5th Pan American Conference for NDT 2-6 October 2011, Cancun, Mexico. Scanning Electron Microscopy to Examine Concrete with Carbon Nanofibers
|
|
- Rosa Murphy
- 6 years ago
- Views:
Transcription
1 Scanning Electron Microscopy to Examine Concrete with Carbon Nanofibers Shane M. PALMQUIST 1, Edward KINTZEL 2, Keith ANDREW 2 1 Department of Engineering, Western Kentucky University; Bowling Green, Kentucky, United States Phone: , Fax: ; shane.palmquist@wku.edu 2 Department of Physics & Astronomy, Western Kentucky University; Bowling Green, Kentucky, United States Phone: , Fax: ; edward.kintzel@wku.edu, keith.andew@wku.edu Abstract Mechanical properties of concrete are most commonly determined using destructive tests including: compression, flexure, and fracture notch specimen tests. However, nondestructive tests exist for evaluating the properties of concrete such as ultrasonic pulse velocity and impact echo tests. One of major issues with concrete is that unlike steel it is quasi brittle material. It tends to want to crack when tensile stresses develop. These cracks generally develop at the interfacial transition zone, ITZ, between the cement paste and the aggregate. Fibers have been added to concrete for many years to help with temperature and shrinkage cracks. In more recent years, the concepts of adding fibers with enhanced properties such as carbon nanofibers, CNFs, to concrete have been explored. Some possibilities include developing concrete that may be more durable, flexible, stronger, less permeable, and potentially crack free than traditional concrete. Based on SEM images and quantitative data from the literature, this paper examines the ITZ of concrete made with CNFs. Results provide greater understanding on the nature of the ITZ region in concrete made with CNFs. Keywords: Concrete, cementitious materials, fibers, carbon nanofibers (CNFs), interfacial transition zone (ITZ) 1. Introduction For many years, fibers have been added to concrete mixes in low volume dosages for the purposes of reducing plastic shrinkage cracking [1]. However, they do not significantly affect the free shrinkage of concrete nor do they provide increased ductility. Of particular importance is the understanding and interaction of small fibers with the cementitious mix at the micro and nanoscales. Figure 1 shows the surface of a cementitious material at the micron level, which was taken at Western Kentucky University by a Large Scanning Electron Microscope, LSEM. This LSEM is one of only two in the world that are capable of testing full size members and specimens. In the figure, darkened regions throughout indicate locations of potential microcracks, voids and areas of higher porosity. Connecting more structured regions to other weaker regions can improve the performance of concrete. Adding fibers at the smaller scales and in greater volume dosages can have an impact at the macroscale in terms of crack lengths, crack widths, degree of spalding, and crack pattern [2]. Many factors affect the performance of fibers in concrete and cementitious materials. These include: fiber material, fiber length, fiber diameter, surface texture of the fiber, fiber orientation in the cementitious composite, fiber distribution in the composite, and bond between the fiber and the composite. While any one factor may have a significant effect on the composite performance, bond is critical. 2. Fibers in Concrete 2.1 Fiber Bond 5th Pan American Conference for NDT 2-6 October 2011, Cancun, Mexico Developing a compatible bond between the fibers and the cementitious material is crucial to improving the properties of the concrete. If a perfect bond or overly strong bond develops
2 between the fibers and the cementitious material, the resulting concrete will not perform well. Fibers in the concrete should bridge the crack widths that form and close them as they try to develop and open. A near perfect bond results in a highly localized strain in a very small region of a fiber causing it to potentially break prematurely. Likewise, if a poor bond or overly weak bond develops between the fibers and the cementitious material, the resulting concrete will not perform well either. The fibers, which bridge the crack widths, will not get activated when cracks develop and open. Fiber pull-out will result. Figure 2 shows the bottom side view of a four point bend test where a good bond between the fibers and the composite developed. As soon as a crack appeared and began to grow, the bridging microfibers closed the crack. Afterward another crack appeared and was closed. This repeated until final failure occurred in a dominating crack. In this case, adding compatible microfibers improved the ductility of the concrete [3]. Figure 1. SEM image of the surface of a cementitious material Figure 2. Four point bend test showing multiple cracks on underside
3 2.2 Fiber Dispersion Fiber distribution refers to the ability of the fibers to evenly disperse in the cementitious mix. Failure of the fibers to properly disperse evenly throughout the mix results in fiber clumping. Clumping can severely weaken the strength of the overall material and cause the concrete to be inhomogeneous. Random pockets of clumped fibers will result in voids. Fiber distribution is generally handled at the product level, where fibers are engineered to segregate evenly into the concrete upon being added to the mix. However, verification is required and should not be assumed. 2.3 Carbon Nanofibers Failure of concrete materials is caused by microcracks that propagate and grow. These cracks often occur much earlier and can only be observed at the nanoscale [4]. Carbon nanofibers, CNFs, have many advantages as a reinforced material for cements as compared to traditional fibers. CNFs have superior tensile strengths (ranging from 10 to 63 GPa) compared to other types of traditional fibers. This can improve the mechanical properties of the concrete. CNFs have very small diameters which can be distributed more widely in the concrete with reduced fiber spacing than traditional larger fibers. CNFs have very high length-to-width ratios, requiring significantly higher energies for crack propagation around the fibers. Figure 3 shows CNFs bridging a crack [4]. However, proper dispersion of CNFs in concrete is critical. 3. Interfacial transition zone 2.1 Wall effect Figure 3. CNFs bridging a crack [4] Concrete and cementitious materials generally consist of two distinctly different regions, the cement paste and the aggregate. Fibers act like a specialized aggregate and only occupy a very small portion of the total volume. In general, there is a tendency to assume that the properties of the cement paste and the aggregate in the mix are unaffected by the presence of
4 the other. However, the presence of the two in the mixture will result in an interaction between them that corresponds to a negative impact on the performance of the hardened concrete material. Cement particles in fresh concrete cannot efficiently pack together when they are in close proximity of larger solid objects, such as aggregates or fibers. However, much smaller cement and fibers associated with micro and nano materials may potentially improve this. The potential packing problem due to size compatibility is generally referred to as the wall effect. For typical concrete with normal sized aggregates and common temperature and shrinkage fibers, this effect is magnified by the shearing stresses exerted on the cement paste by the aggregate and fibers during the mixing process, which tend to cause the water to separate from the cement particles near the surfaces of the aggregate and fibers. The result is a narrow region surrounding the aggregate and fibers with fewer cement particles, and thus more water. This region is often called the interfacial transition zone (ITZ). Due to the varying types, amounts and sizes of the components in concrete materials as well as the mixing and casting processes involved, the ITZ are not specific zones but are regions of transition. The formation of the ITZ also occurs along mold interfaces since the mold itself acts like a very large aggregate as compared to the cement paste. Figure 4 shows the ITZ regions around all aggregates, fibers and mold faces. ITZ around aggregate Cement paste Aggregate ITZ along face of mold ITZ around fiber Fiber ITZ along face of mold Figure 4. Cementitious material showing ITZ regions 2.2 ITZ properties The ITZ is a region with a higher w/c ratio than the cement paste, and thus a higher porosity than the cement paste. The ITZ region is not uniform but varies by location as the distance away from the surface of the aggregate or fiber increases as shown in Figure 5 [5]. In this figure, the aggregate is shown on the left. Thin white lines running vertically in this figure indicate distances of 20 and 50 µm from the surface of the aggregate. As mentioned earlier and as seen in Figure 5, the ITZ is not a region but a zone of transition. There is no discrete boundary between the ITZ region and the cement paste. The size of the ITZ region is generally believed to be 15 to 20 µm in size [5,6]. The size of the ITZ region tends to be
5 larger around larger aggregates and fibers and smaller around smaller aggregates and fibers. Because of the larger pores, the ITZ regions are characterized by the presence of larger crystals, particularly of calcium hydroxide, CA(OH) 2, than are found in the cement paste. Figure 6 presents some of the data presented by Scrivener et al. [5]. This data gives the distribution of unhydrated cement in concrete at various ages for a sample of concrete with a w/c ratio of 0.4. Due to the wall effect upon mixing of the concrete, there are less cement grains in the fresh state near the surface of an aggregate or fiber than further away in the cement paste region. Thus, the water-to-cement ratio in the ITZ region is higher than in the cement paste. This is shown in Figure 6. At mixing (calculated), the volume fraction of unhydrated cement increases rapidly from 0 to 31 percent by volume as the distance from the surface of the aggregate increases from 0 to 3 µm. The high water-to-cement ratio of the ITZ indicates that this region is weaker than the cement paste. As the distance from the surface of the aggregate increases, the volume fraction of unhydrated cement increases. Thus, the ITZ is a region of transition. At a distance of 20 µm from the surface of the aggregate, the change in the volume fraction of unhydrated cement for mixing, 1 day, 28 days, and 1 year are: 45, 21, 13, and 4.5 percent per µm, respectively. For the data corresponding to mixing and 1 year, these values occurred earlier at approximately 11 µm from the surface of the aggregate. Figure 5. Aggregate on left, white lines are at distances of 20 and 50 µm from interface [5] From Figure 6, the initial change (increase) in volume fraction of unhydrated cement per µm from the surface of the aggregate can be calculated. These rates correspond to: 4.75, 1.33, 0.67, and 0.27 (change in percent per µm) for mixing, 1 day, 28 day, and 1 year, respectively. Clearly, there is a significant change in the rate from mixing and 1 day. A significant amount of hydration begins upon mixing where larger crystals develop. Upon hydration, the cement particles are porous in structure with a size distribution that ranges from the nanometres to millimetres. These pores are the weak areas providing pathways for chemical attacks which result in cracking and deterioration [7]. These weak areas affect the performance of the cement paste as well as the ITZ regions. High
6 performance fibers such as CNFs may be able to fill these voids and make these regions more structured. The CNFs have ideal mechanical and fracture properties which will benefit the resulting cementitious material. Figure 6. Distribution of unhydrated cement in concrete at various ages (w/c = 0.4) [5] 3. Discussions The ITZ directly affects the properties of concrete, since the ITZ acts as the "weak link in the chain when compared to the cement paste or the aggregate or the fibers. Thus, as the strength and stiffness of the ITZ regions decrease, the strength and stiffness of the resulting concrete also decrease. The total volume of the ITZ regions increases as the total amount of aggregate increases and as the average size of the aggregate increases. Decreasing the volume of the ITZ regions is important for enhancing the structural properties of concrete. This is clearly evident in Figure 5 where areas of voids are visible in the ITZ region. If the ITZ regions could be tailored to have the same properties as the cement paste or very close, this would be ideal. Using very fine aggregates and CNFs that are closer in size to the cement particles offers a good approach to decreasing the total volume of the ITZ regions, and this would increase the mechanical performance of the resulting concrete material. However, CNFs are expensive, but prices are coming down. 4. Conclusions This paper examined the ITZ regions in concrete with CNFs. ITZ is a region of transition from a lower w/c ratio to a value found in the cement paste. The size of the ITZ region ranges from about 15 to 20 µm in thickness. Based on data provided by Scrivener et al. (2004), the initial rate of increase in percent of unhydrated cement per µm from the surface of the aggregate for standard concrete was calculated to be 4.75, 1.33, 0.67, and 0.27 for mixing, 1 day, 28 days, and 1 day, respectively. At mixing, the water-to-cement ratio at the surface of the aggregate was very high.
7 The ITZ regions act as the weak link so making these regions stronger will enhance the overall performance of the material. One way is to use CNFs. These fibers have superior mechanical properties; however, fiber dispersion and bonding are still challenging. Another issue with the CNFs is cost. References 1.S H Kosmatka, B Kerkhoff, and W C Panarese, Design and Control of Concrete Mixtures, Portland Cement Association, 14 th edition, Skokie, Illinois, S P Shah, W J Weiss, and W Yang, Shrinkage Cracking Can it be prevented?, Concrete International, American Concrete Institute, Farmington Hills, Michigan, pp 51-55, April S M Palmquist, Ductile Concrete using Structural Fibers, Proceeding, Precast Concrete Institute (PCI), 54 th Annual Convention and Exhibition, A Keyvani, Huge Opportunities for industry of Nanofibrous Concrete Technology, International Journal of Nanoscience and Nanotechnology, Vol. 3, No. 1, pp 3-11, December K L Scrivener, A K Crumbie, and P Laugesen, The Interfacial Transition Zone (ITZ) Between Cement Paste and Aggregate in Concrete, Interface Science, pp , J F Young, S Mindess, R J Gray, and A Bentur, The Science and Technology of Civil Engineering Materials, Prentice-Hall, pp 186, A Keyvani, S Noboru, and et. al, Effect of Galvanized Steel Fibers on Corrosion Protection of Reinforced Concrete, J. of the The Japan Soc. of Civil Engineers (JSCE), pp 35-46, August 2000.
Investigations of fracture process in concrete using X-ray micro-ct
Investigations of fracture process in concrete using X-ray micro-ct Ł. Skarżyński 1, J. Tejchman 1 1 Gdansk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland, Aims The main objective of
More informationFiber Reinforced Concrete (FRC)
Progress in Fiber Reinforced Concrete (FRC) Concrete is relatively brittle, and its tensile strength is typically only about one tenths of its compressive strength. Regular concrete is therefore normally
More informationTensile Bond Between Substrate Concrete and Normal Repairing Mortar under Freeze Thaw Cycles
4 th International Conference on the Durability of Concrete Structures 24 26 July 2014 Purdue University, West Lafayette, IN, USA Abstract Tensile Bond Between Substrate Concrete and Normal Repairing Mortar
More informationPhysical Properties of Steel Fiber Reinforced Cement Composites Made with Fly Ash
Physical Properties of Steel Fiber Reinforced Cement Composites Made with Fly Ash Assistant Professor, Civil Engineering Department, College of Technological Studies (PAAET), P.O. Box: 34 Ardia, 13136
More informationMicrosilica in Concrete
Microsilica in Concrete Henan Superior Abrasives I/E Co., Ltd Microsilica is a byproduct from silicon metal or ferrosilicon industries, where these metals are produced in submerged electric arc furnaces.
More informationEXTRUSION OF ENGINEERED CEMENT-BASED COMPOSITE MATERIAL
EXTRUSION OF ENGINEERED CEMENT-BASED COMPOSITE MATERIAL Don de Koker and GPAG van Zijl Department of Civil Engineering, University of Stellenbosch, Republic of South Africa Abstract Discontinuous fiber
More informationCharacteristics of KURALON TM (PVA fiber)
Characteristics of KURALON TM (PVA fiber) 1. Chemical Structure CH 2 CH CH 2 CH m n OH OCOCH 3 2. Characteristics High tenacity, High modulus, Low elongation, Light weight, Good resistance against chemicals
More informationPlastic Shrinkage Cracking in Steel and Polypropylene Fiber Reinforced Concrete
Plastic Shrinkage Cracking in Steel and Polypropylene Fiber Reinforced Concrete Abstract Aminath Ali and Prasert Suwanvitaya Department of Civil Engineering, Faculty of Engineering, Kasetsart University
More informationFlexural Performance of Reinforced Concrete Beams with a Layer of Expansive Strain-hardening Cement -based Composite(SHCC)
Flexural Performance of Reinforced Concrete Beams with a Layer of Expansive Strain-hardening Cement -based Composite(SHCC) Hae Jun Yang, June Su Kim, Sung Ho Kim & Hyun Do Yun Chungnam National University,
More informationAn Experimental Investigation on Mechanical Behavior of Macro Synthetic Fiber Reinforced Concrete
International Journal of Civil & Environmental Engineering IJCEE-IJENS Vol: 11 No: 03 18 An Experimental Investigation on Mechanical Behavior of Macro Reinforced Concrete M. J. Hasan 1*, M. Afroz 2 and
More informationMICROSTRUCTURE OF LONG TERM MARINE IMMERGED ANTI-WASHOUT CONCRETE
MICROSTRUCTURE OF LONG TERM MARINE IMMERGED ANTI-WASHOUT CONCRETE Shaowei Yang and Hengjing Ba School of Civil Engineering, Harbin Institute of Technology, Harbin, China Abstract In this contribution,
More informationDURABILITY of CONCRETE STRUCTURES. Part- 3 Concrete Cracks
DURABILITY of CONCRETE STRUCTURES Assist. Prof. Dr. Mert Yücel YARDIMCI Part- 3 Concrete Cracks This presentation covers the subjects in CEB Durable Concrete Structures Guideline and has been prepared
More informationCOMPARISION OF NON DESTRUCTIVE TESTS RESULTS FOR FIRE AFFECTED AND UNAFFECTED CONCRETE STRUCTURE
COMPARISION OF NON DESTRUCTIVE TESTS RESULTS FOR FIRE AFFECTED AND UNAFFECTED CONCRETE STRUCTURE M Yaqub*, University of Engineering & Technology, Taxila, Pakistan 30th Conference on OUR WORLD IN CONCRETE
More informationMicro Structure Analysis of Reactive Powder Concrete
International Journal of Engineering Research and Development e-issn: 2278-067X, p-issn: 2278-800X, www.ijerd.com Volume 4, Issue 2 (October 2012), PP. 68-77 Micro Structure Analysis of Reactive Powder
More informationTotal 30. Chapter 7 HARDENED CONCRETE
Total 30 Chapter 7 HARDENED CONCRETE 1 Shrinkage Shrinkage of concrete is caused by the settlement of solids and the loss of free water from the plastic concrete (plastic shrinkage), by the chemical combination
More informationINNOVATIVE HYBRID WEARING SURFACES FOR FRP BRIDGE DECKS
16 TH INTERNATIONAL CONFERENCE ON COMPOSITE MATERIALS INNOVATIVE HYBRID WEARING SURFACES FOR FRP BRIDGE DECKS Riyad S. Aboutaha Syracuse University Keywords: FRP decks, bridge decks, wearing surfaces Abstract
More informationA. HIGH-STRENGTH CONCRETE (HSC)
EFFECTS OF SILICA FUME ON PROPERTIES OF HIGH-STRENGTH CONCRETE Nasratullah Amarkhail Graduate School of Science and Technology, Department of Architecture and Building Engineering Kumamoto University Kumamoto
More informationPRESTRESSED CONCRETE PLATES WITH HIGH STRENGTH FABRIC
PRESTRESSED CONCRETE PLATES WITH HIGH STRENGTH FABRIC H.W. Reinhardt, M. Krueger Constructions Materials Institute, University of Stuttgart, Germany Abstract Tests on fine grain concrete plates with textile
More informationInvestigations on Some Properties of no-fines Concrete
Investigations on Some Properties of no-fines Concrete T ABADJIEVA and P SEPHIRI Department of Civil Engineering University of Botswana Private Bag 1 Gaborone, Botswana Abstract No-fines concrete is a
More informationProperties of Concrete. Properties of Concrete. Properties of Concrete. Properties of Concrete. Properties of Concrete. Properties of Concrete
CIVL 1112 Contrete Introduction from CIVL 1101 1/10 Concrete is an artificial conglomerate stone made essentially of Portland cement, water, and aggregates. While cement in one form or another has been
More informationFIBER ADDITION AND ITS EFFECT ON CONCRETE STRENGTH
FIBER ADDITION AND ITS EFFECT ON CONCRETE STRENGTH Aiswarya Sukumar M.Tech CE, MACE MG university, Kerala Elson John Asso. Professor, MACE MG University, Kerala Abstract Fibers are generally used as resistance
More informationLaboratory Assessment of Drying Shrinkage of Concretes Containing Shrinkage Reducing Agents Compared with a New Low shrinkage Concrete
Laboratory Assessment of Drying Shrinkage of Concretes Containing Shrinkage Reducing Agents Compared with a New Low shrinkage Concrete Bob Bornstein, Tony Song 2, and Valentin Mukhin 3 Manager Technical
More informationRESILIENT INFRASTRUCTURE June 1 4, 2016
RESILIENT INFRASTRUCTURE June 1 4, 2016 MOMENT REDISTRIBUTION OF GFRP-RC CONTINUOUS T-BEAMS S. M. Hasanur Rahman M.Sc. Student, University of Manitoba, Canada Ehab El-Salakawy Professor and CRC in Durability
More informationEffect of Steel Fibers on Plastic Shrinkage Cracking of Normal and High Strength Concretes
Materials Research. 2010; 13(2): 135-141 2010 Effect of Steel Fibers on Plastic Shrinkage Cracking of Normal and High Strength Concretes Özgür Eren a, Khaled Marar b, * a Department of Civil Engineering,
More informationNon-Destructive Evaluation of Concrete using Ultrasonic Pulse Velocity
Research Journal of Applied Sciences, Engineering and Technology 3(6): 499-504, 2011 ISSN: 2040-7467 Maxwell Scientific Organization, 2011 Received: February 10, 2011 Accepted: May 13, 2011 Published:
More informationProperties of Porous Blocks Using Different Sizes of Coarse Aggregate for Pavement
Properties of Porous Blocks Using Different Sizes of Coarse Aggregate for Pavement A. H. Nur Hidayah *,a, Md. Nor Hasanan b and P. J. Ramadhansyah c Faculty of Civil Engineering, Department of Geotechnical
More informationSTRENGTH PROPERTIES OF STEEL FIBER CONCRETE BY PARTIAL REPLACEMENT OF SILICA FUME
STRENGTH PROPERTIES OF STEEL FIBER CONCRETE BY PARTIAL REPLACEMENT OF SILICA FUME 1 NAMANI SAIKRISHNA, 2 SYED MOIZUDDIN 1 M. Tech(Structural Engineering), Department of Civil Engineering, SVS Group of
More informationStudying of Floating Concrete Report Fall
Studying of Floating Concrete Report 2017 Fall Instructor: Dr. Tzuyang Yu Submitted by Jie Hu Haoyu Lin George Xanthopoulos Haoxiang Yu Marven S Pigeot 1 Table of Contents 1. Introduction... 3 2. Approach...
More informationDestructive and Non- Destructive Testing for Concrete in Sudan - A Comparative Study
IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) e-issn: 2278-1684,p-ISSN: 2320-334X, Volume 12, Issue 6 Ver. VI (Nov. - Dec. 2015), PP 44-48 www.iosrjournals.org Destructive and Non- Destructive
More informationOpen Access Experimental Research on The Effect of Silica Fume on Tensile Basic Creep of Early-age Concrete
Send Orders for Reprints to reprints@benthamscience.ae The Open Civil Engineering Journal, 2015, 9, 997-1001 997 Open Access Experimental Research on The Effect of Silica Fume on Tensile Basic Creep of
More informationStructural Requirements of Bituminous Paving Mixtures
A2D04: Committee on Characteristics of Bituminous Paving Mixtures To Meet Structural Requirements Chairman: Reynaldo Roque Structural Requirements of Bituminous Paving Mixtures AMY EPPS, Texas A&M University
More informationEffects of Steel and Polypropylene Fiber Addition on Interface Bond Strength between Normal Concrete Substrate and Self-Compacting Concrete Topping Slamet Widodo Doctoral Student at Department of Civil
More informationJournal of Engineering Sciences, Assiut University, Vol. 34, No. 4, pp , July 2006
Journal of Engineering Sciences, Assiut University, Vol. 34, No. 4, pp. 1061-1085, July 2006 COMPRESSIVE STRENGTH AND DURABILITY OF CEMENT CONCRETE CONTAINING ALKALI WASTES OF OIL AND CELLULOSE PAPER INDUSTRIES
More informationAnalysis of thermal properties of cement paste during setting and hardening
Analysis of thermal properties of cement paste during setting and hardening D. Mikulić 1, B. Milovanović 1, I. Gabrijel 1 1 University of Zagreb, Faculty of Civil Engineering, Department of Materials,
More informationA Study on Mechanical Properties of Sisal Fiber Reinforced Concrete
A Study on Mechanical Properties of Sisal Fiber Reinforced Concrete 1. INTRODUCTION 1.1 GENERAL Durability of a material is defined as the Mr.S.Sabarinathan 1 service life of a material under given environmental
More informationExperimental investigation of the use of CFRP grid for shear strengthening of RC beams
Journal of Asian Concrete Federation Vol. 2, No. 2, Dec. 2016, pp. 117-127 ISSN 2465-7964 / eissn 2465-7972 http://dx.doi.org/10.18702/acf.2016.12.2.2.117 Experimental investigation of the use of CFRP
More informationULTRA-HIGH STRENGTH SHEAR KEY GROUT
ULTRA-HIGH STRENGTH SHEAR KEY GROUT 187 April 30, 2015 SPECIFICATION FOR ULTRA-HIGH STRENGTH SHEAR KEY GROUT SCOPE This specification consists of the proper material selection and production of Ultra-High-
More informationExperimental Investigation on Flexural Performance of Hybrid Fibre Reinforced Concrete
Experimental Investigation on Flexural Performance of Hybrid Reinforced Concrete S. Eswari Associate Professor, Department of Civil Engineering, Pondicherry Engineering College, Pondicherry,India ---------------------------------------------------------------------***---------------------------------------------------------------------
More informationModule 8: Composite Testing Lecture 36: Quality Assessment and Physical Properties. Introduction. The Lecture Contains
Introduction In the previous lecture we have introduced the needs, background and societies for mechanical testing of composites. In this lecture and subsequent lectures we will see principles for the
More informationEffect of Mix Design on Restrained Shrinkage of Concrete
Bulletin of Environment, Pharmacology and Life Sciences Bull. Env. Pharmacol. Life Sci., Vol (8) July : - Academy for Environment and Life Sciences, India Online ISSN 77-88 Journal s URL:http://www.bepls.com
More informationDetection of Concrete Damage Using Ultrasonic Pulse Velocity Method
Indian Society for Non-Destructive Testing Hyderabad Chapter Proc. National Seminar on Non-Destructive Evaluation Dec. 7-9, 2006, Hyderabad Detection of Concrete Damage Using Ultrasonic Pulse Velocity
More informationRESILIENT INFRASTRUCTURE June 1 4, 2016
RESILIENT INFRASTRUCTURE June 1 4, 2016 MECHANICAL & DURABILITY PROPERTIES OF ENGINEERED CEMENTITIOUS COMPOSITES WITH DIFFERENT AGGREGATES Mohamed A. A. Sherir Ryerson University, Canada Khandaker M. A.
More informationNATURAL POLYMER AS WATERPROOFING COMPOUND IN CEMENT CONCRETE
NATURAL POLYMER AS WATERPROOFING COMPOUND IN CEMENT CONCRETE Remya V 1 and Hima Elizabeth Koshy 2 1,2 Assistant Professor, Department Of Civil Engineering, Mount Zion College of Engineering, Pathanamthitta
More informationDAMAGE RESISTANCE OF REINFORCED CONCRETE STRUCTURES THAT UTILIZE HIGH PERFORMANCE HYBRID FIBER REINFORCED (HYFRC) COMPOSITES
DAMAGE RESISTANCE OF REINFORCED CONCRETE STRUCTURES THAT UTILIZE HIGH PERFORMANCE HYBRID FIBER REINFORCED (HYFRC) COMPOSITES Claudia P. Ostertag Civil & Environmental Engineering Department, University
More informationImpact Fatigue Failure Investigation of HVOF Coatings
C. N. David, 1 M. A. Athanasiou, 1 K. G. Anthymidis, 1 and P. K. Gotsis 1 Journal of ASTM International, Vol. 5, No. 6 Paper ID JAI101571 Available online at www.astm.org Impact Fatigue Failure Investigation
More informationShrinkage Development in High Performance Concrete. Ammar Yahia, P.Eng., Ph.D.,
Shrinkage Development in High Performance Concrete Ammar Yahia, P.Eng., Ph.D., Outlines 1. Introduction 2. High-performance concrete 3. Autogenous shrinkage 4. Autogenous shrinkage stress 5. Autogenous
More informationBRIEF REVIEW ON BOTTOM ASH AS A PARTIAL REPLACEMENT OF FINE AGGREGATE IN ADDITION WITH PPF
BRIEF REVIEW ON BOTTOM ASH AS A PARTIAL REPLACEMENT OF FINE AGGREGATE IN ADDITION WITH PPF *Pradeep G, *Madhu Priya M, ** Tamilvanan K, **Vijayasarathy R *P.G.Scholar, Department of Civil Engineering,PRIST
More informationSHEAR BEHAVIOR OF RC BEAMS USING U-SHAPED UFC PERMANENT FORMWORK WITH SHEAR KEYS OR BOLTS
- Technical Paper - SHEAR BEHAVIOR OF BEAMS USING U-SHAPED PERMANENT FORMWORK WITH SHEAR KEYS OR BOLTS Puvanai WIROJJANAPIROM *1, Koji MATSUMOTO *2, Katsuya KONO *3 and Junichiro NIWA *4 ABSTRACT Shear
More informationEffect of mix design on restrained shrinkage of concrete
Effect of mix design on restrained shrinkage of concrete Assist.Prof.,Dr. Yousef.Zandi Civil Engineering Department Islamic Azad University Tabriz Branch -Iran. Email:Zandi_Engineer@yahoo.com Prof.,Dr.
More informationAkhter B. Hossain,P. Abstract
Paper accepted for presentation and publication in the Proceedings of Conference on Fiber Composites, High-Performance Concretes, and Smart Materials organized by International Center for Fiber Reinforced
More informationRECYCLED AGGREGATE CONCRETE EXPOSED TO ELEVATED TEMPERATURE
RECYCLED AGGREGATE CONCRETE EXPOSED TO ELEVATED TEMPERATURE Arundeb Gupta, Saroj Mandal and Somnath Ghosh Department of Civil Engineering, Jadavpur University, India E-mail: arundeb_gupta@yahoo.co.in ABSTRACT
More informationO U T L I N E C O N S T R U C T I O N M A T E R I A L S C O M P O S I T E C O M P O S I T E. Introduction & History
O U T L I N E Introduction & History C O N S T R U C T I O N M A T E R I A L S FIBER-REINFORCED COMPOSITES 2010 Praveen Chompreda, Mahidol University Fiber-Reinforced Polymer (FRP) Fibers and Matrices
More informationEffect of supplementary cementitious materials on the properties of pervious concrete with fixed porosity
Southern Cross University epublications@scu 23rd Australasian Conference on the Mechanics of Structures and Materials 2014 Effect of supplementary cementitious materials on the properties of pervious concrete
More informationNumerical Analysis of Behavior of UHPC Panels under High Velocity Impact Loading
Numerical Analysis of Behavior of UHPC Panels under High Velocity Impact Loading Sanghee Kim 1) and Thomas Kang 2) 1), 2) Department of Architecture and Architectural Engineering, Seoul National University,
More informationCourse Concrete Technology Course Code Theory Term Work POE Total Max. Marks Contact Hours/ week
Course Concrete Technology Course Code 43588 Examination Scheme Theory Term Work POE Total Max. Marks 100 50 -- 150 Contact Hours/ week 3 2 -- 5 Prepared by Mr. C.S. Patil / Mr. S.P. Patil Date Prerequisites
More informationDETERMINATION OF ULTIMATE FLEXTURAL CAPACITY OF STRENGTHENED BEAMS WITH STEEL PLATES AND GFRP INTRODUCTION
13 th World Conference on Earthquake Engineering Vancouver, B.C., Canada August 1-6, 2004 Paper No. 3242 DETERMINATION OF ULTIMATE FLEXTURAL CAPACITY OF STRENGTHENED BEAMS WITH STEEL PLATES AND GFRP Javad
More informationECS. High Strength Concrete. North Harbour Stadium Influences on Concrete Strength Performance. ECS High Strength Concretes
High Concrete North Harbour Stadium 1997 Influences on Concrete Performance ECS High Concretes Enhancing concrete service under demanding service conditions Curing Technical Data Engineered Concrete Solutions
More informationNanoscale Modification of Cementitious Materials
Nanoscale Modification of Cementitious Materials S.P. Shah, M.S. Konsta-Gdoutos, Z.S. Metaxa, and P. Mondal1 Abstract. This research investigates changes in the nanostructure and the nanoscale local mechanical
More informationDeterioration of Asbestos-Cement Pipes
Deterioration of Asbestos-Cement Pipes Thulasi Sathiyaseelan Professor Yinong Liu School of Mechanical Engineering Esther Loh CEED Client: Water Corporation Abstract Asbestos cement (AC) pipes make up
More informationCRACKING IN FIBRE CEMENT PRODUCTS
Page 59 CRACKING IN FIBRE CEMENT PRODUCTS S.A.S. AKERS AC CONSULTING, VORDERDORFSTRASSE 31, 8753 MOLLIS, SWITZERLAND ABSTRACT This paper provides the reader with a general insight into the problem of cracking
More informationDetection of Thermal Cracks in Early-Age Concrete by AE
www.crl.issres.net Vol. 2 (3) Sep. 211 Detection of Thermal Cracks in Early-Age Concrete by AE T. Watanabe 1c, T. Ohno 2, and C. Hashimoto 1 1 Department of Civil and Environmental Engineering The University
More informationEFFECT OF CURING METHODS ON THE COMPRESSIVE STRENGTH OF CONCRETE
EFFECT OF CURING METHODS ON THE COMPRESSIVE STRENGTH OF CONCRETE T. James, A. Malachi, E.W. Gadzama, V. Anametemfiok a Department of Civil Engineering, Federal University of Technology Yola, Nigeria. a
More informationAcid Attack on PCCP Mortar Coating. Dipayan Jana, P.G. 1 Richard A. Lewis, P. E. 2
Acid Attack on PCCP Mortar Coating Dipayan Jana, P.G. 1 Richard A. Lewis, P. E. 2 Abstract During the failure investigation of a 2.59 meter (102 inch) diameter prestressed concrete cylinder pipe (PCCP)
More informationStudies on ductility of RC beams in flexure and size effect
Studies on ductility of RC beams in flexure and size effect G. Appa Rao* & I. Vijayanand *University of Stuttgart, 7569, Stuttgart, Germany Indian Institute of Technology Madras, Chennai-6 36, India R.
More informationEffect of Particle Size on Properties of Wood-Flour Reinforced Polypropylene Composites
The Fourth International Conference on Woodfiber-Plastic Composites Effect of Particle Size on Properties of Wood-Flour Reinforced Polypropylene Composites Nicole M. Stark Mark J. Berger Abstract Research
More informationSilica Fume An Admixture for High Quality Concrete
Silica Fume An Admixture for High Quality Concrete Vikas Srivastava 1, V. C. Agarwal 2, Atul 3, Rakesh Kumar 4, P. K. Mehta 4 1. Assistant Professor, Civil Engg. Department, SHIATS (Formerly AAI-DU), Allahabad.
More informationPatching repair with ECC on cracked concrete surface
Patching repair with ECC on cracked concrete surface K. Rokugo 1, M. Kunieda 2 and S. C. Lim 3 1 Gifu University, Japan 2 Nagoya University, Japan 3 Deros Co.,Ltd, Japan Abstract Performance requirements
More informationInvestigation of Nanosilica in Enhancing the Strength of Cement Concrete
Investigation of Nanosilica in Enhancing the Strength of Cement Concrete F.Mohamed Yasir Arafath 1, S.Ajeeth Peter Francisco 2, S.Vinoth Bharathi 3, M.Kirubakaran 4, N.Elakkiyarajan 5 U.G Student, Department
More informationEVOLUTION OF HIGH STRENGTH CONCRETE OF M80 GRADE
EVOLUTION OF HIGH STRENGTH CONCRETE OF M80 GRADE D.VASAVI SWETHA Assistant Professor, Civil Department, Dadi Institute of Engineering and Technology. ABSTACT The primary difference between high-strength
More informationFundamentals of Concrete
Components Cement Water Fine Aggregate Coarse Aggregate Fundamentals of Range in Proportions Advantages of Reducing Water Content: Increased strength Lower permeability Fundamentals of Increased resistance
More informationSupplementary Cementitious Materials (SCMs) Cement Hydration: 3/29/2017. SCMs effect on hydration. Hydration Schematic
Supplementary Cementitious Materials (SCMs) Ohio Precast Concrete Association March 2017 Meeting Jay Whitt Lehigh Cement Technical Services Engineer Supplementary Cementitious Materials (SCMs) Cement Hydration:
More informationReplacing Fibre Reinforced Concrete with Bitumen Asphalt in Airports
Replacing Fibre Reinforced Concrete with Bitumen Asphalt in Airports Y.Mohammadi, H. M. Ghasemzadeh, T.B. Talari, M.A. Ghorbani Abstract Concrete pavement has superior durability and longer structural
More informationTHE DEVELOPMENT OF MICROSTRUCTURE OF PORTLAND CEMENT MORTARS FROM THE FRESH TO THE HARDENED STATE
THE DEVELOPMENT OF MICROSTRUCTURE OF PORTLAND CEMENT MORTARS FROM THE FRESH TO THE HARDENED STATE Knut O. Kjellsen*, Norcem AS, Heidelberg Cement Group, Norway, The Norwegian University of Science and
More informationOptimizing concrete mixtures with minimum cement content for performance and sustainability
Graduate Theses and Dissertations Graduate College 2010 Optimizing concrete mixtures with minimum cement content for performance and sustainability Ezgi Yurdakul Iowa State University Follow this and additional
More informationEFFECT OF SILICA FUME ON VARIOUS PROPERTIES OF FIBRE REINFORCED CONCRETE
International Journal of Civil Engineering and Technology (IJCIET) Volume, Issue 4, July-August 216, pp. 42 48 Article ID: IJCIET 4_1 Available online at http://www.iaeme.com/ijciet/issues.asp?jtype=ijciet&vtype=&itype=4
More informationSELF-CONSOLIDATING CONCRETE FOR SLIP-FORM CONSTRUCTION: PROPERTIES AND TEST METHODS
SELF-CONSOLIDATING CONCRETE FOR SLIP-FORM CONSTRUCTION: PROPERTIES AND TEST METHODS Kejin Wang (1), Surendra P. Shah (2) and Thomas Voigt (3) (1) Department of Civil, Construction and Environmental Engineering,
More informationEFFECT OF NANO SILICA ON THE COMPRESSIVE STRENGTH OF CONCRETE
EFFECT OF NANO SILICA ON THE COMPRESSIVE STRENGTH OF CONCRETE 1 BILLA MAHENDER, 2 B. ASHOK 1 M. Tech (Structural Engineering), Department of Civil Engineering, SUJALA BHARATI INSTITUTE OF TECHNOLOGY, Ogulapur,
More informationIntroduction to Joining Processes
4. TEST METHODS Joints are generally designed to support a load, and must be tested to evaluate their load-supporting capabilities. However, it is also important to evaluate, not the joint, but rather
More informationDevelopment of High Early-Strength Concrete for Accelerated Bridge Construction Closure Pour Connections
University of Massachusetts Amherst ScholarWorks@UMass Amherst Masters Theses Dissertations and Theses 2017 Development of High Early-Strength Concrete for Accelerated Bridge Construction Closure Pour
More informationEffect of Zinc Oxide Nanoparticle on Strength of Cement Mortar
IJSTE - International Journal of Science Technology & Engineering Volume 3 Issue 05 November 2016 ISSN (online): 2349-784X Effect of Zinc Oxide Nanoparticle on Strength of Cement Mortar D. Nivethitha S.
More informationFailure mechanisms of concrete under impact loading
Failure mechanisms of concrete under impact loading I. Vegt & K. van Breugel Delft University of Technology, Delft, The Netherlands J. Weerheijm TNO Defence, Security and Safety, Rijswijk, The Netherlands
More informationESTIMATION OF THE POROSITY OF PORTLAND CEMENT PASTES USING BACKSCATTERED ELECTRON IMAGE
Courrier du Savoir N 04, Juin 03, pp. 4-51 ESTIMATION OF THE POROSITY OF PORTLAND CEMENT PASTES USING BACKSCATTERED ELECTRON IMAGE MELLAS M.*, MEZGHICHE B.* & ASH J. E.** *Laboratoire de génie civil, Université
More informationStrength of Normal Concrete Using Metallic and Synthetic Fibers Vikrant S. Vairagade* a and Kavita S. Kene b
Available online at www.sciencedirect.com Procedia Engineering 51 ( 2013 ) 132 140 Chemical, Civil and Mechanical Engineering Tracks of 3 rd Nirma University International Conference Strength of Normal
More informationULTRA HIGH PERFORMANCE AND HIGH EARLY STRENGTH CONCRETE
ULTRA HIGH PERFORMANCE AND HIGH EARLY STRENGTH CONCRETE Mehdi Sadeghi e Habashi, Seraj Higher Education Institue, Iran 36th Conference on OUR WORLD IN CONCRETE & STRUCTURES: 14-16 August 2011, Singapore
More informationProperties of polypropylene fiber reinforced silica fume expansive-cement concrete
Construction and Building Materials 13 1999 171 177 Properties of polypropylene fiber reinforced silica fume expansive-cement concrete Houssam A. Toutanji Department of Ci il and En ironmental Engineering,
More informationFabrication of Functionally Graded-cellular Structures of Cement-based Materials by Coextrusion
Fabrication of Functionally Graded-cellular Structures of Cement-based Materials by Coextrusion Y. Chen, L. J. Struble, G. H. Paulino Department of Civil and Environmental Engineering University of Illinois
More informationCONSIDERATIONS ON THE THRESHOLD CHLORIDE CONTENT VALUES ON THE CORROSION OF STEEL BARS IN CONCRETE
CONSIDERATIONS ON THE THRESHOLD CHLORIDE CONTENT VALUES ON THE CORROSION OF STEEL BARS IN CONCRETE N.Otsuki*, Tokyo Institute of Technology, Japan T. Nishida, Tokyo Institute of Technology, Japan M. Madlangbayan,
More informationChapter VI Mix Design of Concrete
CIV415 CONCRETE TECHNOLOGY Chapter VI Mix Design of Concrete Assist.Prof.Dr. Mert Yücel YARDIMCI Advanced Concrete Technology - Zongjun Li 1 Mix Design Mix design can be defined as the processes of selecting
More informationSTUDY ON SILICA FUME REPLACED CONCRETE WITH SUPER PLASTICIZER
Int. J. Chem. Sci.: 14(S1), 2016, 359-366 ISSN 0972-768X www.sadgurupublications.com STUDY ON SILICA FUME REPLACED CONCRETE WITH SUPER PLASTICIZER R. M. MADHANASREE *,a, A. JOE PAULSON b and R. ANGELINE
More informationWater Penetration into Micro-cracks in Reinforced Concrete
Restoration of Buildings and Monuments Vol. 20, No. 2, 85 94 (2014) DOI 10.12900/RBM14.20.2-0008 Water Penetration into Micro-cracks in Reinforced Concrete P. Zhang 1,2, F. H. Wittmann 1,3*, M. Haist 2,
More informationPHYSICAL, MECHANICAL, AND DURABILITY CHARACTERIZATION OF CARBON FRP CABLE
PHYSICAL, MECHANICAL, AND DURABILITY CHARACTERIZATION OF CARBON FRP CABLE Ahmed H. Ali 1, Hamdy M. Mohamed 2, Patrice Cousin 3, Adel ElSafty 4, and Brahim Benmokrane 5 1 Doctoral candidate, University
More informationCORROSION MONITORING IN REINFORCED CONCRETE BY ACOUSTIC EMISSION
Abstract CORROSION MONITORING IN REINFORCED CONCRETE BY ACOUSTIC EMISSION MASAYASU OHTSU and YUICHI TOMODA Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, JAPAN Cracking of concrete due to corrosion
More informationSHEAR PERFORMANCE OF RC MEMBERS STRENGTHENED WITH EXTERNALLY BONDED FRP WRAPS
Proc., 12th World Conference on Earthquake Engineering, Jan 3- Feb 4, 2, Auckland, New Zealand, paper 35,1 pp SHEAR PERFORMANCE OF RC MEMBERS STRENGTHENED WITH EXTERNALLY BONDED FRP WRAPS AHMED KHALIFA,
More informationCHAPTER 7: SERVICEABILITY LIMIT STATES
CHAPTER 7: SERVICEABILITY LIMIT STATES 7.1 GENERAL It shall be in accordance with JSCE Standard Specification (Design), 7.1. 7.2 CALCULATION OF STRESS AND STRAIN It shall be in accordance with JSCE Standard
More informationReinforcing efficiency of glass fibres in low volume class F fly ash concrete
Vol. 4(6), pp. 184-191, June, 2013 DOI 10.5897/JCECT2013.0265 ISSN 1996-0816 2013 Academic Journals http://www.academicjournals.org/jcect Journal of Civil Engineering and Construction Technology Full Length
More informationCarbon-fiber Reinforced Concrete with Short Aramid-fiber Interfacial Toughening
2016 International Conference on Electronic Information Technology and Intellectualization (ICEITI 2016) ISBN: 978-1-60595-364-9 Carbon-fiber Reinforced Concrete with Short Aramid-fiber Interfacial Toughening
More informationPractical Experiences on Cracking of Concrete Slabs on Ground
11 Practical Experiences on Cracking of Concrete Slabs on Ground Jukka Lahdensivu Lic. Tech., Senior Research Scientist Tampere University of Technology Tekniikankatu 12, P.O. Box 600, FI-33101 Tampere
More informationFiber Reinforced Concrete Pavement & Shrinkage
International Academic Institute for Science and Technology International Academic Journal of Science and Engineering Vol. 3, No. 5, 2016, pp. 98-106. ISSN 2454-3896 International Academic Journal of Science
More informationPHYSICAL AND CHEMICAL PROPERTIES OF POLYMER IMPREGNATED CONCRETE ON THE PREPARATION CONDITIONS
PHYSICAL AND CHEMICAL PROPERTIES OF POLYMER IMPREGNATED CONCRETE ON THE PREPARATION CONDITIONS * ** Won Mook Lee, J Priya Nair, Chul Woo Lee, Du Hyun Ku, Jeong Soon Park, Hun Young Park Department of Chemical
More informationMicro Filler Effects of Silica-Fume on the Setting and Hardened Properties of Concrete
Research Journal of Applied Sciences, Engineering and Technology 6(14): 2649-2654, 2013 ISSN: 2040-7459; e-issn: 2040-7467 Maxwell Scientific Organization, 2013 Submitted: January 19, 2013 Accepted: February
More information