Download or read book Reduced Cementitious Material in Optimized Concrete Mixtures written by Peter Taylor and published by . This book was released on 2021 with total page 163 pages. Available in PDF, EPUB and Kindle. Book excerpt: This document reports the activities and observations of a research team that performed on-site and laboratory testing of concrete mixtures with reduced cementitious materials content placed in two cells at the MnROAD facility in Albertville, Minnesota. The overall objectives of this research project included investigating the early age characteristics of concrete paving mixes containing reduced cementitious contents as well as their long-term performance. It was observed that while workability was marginal in the mixture proportioned with 470 lb/yd3, all other properties of the test sections were similar to those of the control section.
Download or read book Guidelines for Concrete Mixtures Containing Supplementary Cementitious Materials to Enhance Durability of Bridge Decks written by John S. Lawler and published by Transportation Research Board. This book was released on 2007 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt: NCHRP Report 566 is designed to help facilitate the use of supplementary cementitious materials to enhance durability of concrete used in highway construction, especially bridge decks. The report includes a methodology for selecting optimum concrete mixture proportions that focuses on durability aspects of concrete and the performance requirements for specific environmental conditions. The methodology is presented in a text format and as a computational tool, in the form of a Visual Basic?driven Microsoft Excel spreadsheet. Background information and a hypothetical case study was published as NCHRP Web-Only Document 110: Supplementary Cementitious Materials to Enhance Durability of Concrete Bridge Decks. The Statistical Experimental Design for Optimizing Concrete (SEDOC), the computational tool for the concrete mixture optimization methodology, and the user?s guide are available in a ZIP format for download.
Download or read book Reduction of Minimum Required Weight of Cementitious Materials in WisDOT Concrete Mixes written by and published by . This book was released on 2011 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: This project was designed to explore the feasibility of lowering the cementitious materials content (CMC) used in Wisconsin concrete pavement construction. The cementitious materials studied included portland cement, fly ash, and ground granulated blast furnace slag. For the first phase, mixtures were prepared using the current WisDOT aggregate grading specification. For the second phase, mixtures were prepared using an optimized (e.g. Shilstone) gradation. A variety of tests for fresh and hardened concrete were conducted to determine the viability of low CMC mixtures for use in concrete pavement.
Download or read book Optimization Of Cementitious Material Content For Sustainable Concrete Mixtures Through Value Engineering Approach written by Adel Baghdady and published by . This book was released on 2019 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper studies the effectiveness of applying value engineering to actual concrete mixtures. The study was conducted in the State of Qatar on a number of strategic construction projects with international engineering specifications for the 2022 World Cup projects. The study examined the concrete mixtures of Doha Metro project and the development of KAHRAMAA's (Qatar Electricity and Water Company) Abu Funtas Strategic Desalination Plant, in order to generally improve the quality and productivity of ready-mixed concrete used in construction and hydraulic projects. The application of value engineering to such concrete mixtures resulted in the following: • Improving the quality of concrete mixtures and increasing the durability of buildings in which they are used; • Reducing the waste of excess materials of concrete mixture, optimizing the use of resources, and enhancing sustainability; • Reducing the use of cement, thus reducing CO2 emissions which ensures the protection of environment and public health; • Reducing actual costs of concrete mixtures and, in turn, reducing the costs of construction projects; and • Increasing the market share and competitiveness of concrete producers. This research shows that applying the methodology of value engineering to ready-mixed concrete is an effective way to save around 5% of the total cost of concrete mixtures supplied to construction and hydraulic projects, improve the quality according to the technical requirements and as per the standards and specifications for ready-mixed concrete, improve the environmental impact, and promote sustainability.
Download or read book Optimization of Mixture Proportions for Concrete Pavements Influence of Supplementary Cementitious Materials Paste Content and Aggregate Gradation written by Adam Rudy and published by Purdue University Press. This book was released on 2012-12-31 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ultimate goals of this study included investigation of the optimal ranges for paste content, amount of cementations materials and aggregate gradation for concrete paving mixtures. In general, the optimum concrete mixtures developed in this study contained low paste content (below 23%), and were characterized by low scaling and sorptivity. In addition, it was also possible to achieve high cement replacement levels for these mixtures. Finally, for optimized fly ash mixtures, the selection of well graded aggregate gradation with high packing density increased the most desired paste content for those mixtures, thus indicating that combined aggregate gradation has strong influence on concrete performance. Lastly, concrete mixtures developed with optimum ranges of variables studied in this research contained low cement content. The overall scope of the research was divided into three distinctive phases, each of which is described briefly below: PHASE I: This phase consisted of statistical optimization of the proportions of concrete binder. The Central Composite Design methodology (CCD) was used to design the experiment for the optimization of binder in three types of concrete mixtures: a) cement + fly ash, b) cement + GGBFS, and c) cement + fly ash + GGBFS. The variables studied in each of these systems included: paste content (from 21 to 25 % by mixture volume) and total content of supplementary cementitious material (SCM) in the mixture. This was expressed as weight percent of total binder, and varied depending on the binder system used. PHASE II: The main goal of this phase was to investigate the effect of different aggregate gradations on the fresh and hardened properties of optimized concrete mixtures developed in PHASE I, as well as to identify the most desired aggregate gradations for paving mixtures. Different aggregate gradations were prepared by blending of 2, 3 or 4 different sizes of aggregates based on concept of Shilstone's Coarseness Factor Chart. PHASE III: The concept of air-free paste-aggregate void saturation ratio (k") introduced in PHASE II seemed to fairly accurate link the properties of concrete mixtures with their paste content. Thus, it was decided to further investigate this concept in connection with aggregate packing density ( ). In addition, it was believed that defining optimum values of "k" will allow for revising the paste content ranges developed in PHASE I for different systems, and thus define more general optimum paste ranges for paving mixtures.
Download or read book Optimization of Concrete Mixtures for Use in Structural Elements written by Waleed Faleh Almutairi and published by . This book was released on 2017 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: Portland cement is an essential ingredient in concrete. The use of cement is to enhance the strength as well as other hardened properties of concrete mixtures. Determining the accurate amount of cement is important because the required strength may not be achieved if not enough cement is used. By contrast, when using too much cement, concrete cracking may occur that leads to reducing durability. Researchers at the University of Arkansas (UA) have shown that many bridge decks achieve their 28 day design strength of 4000 psi by 7 days of age. Bridge decks having high strength may experience cracking, which affects the durability. The Arkansas State Highway and Transportation Department (AHTD) classifies two types of concrete mixtures that can be used in bridges. The first is Class S concrete, and the second is Class S(AE). Class S is used for the structural components and does not contain air entrainment while Class S (AE) is mainly used for bridge decks and contains air entrainment. AHTD requires the same minimum cementitious material content for both classes of concrete. The purpose of this research is to determine if the cementitious material content of Class S mixtures can be reduced while still meeting AHTD specifications. The research program examined cementitious material content, Class C fly ash content, and water to cementitious material ratio (w/cm) . For all mixtures, selected fresh and hardened concrete properties were measured to ensure that they complied with AHTD requirements.
Download or read book Cement Replacement Materials written by Ali Akbar Ramezanianpour and published by Springer Science & Business Media. This book was released on 2013-09-24 with total page 345 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this book is to present the latest findings in the properties and application of Supplementary Cementing Materials and blended cements currently used in the world in concrete. Sustainability is an important issue all over the world. Carbon dioxide emission has been a serious problem in the world due to the greenhouse effect. Today many countries agreed to reduce the emission of CO2. Many phases of cement and concrete technology can affect sustainability. Cement and concrete industry is responsible for the production of 7% carbon dioxide of the total world CO2 emission. The use of supplementary cementing materials (SCM), design of concrete mixtures with optimum content of cement and enhancement of concrete durability are the main issues towards sustainability in concrete industry.
Download or read book Practical Concrete Mix Design written by Avijit Chaubey and published by CRC Press. This book was released on 2020-03-17 with total page 185 pages. Available in PDF, EPUB and Kindle. Book excerpt: Practical Concrete Mix Design has been compiled to help readers understand the concrete mix design methodology, including formulas and tables involved in the pertinent steps. This book helps engineers understand the mix design procedure, through illuminating every possible explanation for each step of mix design, limitations given by standards, and practical guides on tailor-making concrete to meet specific requirements. The construction industry needs engineers/experts who can reduce the costs of concrete, and thereby increase their profitability. This book shows effective methods for optimizing concrete and simultaneously achieving the desired properties of concrete. It covers why, how, and when with respect to concrete proportioning and optimization. It further provides the necessary skills for engineers to hone their skills in doing so, understanding the risks involved, and troubleshooting related problems.
Download or read book Using Theoretical and Experimental Particle Packing for Aggregate Gradation Optimization to Reduce Cement Content in Pavement Concrete Mixtures written by Miras Mamirov and published by . This book was released on 2019 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main objective of this study was to evaluate the effect of aggregate particle packing optimization and cement reduction on Nebraska slip-form pavement concrete performance. A literature review was conducted to examine different aggregate optimization tools, quality control tests, and historical data of Nebraska Department of Transportation (NDOT) mixtures. It was found that the Modified Toufar Model has good potential in optimizing particle packing and predicting packing degrees. The combined void content test was found to be useful to experimentally justify optimized aggregate gradations. Two specific pavement concrete workability tests, i.e., the Box Test and the VKelly Test, were used to evaluate the effect of cement reduction and optimized aggregate gradation on pavement concrete workability. The Box Test ranking was modified to provide a more detailed and objective evaluation. Analysis of different aggregate combinations has shown that experimental packing from the combined void content test has a high correlation with estimated packing from the Modified Toufar Model. Results showed that when the optimized aggregate gradation is used, cement content can be effectively reduced by up to 1.0 sack (94 lb/yd3) without compromising the fresh properties, mechanical properties, and permeability. Based on the results of free and restrained shrinkage, it was justified that shrinkage and cracking potential can be reduced in optimized concrete mixtures. Freeze/thaw resistance can be slightly improved with optimized mixtures. A mix design improvement procedure considering both theoretical and experimental packing and the minimum excess paste-to-aggregate ratio can be used to design concrete with an optimum cement content.The main objective of this study was to evaluate the effect of aggregate particle packing optimization and cement reduction on Nebraska slip-form pavement concrete performance. A literature review was conducted to examine different aggregate optimization tools, quality control tests, and historical data of Nebraska Department of Transportation (NDOT) mixtures. It was found that the Modified Toufar Model has good potential in optimizing particle packing and predicting packing degrees. The combined void content test was found to be useful to experimentally justify optimized aggregate gradations. Two specific pavement concrete workability tests, i.e., the Box Test and the VKelly Test, were used to evaluate the effect of cement reduction and optimized aggregate gradation on pavement concrete workability. The Box Test ranking was modified to provide a more detailed and objective evaluation. Considering one of the goals of the study was to maximize the use of local materials, locally available cementitious materials and aggregates from East and West Nebraska were selected. Analysis of different aggregate combinations has shown that experimental packing from the combined void content test has a high correlation with estimated packing from the Modified Toufar Model. Results also demonstrated that the current aggregate combination is not the optimum gradation and can be improved. The experimental program included in this study consisted of three Phases. Phase 1 focused on obtaining promising aggregate blends by maintaining the standard cement content (564 lb/yd3, 335 kg/m3). Fresh concrete properties were the main criteria to select promising blends. Phase 2 included an evaluation of performance of pavement concrete with cement content reduced by 0.5 sack (47 lb/yd3, 28 kg/m3) steps for other reference and optimized aggregate blends. Results justified that when optimum gradation is used, cement could be reduced up to 94 lb/yd3 (56 kg/m3). Phase 3 is the performance evaluation phase, which included evaluating the reference mix and selected promising mixes for setting time, modulus of elasticity, free shrinkage, restrained shrinkage, and freeze/thaw resistance. Mixtures with reduced cement and optimized aggregate gradation have shown improved freeze/thaw resistance and lower shrinkage rate. Finally, a mix design improvement procedure incorporating theoretical and experimental particle packing and using excess paste-to-aggregates ratio as the control parameter was proposed. To sum up, the study has justified that the Modified Toufar Model and the combined void content test can be useful tools in aggregate gradation optimization. In order to evaluate workability of pavement concrete more accurately, the Box Test ranking was modified based on image analysis of surface and edge quality. It was also proved that mixtures with reduced cement content and optimized aggregate gradation perform better in terms of freeze/thaw resistance and shrinkage.
Download or read book Cement Industry written by Hosam Saleh and published by BoD – Books on Demand. This book was released on 2021-06-09 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cement is the basis of the building and construction industry and of fundamental importance for many civil engineering applications. As such, the cement industry is one of the key industries worldwide necessary for the current and future sustainable development of society. Despite its undisputed importance, the cement industry is one of those industrial branches predominately responsible for high energy consumption and excessive generation of large amounts of carbon dioxide and other contaminants that significantly endanger human health and the environment and contributes to global warming.In this context, nanomaterials, polymeric materials, and natural additives are being used for cement enhancement in various applications. This book examines these novel materials and their optimization, characterization, and sustainable application in the building industry and for stabilizing hazardous waste.
Download or read book Optimizing the Mixture of Cementitious Materials for Additive Manufacturing of Concrete Infrastructure written by Keyur Dhawan and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: 3D Printing Technology is one of the most progressive technologies which is rapidly growing in the world of construction. This technology benefits by fast-tracking the speed of construction and reducing the labor cost, which allows more benefit economically and even providing structures with aesthetical looks, better strength and, durability aimed to be as good as casted concrete structures. To optimize the mix design and produce a workable concrete structure, Fused Deposition Modeling has been used for the printing process. The study is done to produce optimized proportions of concrete mix designs that are suitable for 3D printing of concrete. The addition of silica fume, nano- clay, and fly ash as non- cementitious material and superplasticizers, retarders, accelerators, and viscosity admixtures as chemical dosages are reported to control the flow of the concrete, bonding between the ingredients in the matrix and slowing down the hydration process, respectively which provides the structure with better stability. The 3D printing parameters like time, printability window, pressure variation, and other mechanical properties are studied in this research. FE- analysis can analyze the buildability of a specific shape or structure before printing. So that it can save the cost of materials and help with reducing the formation of 3D printed structure. Keywords: Supplementary Cementitious materials, Chemical Dosage, 3D printing parameters, and FE analysis.
Download or read book Design Production and Placement of Self Consolidating Concrete written by Kamal Henri Khayat and published by Springer Science & Business Media. This book was released on 2010-08-12 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dear Colleagues, We are pleased to organize the Sixth International RILEM Symposium on SCC and the Fourth North-American Conference on the Design and Use of SCC, held on Sept 26-29, 2010 in Montreal, Quebec, Canada. The RILEM series of symposia started in 1999 in Stockholm, followed by Tokyo in 2001, Reykjavik in 2003, Chicago in 2005, and Ghent in 2007 with a steadily increasing number of papers, participants, and interest from across the globe. Due to the growing success of SCC, regional conferences have been organized, such as the North-American Conference on the Design and Use of SCC held in Chicago in 2002, 2005, and 2008; the International Symposium on Design, Performance and Use of SCC held nd in Changsa, China in 2005 and in Beijing, China in 2009; as well as the 2 International Conference on Advances in Concrete Technology in the Middle East: SCC held in Abu Dhabi in 2009. It can be concluded that these regional Conferences and Symposia were highly successful and reached a far more international audience than anticipated. Nearly 100 papers were submitted for these proceedings from which the International Scientific Committee selected 37 contributions covering a wide range of timely and original subjects from around the world. We would like to acknowledge the input of the International Scientific Committee for providing critical input to guarantee high quality of these peer-reviewed proceedings. We invite you to explore a wealth of information in the electronic proceedings.
Download or read book Reducing Cement Content in Concrete Mixtures written by and published by . This book was released on 2011 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt: Concrete mixtures contain crushed rock or gravel, and sand, bound together by Portland cement in combination with supplemental cementitious materials (SCMs), which harden through a chemical reaction with water. Portland cement is the most costly component of concrete mixtures, and its production creates significant amounts of green house gases. To reduce costs and environmental impacts, current WisDOT practice allows a for replacement of a portion of Portland cement supplemental cementitious materials (SCMs) such as coal fly ash or slag cement, both industrial by-products of coal and iron production, respectively. WisDOT has set a maximum limit on Portland cement replacement through use of SCMs to ensure its performance on concrete pavements. Therefore, the only opportunity to reduce the usage of Portland cement is to lower the required cementitious materials content for WisDOT approved mix designs. The potential benefits in terms of economic costs and environmental impacts are significant, however decreasing the cementitious materials content of a mixture too drastically can reduce pavement strength and durability. It can also reduce workability, or the ease with which a mixture can be compacted and placed during construction.
Download or read book High Performance Concretes written by Paul Zia and published by . This book was released on 1991 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: This state-of-the-art report summarizes the results of an extensive search and review of available literature on the mechanical properties of concrete, with particular reference to high performance concrete for highway applications. Included in the review and discussion are the behavior of plastic concrete as well as the strength and deformation characteristics of hardened concrete. Both short-term and long-term effects are considered. Based on the review of the available information, research needs are identified. It is concluded that much research is needed to develop data on the strength and durability properties of concrete which develops high strength, particularly very early strength.
Download or read book A Comprehensive Method for Concrete Mix Design written by Janamian, K. and published by Materials Research Forum LLC. This book was released on 2020-01-20 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: A novel method of concrete mix design is presented. Tests with various constituent materials are reported in great detail. Both laboratory tests and applications in industry show the method to be very successful for all kinds of normal constituent materials, including silica fume, ground granulated blast furnace slag, fly ash, natural pozzolans, blended cement, fine and coarse aggregates, water, air entraining admixtures, plasticizers and super-plasticizers.
Download or read book Nonconventional Concrete Technologies written by Committee on Nonconventional Concrete Technologies for Renewal of the Highway Infrastructure and published by National Academies Press. This book was released on 1997-04-08 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nonconventional Concrete Technologies: Renewal of the Highway Infrastructure identifies research and development opportunities in innovative, nonconventional materials and processes that have the potential to accelerate the construction process, improve the durability of highway pavement and bridges, and enhance the serviceability and longevity of new construction under adverse conditions.
Download or read book Optimization Methods for Material Design of Cement based Composites written by A.M. Brandt and published by CRC Press. This book was released on 1998-06-18 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides a clear, comprehensive introduction to the subject. Different problems of optimization are considered and illustrated with examples. Large sets of new experimental data are presented and discussed.
