mix: 564 lb/yd3 portland cement; 305 lb/yd3 water; nonair-entrained
Effect of Temperature on Strength DevelopmentBoth early and later age compressive strength areinfluenced by the concrete and curing temperaturesGreater impact on early-age strength developmentHot weather and cold weather concreting practicesMaturity – degree hours relationship to compressivestrength17
Enhanced Early-Age Strength Development: Accelerating AdmixtureIncreasing acceleratingadmixture dosage Higher strength early ages Increased heat of hydration Shorter time-of-set18Reference Mix: 564 lb/yd3 portland cement; 305 lb/yd3 water; nonair-entrained
OutlineBasic overview of portland cement hydration and the factorsthat affect strength developmentEnhanced early-age strength developmentWhy needed and typical optionsNanotechnology-based strength-enhancing admixturesTechnology and applicationsSummary19
Nanotechnology DefinedNanotechnology is the understanding and control of matterat the nanoscale, at dimensions between approximately 1and 100 nanometers, where unique phenomena enablenovel applications.20Source: https://www.nano.gov/nanotech-101/what(Official website of the United States National Nanotechnology Initiative)
Nanotechnology DefinedNanotechnology Addressing ‘big problems’ with ‘tiny solutions.’ In 2006, ASTM International Committee E56 onNanotechnology approved its first standardnanoparticle, n — in nanotechnology, a sub-classificationof ultrafine particle with lengths in two or three dimensionsgreater than 0.001 micrometer (1 nanometer) and smallerthan about 0.1 micrometer (100 nanometers) and whichmay or may not exhibit a size-related intensive property.21Source: ASTM - E 2456, Terminology for Nanotechnology
Scale of Things – Nanometers and MoreHow big is a nanometer?It is a million times smaller than the smallestmeasurement you can see on a tape measure!A millionth of a millimeter Human Hair 50,000 to 150,000 nm22
Historical Use of Nanotechnology to Improve Concrete PerformanceCarbon NanotubeNanoparticles 40-80 nm23Titanium Dioxide (TiO2)Nanoparticles 4-8 nmPortland Cement 20,000 to 45,000 nm(for reference)
Carbon NanotubesCarbon Nanotubes are incredibly strong hollow strings ofcarbon atoms that bond together in a tubeCarbon Nanotubes can be added to concrete in a similarfashion to the way steel reinforcement is used in modernconstruction, greatly increasing the structural strength24
Titanium Dioxide (TiO2) NanoparticlesTitanium Dioxide occurs in nature as theminerals rutile, anatase, and brookite. Theseoxides are the source of commercial titaniumDue to its brightness and high refractive index,TiO2 is a widely used white pigmentApproximately four million tons of pigmentaryTiO2 are consumed annually worldwideNot all TiO2 are in nanoparticle formApplications include paints, coatings, plastics,foods, medicine, toothpaste portlandcement, and self-cleaning concrete** Photocatalytic type25
Nanotechnology to Improve Concrete Performance: What’s New?C-S-H Nanoparticles 50 to 100 nmPortland Cement 20,000 to 45,000 nm(for reference)26Human Hair 50,000 to 150,000 nm(for reference)
Portland Cement Hydration Process: What If?Suspended C-S-HnanoparticlesWhy wait for the crystallization of the nuclei tobe formed if C-S-H nanoparticles can beadded to the concrete mixture?27
Time to Innovate The challenge is how to introduce nanoscale particles intoconcrete – the best option is to use a liquid admixture!C-S-H nanoparticles28
Jump-Starting the Hydration ProcessCalcium SilicateHydrate Gel(C-S-H)Why wait for the crystallization of thenuclei to be formed if we can addthem?Crystalline CalciumSilicate Hydrate(C-S-H) nanoparticles31
Master X-Seed 55:Increase the Speed of Constructionhttps://youtu.be/6qLXzs9M-iI32
C-S-H Nanoparticle-Based Admixtures: Calorimetry DataRate of heat evolution, W/kg 022Hydration time, hours24Ref. with GU Type I/II cement & slag650 mL/100 kg (10 fl. oz/cwt) CSH-admixture with GU Type I/II cement & slag650 mL/100 kg (10 fl. oz/cwt) CSH-admixture with GU Type I/II cement & slag, 30 kg/m3 (50 lb/yd3) CM reduction33
Strength-Enhancing Admixture (SEA)Increases Early-Age Compressive Strength34(Nominal cementitious materials content of 611 lb/yd3 [362 kg/m3] with 20 percent fly ash, w/cm of 0.47;CSH-based Strength-Enhancing Admixture dosage of 10 fl oz/cwt [650 mL/100 kg])
Strength-Enhancing Admixture (SEA)Permits Reduction in Cementitious Materials ContentReferenceCSH-Based SEATotal Binder Content705 lb/yd3(418 kg/m3)629 lb/yd3(373 kg/m3)Fly Ash25 percent25 percentLimestone Powder21 percent21 percent0.390.40--7.3 fl oz/cwt(475 mL/100 kg)w/cmCSH-Based SEA35
Strength-Enhancing Admixture (SEA)Permits Reduction in Cementitious Materials Content36Control: Total binder content - 705 lb/yd3 [418 kg/m3] with 25% fly ash, 21% limestone powder, 0.39 w/cm;C-S-H Admixture: Dosage of 7.3 fl oz/cwt [475 mL/100 kg], Total binder content - 629 lb/yd3 [373 kg/m3] with25% fly ash, 21% limestone powder, w/cm of 0.40
Strength-Enhancing Admixture (SEA)Compressive Strength Increase, %Offers Potential for Increased Replacement of Portland Cement706050595552403037323434242010030% fly ash, w/p 0.5140% fly ash, w/p 0.5150% fly ash, w/p 0.40SEA dosage: 11.5 mL/kg7.5 fl oz/cwtSEA dosage: 11.5 mL/kg7.5 fl oz/cwtSEA dosage: 8.2 mL/kg5.3 fl oz/cwt1 day37377 day28 dayCementReduction &Higher Fly AshAmounts
Strength-Enhancing Admixture (SEA)Compressive Strength Increase, %Offers Potential for Increased Replacement of Portland Cement7060656150454030242010065% slag cement, w/p 0.45SEA dosage: 19.2 mL/kg12.5 fl oz/cwt1 day3831287 day35% limestone powder, w/p 0.40SEA dosage: 19.2 mL/kg12.5 fl oz/cwt28 dayCement Reduction & HighAmounts of Slag Cement orLimestone Powder
C-S-H Nanoparticle-Based Admixtures: Typical Applications39Precast ConcreteCast-in-Place Concrete Reduce cycle times Expedite construction Enhance product aesthetics Optimize concrete mixture to reduce carbon footprint
Strength-Enhancing AdmixturePotential Benefits in Concrete Pipe Production40
Benefits in Production of Concrete PipeMix Cost Reduction: Permits reduction of cementitious materials content,normally eliminating surfactant admixtures without strength reduction, whileimproving pipe appearance.Inventory Reduction Flexibility: Reduces duration of storage in the productionyard until 80% of the design strength is achieved.Reduction in Post-Production Defects: Higher early strengths reduce potentialfor chipping or cracking when the pipes are moved.Mixture Simplification: Makes it possible to meet strength requirements for bothClass 3 and Class 5 pipes with only one mixture proportion.Improved Aesthetics: Enhances surface appearance.Energy Savings: Offers potential to either reduce or eliminate heat curing.41
Improved Surface AppearanceReference PipesWith C-S-H Nanoparticle-BasedStrength-Enhancing Admixture42
Improved Surface Appearance43
Tilt-Up ConstructionStripping and Lifting Considerations from the Concrete PerspectiveFaster development ofconcrete strength tofacilitate construction44
Construction in the 21st Century Owners / Design Team often ask:“Do your productsaddress mysustainabilityrequirements?”45?
BASF EPD for Concretehttps://youtu.be/1492bds3UEY46
Nutrition labels provide information on health impacts from foodwhile an EPD 47
Sustainability Benefits ofNanoparticle CSH-Based SEAscan be Quantified with EEA
Sustainability Benefits of CSH Nanoparticle-Based AdmixtureOverall reduction in environmental footprint
Pier 27 Residential Building - Toronto, Canada35-storey residential building completedSummer 2019; 32,700 yd3 (25,000 m3) of concrete;3,900 yd3 (3,000 m3) of concrete optimizedto achieve high-early strength in 16 – 18 h; lower cementitious materials contentworkable and pumpable; slump loss minimizedWill receive the “Material Development &Innovation Award” from Ontario ConcreteAwards in Dec. 2019.50
OutlineBasic overview of portland cement hydration and thefactors that affect strength developmentEnhanced early-age strength developmentWhy needed and typical optionsNanotechnology-based strength-enhancing admixturesTechnology and applicationsSummary51
C-S-H Nanoparticle-Based Admixtures: SummaryIncreased desire for sustainable offeringsdrives innovationsTechnology exists to solve ‘big problems’with ‘tiny solutions’Challenge is to effectively deliver anddistribute small particles into concreteLiquid chemical admixture technologyoffers such a pathway to delivery
C-S-H Nanoparticle-Based Strength-Enhancing Admixtures (SEAs)Admixtures Contain C-S-H Seeds Strength-enhancing admixtures containnanoparticles Nanoparticles provide C-S-H ‘seeding’Unmatched Strength Enhancement C-S-H nanoparticles improve cement hydration Increase early- and late-age strength developmentValue to Producers & Engineers C-S-H nanoparticles allow for design flexibility Facilitates mixture optimization and cementreduction without strength loss53Cryo-SEM imaging shows crystalgrowth between cement grains inearly stages of hydration
150 yearsThank You!This concludes the Continuing Education Program.Additional courses:www.master-builders-solutions.basf.us54
55
For additional information or questions:Phone:(800) 628-9990Email:admixtures@basf.comWeb page: www.master-builders-solutions.basf.us 2019 BASF Corporation.The material contained in this course wasresearched, assembled, and produced by BASFCorporation and remains their property. Questionsor concerns about this course should be directed tothe instructor.56
Dec 04, 2019 · admixture dosage Higher strength early ages Increased heat of hydration Shorter time-of-set. Enhanced Early-Age Strength Development: Accelerating Admixture . Reference Mix: 564 lb/yd. 3. po
Chapter 3 3.1 The Importance of Strength 3.2 Strength Level Required KINDS OF STRENGTH 3.3 Compressive Strength 3.4 Flexural Strength 3.5 Tensile Strength 3.6 Shear, Torsion and Combined Stresses 3.7 Relationship of Test Strength to the Structure MEASUREMENT OF STRENGTH 3.8 Job-Molded Specimens 3.9 Testing of Hardened Concrete FACTORS AFFECTING STRENGTH 3.10 General Comments
For American code ACI 318-11 [10], the shear strength of concrete is given by: (1) P is the axial compression load, A g is the gross area of the section, and fc is the concrete cylinder compressive strength (MPa). For Egyptian code ECP-203 [11], the concrete shear strength v C is given as a function of concrete cube compressive strength (f cu .
the concrete tensile strength is known than when only the concrete compressive strength is known. Courtois lists an area of future research: “In mass concrete structures, we must learn more about the ultimate tensile strength of concrete at very early ages. Forms are usually reanchored to a previous lift at ages of 48 to 72 hr and safe anchorage
the strength of concrete the lower its ductility. This inverse relation between strength and ductility is a serious drawback for the use of higher-strength concrete, and a compromise between these two char-acteristics of concrete can be obtained by adding discontinuous fibers. Addition of fibers to concrete makes it more homogeneous and iso-
concrete and early strength using artificial neural network [2]. The Intelligent Prediction system of concrete strength was developed, to provide strength information for removal of form work and scheduling the construction [3]. The split tensile strength and percentage of water absorption of concrete containing TiO 2 nanoparticles
overlay that could be opened as quickly as possible to traffic. Three different concrete overlays placed on the experimental bridge were compared; the LMC-VE, plus a Latex Modified Concrete High Early strength (LMC-HE, using Type III cement that would gain strength in 24-48 hours) and MoDOT's normal Type B2 bridge deck concrete
Concrete Beams 9 Lecture 21 Elements of Architectural Structures ARCH 614 S2007abn Reinforced Concrete - stress/strain Concrete Beams 10 Lecture 21 Elements of Architectural Structures ARCH 614 S2007abn Reinforced Concrete Analysis for stress calculations steel is transformed to concrete concrete is in compression above n.a. and
AutoCAD 2000, 2000i & 2002 System Variables Highlighted numbers are preferred or standard Variables pertain to all versions except where noted (200XX) System Variable Command(s) affected _PKSER Environment (Read-only) Type: Integer Saved in: Registry Returns the serial number assigned to AutoCAD ACADLSPASDOC TOOLS/OPTIONS Type: Integer Saved in: Registry Initial value: 0 Controls whether .
