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Study Of Early Age Bridge Deck Cracking In Nevada And Wyoming
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Book Synopsis Study of Early-Age Bridge Deck Cracking in Nevada and Wyoming by : Dale P. Bentz
Download or read book Study of Early-Age Bridge Deck Cracking in Nevada and Wyoming written by Dale P. Bentz and published by CreateSpace. This book was released on 2012-01-31 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: In late 2009, the Echo Wash and Valley of Fire bridge decks were constructed in the Lake Mead National Recreation area in Nevada. Within six months after installation, in early 2010, both decks exhibited considerable transverse cracking, with some cracks extending through the thickness of the deck. Similar cracking was observed in the Snake River bridge deck in Wyoming. This report details the results of a two-pronged approach to examining the causes of such cracking.
Book Synopsis Early Age Shrinkage and Cracking of Nevada Concrete Bridge Decks by :
Download or read book Early Age Shrinkage and Cracking of Nevada Concrete Bridge Decks written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Early Age Shrinkage and Cracking of Nevada Concrete Bridge Decks by : Heinere Howard Ah-Sha
Download or read book Early Age Shrinkage and Cracking of Nevada Concrete Bridge Decks written by Heinere Howard Ah-Sha and published by . This book was released on 2001 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Phase I: Minimization of Cracking in New Concrete Bridge Decks by : Nicole Duffala
Download or read book Phase I: Minimization of Cracking in New Concrete Bridge Decks written by Nicole Duffala and published by . This book was released on 2016 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cracking of newly constructed high-performance concrete (HPC) bridges is a problem recognized nationwide and the Nevada Department of Transportation has been plagued with this distress in their HPC concrete bridge decks. This research effort is a strategic attempt to reduce or eliminate random cracking that is caused by restrained shrinkage in new concrete bridge decks constructed in Nevada. The overall objective will be achieved through a three phase research program of which the results of Phase I are being reported in this document. Phase I research findings provide a synthesis of state, regional, and national practices and knowledge on factors contributing to HPC bridge deck cracking. With respect to materials and mixture proportioning, the overwhelming conclusion is that the shrinkage of the concrete mixture, especially at early-ages, must be reduced and the concrete’s resistance to cracking must be Improved. A rigorous, Phase II laboratory experiment was designed and is presented herein. This Phase II laboratory experiment focuses on local materials and will assess the properties of concrete mixtures that are related to early-age drying shrinkage restraint cracking. Ultimately, these research findings could be used to revise standard specifications and special provisions for Nevada DOT bridge decks and eventually reduce the overall incidence of restraint cracking due to concrete drying shrinkage.
Book Synopsis Phase 1 Report on the Development of Predictive Model for Bridge Deck Cracking and Strength Development by :
Download or read book Phase 1 Report on the Development of Predictive Model for Bridge Deck Cracking and Strength Development written by and published by . This book was released on 2009 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: Early-age cracking, typically caused by drying shrinkage (and often coupled with autogenous and thermal shrinkage), can have several detrimental effects on long-term behavior and durability. Cracking can also provide ingress of water that can drive chemical reactions, such as alkali-silica reaction (ASR) and sulfate attack. Because of the problems associated with cracking observed in bridge decks, and the impact of early-age cracking on long-term performance and durability, it is imperative that bridge decks be constructed with minimal early-age cracking and that exhibit satisfactory long-term performance and durability. To achieve these goals for bridges in the state of Texas, a research team has been assembled that possesses significant expertise and background in cement chemistry, concrete materials and durability, structural performance, computational mechanics (finite difference/element), bridge deck construction and maintenance, monitoring of in-site behavior of field structures, and the development of test methods and specifications aimed at practical implementation by state highway departments. This proposal describes a laboratory- and field-based research program aimed at developing a bridge deck cracking model that will ultimately be integrated into ConcreteWorks, a suite of software programs developed for TxDOT by this same research team.
Book Synopsis Mitigation Strategies for Early-age Shrinkage Cracking in Bridge Decks by : Pizhong Qiao (Civil engineer)
Download or read book Mitigation Strategies for Early-age Shrinkage Cracking in Bridge Decks written by Pizhong Qiao (Civil engineer) and published by . This book was released on 2010 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Early-age shrinkage cracking has been observed in many concrete bridge decks in Washington State and elsewhere around the U.S. The cracking increases the effects of freeze-thaw damage, spalling, and corrosion of steel reinforcement, thus resulting in premature deterioration and structural deficiency of the bridges. In this study, the main causes of the early-age cracking in the decks are identified, and concrete mix designs as a strategy to prevent or minimize the shrinkage cracking are evaluated. Different sources (eastern and western Washington) and sizes of aggregates are considered, and the effects of paste content, cementitious materials (cement, fly ash, silica fume, slag), and shrinkage reducing admixture (SRA) are evaluated. A series of fresh, mechanical and shrinkage property tests were performed for each concrete mix. The outcomes of this study identify optimum concrete mix designs as appropriate mitigation strategies to reduce or eliminate early-age shrinkage cracking and thus help minimize shrinkage cracking in the concrete bridge decks, potentially leading to longer service life.
Book Synopsis Cause and Control of Transverse Cracking in Concrete Bridge Decks by : M. Ala Saadeghvaziri
Download or read book Cause and Control of Transverse Cracking in Concrete Bridge Decks written by M. Ala Saadeghvaziri and published by . This book was released on 2002 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many concrete bridge decks develop transverse cracking and most of these cracks develop at early ages, some right after construction and some after the bridge has been opened to traffic for a period of time. Structural design factors have not been the subject of much research in the past and they were the main thrust of this research study. Using 2-D and 3-D linear and nonlinear finite element models many design factors such as girder stiffness, deck thickness, girder spacing, relative stiffness of deck to girder, amount of reinforcements, etc., were studied. The research study also included a comprehensive review of the existing literature as well as survey of 24 bridges in the state of New Jersey. Results of each research task are presented and discussed in detail. Furthermore, based on analytical results and literature review, the effect of various factors are quantified and specific recommendations for possible consideration in design are made.
Book Synopsis Cracking in Concrete Bridge Decks by : Tony R. Schmitt
Download or read book Cracking in Concrete Bridge Decks written by Tony R. Schmitt and published by . This book was released on 1995 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: The causes of cracking in bridge decks are investigated and procedures are recommended to alleviate the problem. Forty continuous steel girder bridges, thirty-seven composite and three noncomposite bridges are evaluated. Field surveys conducted to document cracking patterns and to determine the crack density of each bridge are described. Information collected from construction documents, field books, and weather data logs is presented and compared to the observed levels of cracking to identify correlations between cracking and the variables studied. Thirty-one variables are considered such as material properties, site conditions, construction procedures, design specifications, age of bridge and traffic volume. Based on the research reported herein, cracking in monolithic bridge decks increases with increasing values of concrete slump, percent volume of water and cement, water content, and compressive strength, and decreasing values of air content (especially below 6.0%). Bridge deck overlays placed with zero slump concrete consistently exhibit high levels of cracking. Cracking in overlays also increases as placement lengths increase. High maximum air temperatures and large changes in air temperature on the day of casting aggravate cracking in monolithic bridge decks. High average air temperatures and large changes in air temperature similarly aggravate cracking in bridge deck overlays. Both monolithic and two layer bridges with fixed-ended girders exhibit increased cracking near the abutments compared to those with pin-ended girders.
Book Synopsis Investigate Causes and Develop Methods to Minimize Early-age Deck Cracking on Michigan Bridge Decks by : Haluk Aktan
Download or read book Investigate Causes and Develop Methods to Minimize Early-age Deck Cracking on Michigan Bridge Decks written by Haluk Aktan and published by . This book was released on 2003 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Mitigation Strategies for Early-age Shrinkage Cracking in Bridge Decks by : Pizhong Qiao
Download or read book Mitigation Strategies for Early-age Shrinkage Cracking in Bridge Decks written by Pizhong Qiao and published by . This book was released on 2010 with total page 79 pages. Available in PDF, EPUB and Kindle. Book excerpt: Early-age shrinkage cracking has been observed in many concrete bridge decks in Washington State and elsewhere around the U.S. The cracking increases the effects of freeze-thaw damage, spalling, and corrosion of steel reinforcement, thus resulting in premature deterioration and structural deficiency of the bridges. In this study, the main causes of the early-age cracking in the decks are identified, and concrete mix designs as a strategy to prevent or minimize the shrinkage cracking are evaluated. Different sources (eastern and western Washington) and sizes of aggregates are considered, and the effects of paste content, cementitious materials (cement, fly ash, silica fume, slag), and shrinkage reducing admixture (SRA) are evaluated. A series of fresh, mechanical and shrinkage property tests were performed for each concrete mix. The outcomes of this study identify optimum concrete mix designs as appropriate mitigation strategies to reduce or eliminate early-age shrinkage cracking and thus help minimize shrinkage cracking in the concrete bridge decks, potentially leading to longer service life.
Book Synopsis Assessment of the Cracking Problem in Newly Constructed Bridge Decks in Colorado by : Yunping Xi
Download or read book Assessment of the Cracking Problem in Newly Constructed Bridge Decks in Colorado written by Yunping Xi and published by . This book was released on 2003 with total page 83 pages. Available in PDF, EPUB and Kindle. Book excerpt: Early age cracking on concrete bridge decks has been experienced by many state departments of transportation (DOTs). In Colorado the cracking problem on newly constructed bridge decks has not been completely solved. In this study, the extent and causes of the cracking problem were investigated, and necessary changes to alleviate the cracking problem were identified. To achieve these goals, current Colorado Department of Transportation (CDOT) practice was reviewed and compared with other DOTs practices for construction of bridge decks. A database analysis of field inspection results was performed.
Book Synopsis Study of Internal Strains Developed in Concrete Decks at Early Ages in Steel Continuous Bridges by : Fernando Rafael Benitez Ortiz
Download or read book Study of Internal Strains Developed in Concrete Decks at Early Ages in Steel Continuous Bridges written by Fernando Rafael Benitez Ortiz and published by . This book was released on 2019 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Arkansas Department of Transportation (ARDOT) has identified bridge deck cracking shortly after concrete decks are placed and prior to applying traffic loads. Previous researchers have confirmed improper construction practices and design methods can lead to deck cracking. Currently, many contractors throughout Arkansas are using continuous deck pours. This construction approach may restrict the concrete slab from movement during early age shrinkage, causing tensile stresses to develop. The final stresses at the end of construction must be lower than the concrete tensile strength, if not cracking issues will develop. Eventually, these cracks may enlarge due to service load stresses and environmental damage. A nation-wide Department of Transportation (US DOTs) survey was performed to investigate the early age cracking extensiveness level in other state's bridges and what corrections, if any, they have made to address this problem. Additionally, Arkansas bridges with early age cracking were visited to examine any trends and inform instrumentation for bridge testing. A bridge deck was instrumented with 32 vibrating wire strain gauges prior to concrete placement to investigate strain and temperature changes in the first 14 days. Eurocode and ACI approximations for concrete mechanical properties were compared to field measured data for improving the understanding of an early age concrete deck behavior in a continuous steel bridge. Stress analysis study through the span length of bridge 030428 detected some locations prone to concrete cracking due to the variability of concrete mechanical properties and stress developed in the concrete deck. This thesis describes the results of this monitoring and anything that can be learned about formation of concrete stresses in continuous concrete bridge deck pours.
Book Synopsis Numerically Modeling Steel Continuous Bridges for Early Age Concrete Deck Cracking by : Abdul Aziz Salah
Download or read book Numerically Modeling Steel Continuous Bridges for Early Age Concrete Deck Cracking written by Abdul Aziz Salah and published by . This book was released on 2020 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: Early age bridge deck cracking is a common problem throughout the United States. Early age cracking develops shortly after the deck is poured. It reduces the serviceability and lifespan of bridges. Early age cracking can be typically attributed to either of two factors, 1) construction practices, and 2) shrinkage. The Arkansas Department of Transportation (ARDOT) has experienced early age bridge deck cracking. ARDOT currently specifies a sequence deck pour on most of their bridges; however, contractors prefer continuous deck pours because of ease and construction time. During the period of this TRC1903 research project, ARDOT has only approved a few continuous pours for relatively short bridges, 180 to 190 ft. long. Concrete cracking occurs when concrete tensile stresses exceed the concrete's tensile strength. Therefore, early age bridge deck cracking is evaluated in this thesis be monitoring induced concrete tensile stresses and comparing these values with the concrete's concurrent tensile strength. Bridge site visits at bridges constructed using a continuous deck pour process were conducted to study deck cracking patterns in newly constructed bridges and identify deck sections that were experiencing cracking. In addition to a visual approach for identifying sections experiencing cracking, a numerical method was used. Finite element bridge models were created using ABAQUS to compare numerical modeling results to field recorded results attained from a bridge instrumented with strain gauges cast inside the concrete deck. Additional numerical models were made to verify the modeling techniques used by the author by validating calculated stresses with numerical models in the literature. The Finite element models were specifically developed to model the bridge deck construction process. Therefore, time dependent loads and material properties were considered in the numerical model. Concrete material time dependency was estimated using the Eurocode specifications (CEN., 1992). In addition, concrete stresses were calculated in this thesis using the Eurocode modular ratio approach.
Book Synopsis Evaluation of Early-age Cracking Sensitivity in Bridge Deck Concrete by :
Download or read book Evaluation of Early-age Cracking Sensitivity in Bridge Deck Concrete written by and published by . This book was released on 2008 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Mitigation of Early Age Cracking of Concrete for Bridge Decks by :
Download or read book Mitigation of Early Age Cracking of Concrete for Bridge Decks written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Experimetal Analysis of Early Age Transverse Cracking of Composite Bridge Decks by : Matthew D. LaPlante
Download or read book Experimetal Analysis of Early Age Transverse Cracking of Composite Bridge Decks written by Matthew D. LaPlante and published by . This book was released on 2011 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Control of Cracking in Bridge Decks by : D. Darwin
Download or read book Control of Cracking in Bridge Decks written by D. Darwin and published by . This book was released on 2004 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: Crack surveys of bridge decks, performed over a 10-year period in northeast Kansas as part of three studies, provide strong guidance in identifying the parameters that control cracking in these structures. The surveys involve steel girder bridges--bridges that are generally agreed to exhibit the greatest amount of cracking in the concrete decks. The surveys include monolithic decks and decks with silica fume and conventional concrete overlays. The study demonstrates that crack density increases as a function of cement and water content, and concrete strength. In addition, crack density is higher in the end spans of decks that are integral with the abutments than decks with pin-ended supports. Most cracking occurs early in the life of a bridge deck, but continues to increase over time. This is true for bridges cast in both the 1980s and the 1990s. A key observation, however, is that bridge decks cast in the 1980s exhibit less cracking than those in the 1990s, even with the increase in crack density over time. Changes in materials, primarily cement fineness, and construction procedures over the past 20 years, are discussed in light of these observations. A major bright spot has been the positive effect of efforts to limit early evaporation, suggesting that the early initiation of curing procedures will help reduce cracking in bridge decks.
