Download or read book Behavior of Concrete Bridge Decks Under Combined Shrinkage Thermal and Live Loading written by Anuoluwa Adediji and published by . This book was released on 2016 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: Designers have consistently been concerned with long term deformation of bridges to mitigate unfavorable effects such as excessive movement and cracking. Furthermore, any developed tool of use to a designer must make use of parameters known at the time of design as well as be simplistic in nature as defined in the code. As such, many prediction models for the free shrinkage of a concrete specimen have been developed toward this end. However, structures designed and placed in the field experience shrinkage under restraint. Also, the differences in environmental conditions affect the shrinkage of structures. It is important to understand the restrained shrinkage of structures under field conditions and use this understanding to make improved guidelines on shrinkage from a design standpoint. In this study, the prediction and modelling of the free shrinkage of small samples under constant conditions were expanded to the prediction and modelling of restrained shrinkage under field conditions of large samples using finite element analysis. A parametric analysis was then performed to derive useful information from a design perspective such as the impact of various design parameters on the performance of a bridge deck. The findings indicated that the use of reinforcement is the preferable method of addressing shrinkage in bridge decks. Furthermore, the efficacy of the amount of reinforcement specified in the AASHTO guidelines to mitigate excessive cracking in bridge decks was discussed. The traditional and empirical methods of bridge deck design were investigated for shrinkage reinforcement. Finally, recommendations were suggested to the reinforcement requirements based on the findings of this study.
Download or read book Behavior of Bridge with Internally Cured Concrete Deck Under Environmental and Truck Loading written by Waleed Khalid Hamid and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The long-term performance of a bridge deck depends on its resistance to bridge cracking. Most of these cracks are initiated at the early age. Early age cracking of bridge decks is a typical issue in the U.S. that reduces bridge service life. Therefore, internally cured concrete (ICC) has been used in some states to reduce or eliminate the development of cracks in reinforced concrete decks. In this study, the early age behavior of ICC deck and the effect of the internal curing on the long-term behavior of the bridge was measured and evaluated in the laboratory and field for newly adjacent constructed bridge, which were located on Route 271 in Mayfield, Ohio. Two different types of concrete mixtures were utilized for the decks: conventional concrete (CC) and internally cured concrete (ICC). Firstly, the ICC and CC mixtures were examined in the laboratory in terms of a mechanical properties test, a plastic shrinkage test, a free shrinkage test, and a restrained shrinkage test. Second, the field behavior of an ICC deck and an adjacent CC deck during their early age and long-term performance were evaluated. Also, the shrinkage development for both decks was examined during the very early age. Instrumentation was used to measure the concrete and reinforcement strains and the temperature in both bridges. The instrumentation and results for both bridges are discussed. Laboratory results indicated that using pre-wetted lightweight concrete in the concrete mixture led to decreased density, coefficient of thermal expansion, and free shrinkage strain, and increased tensile strength and cracking time of concrete compared to conventional concrete. In the field, from the early age test, it was observed that the time to develop concrete shrinkage was approximately 5-6 hours after casting the deck of the ICC and the CC.
Download or read book High Performance Concrete Bridge Decks A Fast Track Implementation Study Volume 1 Structural Behavior written by Robert J. Frosch and published by Purdue University Press. This book was released on 2008-11-01 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transverse cracking of concrete bridge decks is problematic in numerous states. Cracking has been identified in the negative and positive moment regions of bridges and can appear shortly after opening the structure to live loads. To improve the service life of the bridge deck as well as decrease maintenance costs, changes to current construction practices in Indiana are being considered. A typical bridge deck was instrumented which incorporated the following: increased reinforcement amounts, decreasing reinforcement spacing, and high-performance, low-shrinkage concrete. The low shrinkage concrete was achieved using a ternary concrete mix. The objective of this research was to determine the performance, particularly in terms of transverse cracking and shrinkage, of a bridge incorporating design details meant to reduce cracking. Based on measurements from the bridge, it was determined that maximum tensile strains experienced in the concrete were not sufficient to initiate cracking. An on-site inspection was performed to confirm that cracking had not initiated. The data was analyzed and compared with the behavior of a similarly constructed bridge built with nearly identical reinforcing details, but with a more conventional concrete to evaluate the effect of the HPC. Based on this study, it was observed that full-depth transverse cracks did not occur in the structure and that the use of HPC lowered the magnitude of restrained shrinkage strains and resulting tensile stresses.
Download or read book Concrete Bridge Deck Behavior Under Thermal Loads written by Jeffrey Keith Johnson and published by . This book was released on 2005 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Behavior of Shrinkage compensating Concretes Suitable for Use in Bridge Decks written by Robert W. Cusick and published by . This book was released on 1976 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Behavior of Shrinkage compensating Concretes Suitable for Use in Bridge Decks by Kim E Seeber Donald L Bartlett and Clyde E Kesler written by Kim E. Seeber and published by . This book was released on 1973 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Behavior of Shrinkage compensating Concretes Suitable for Use in Bridge Decks written by Phillip E. Borrowman and published by . This book was released on 1974 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Behavior of Shrinkage compensating Concretes Suitable for Use in Bridge Decks written by Robert W. Cusick and published by . This book was released on 1977 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Durability of Concrete Bridge Decks written by and published by . This book was released on 1965 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Simulation of the Effect of Deck Cracking Due to Creep and Shrinkage in Single Span Precast prestressed Concrete Bridges written by Sudarshan Chakradhari Kasera and published by . This book was released on 2014 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of precast/prestressed concrete as a structural building system became prominent in the 1950s especially for bridges. The design of the bridge structures was done as simply supported then. In 1969, an analysis and design method for "continuous for live load" bridges was developed. Extensive research has been conducted since then to study the behavior of "continuous for live load" precast/prestresed bridges and various modifications have been proposed. The current analysis method fails to predict the behavior of the continuous precast/prestressed bridge accurately because of the complex loads such as creep and shrinkage. The experimental procedure to determine the behavior of structures due to creep and shrinkage needs time and lot of resources. The motivation behind the current research is to provide a concept where finite element method can be employed to study the behavior of such structures. This research focuses on studying the behavior of single-span precast prestressed bridge due to long-term loading such as creep and shrinkage. The general purpose finite element program, ABAQUS 6.11-2 is used for analysis in the current project. The concept developed from the current research can be applied to multi-span bridge continuous structure in the future. The effect of creep and shrinkage on the overall system is studied. The results obtained from the analyses conform to the observed behavior in the field. It can be said that the analyses procedure for "continuous for live load" bridges needs to account for the cracking of the deck slab to predict an accurate behavior of the structure.
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.
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:
Download or read book Behavior of Shrinkage compensating Concretes Suitable for Use in Bridge Decks written by R. W. Cusick and published by . This book was released on 1976 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Restrained Shrinkage Behavior of Heat cured High Early strength High performance Concrete HES HPC written by Jonathan Eagelton and published by . This book was released on 2014 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: For decades, High Performance Concrete has commonly been used in bridge decks due to its high strength and durability. Despite these properties, cracking in decks continues to be a challenge for bridge engineers. Cracking in bridge decks can lead to weaker structural members, increased damage during freeze-thaw cycles, and accelerated corrosion. These issues lead to more frequent maintenance as the deck needs to be replaced, which raises costs. Causes of cracking includes: harsh weather conditions during pour or curing, high shrinkage stresses, and extremely high live loads due to overweight truck traffic. There is some belief that freshly poured concrete will develop some stress as adjacent lanes are loaded with trucks. Since the concrete is still weak at this stage, it is believed that the strain caused by this stress generation may be large enough to cause cracking. Because of this, the New Jersey Turnpike Authority (NJTA) has recently developed Supplementary Technical Specifications for a High Early Strength HPC (HES-HPC) to replace bridge decks during staged construction. Higher early age strength can be achieved by increasing the rate of hydration, which can be accomplished with higher temperatures. Part of the specifications suggests the use of a heat blanket to keep the concrete at higher temperatures in the early hours to achieve a faster strength gain. Despite this proposition, heat blanket cured concrete has yet to be tested for restrained shrinkage using the ring test. Additionally, shrinkage reducing admixture has yet to be studied for HES-HPC, despite the possibility of its applicability. The restrained shrinkage ring test is used to compare the cracking tendency of HPC, typical HES-HPC, and heat cured HES-HPC. Shrinkage reducing admixture is also studied to determine if it can be practically applied to HES-HPC. Results of the restrained shrinkage test are also correlated with the free shrinkage results. Crack development is monitored throughout the test and used for comparison.
Download or read book Behavior of Field cast Ultra high Performance Concrete Bridge Deck Connections Under Cyclic and Static Structural Loading written by Benjamin A. Graybeal and published by . This book was released on 2010 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The use of modular bridge deck components has the potential to produce higher quality, more durable bridge decks; however, the required connections have often proved lacking, resulting in less than desirable overall system performance. Advanced cementitious composite materials whose mechanical and durability properties far exceed those of conventional concretes present an opportunity to significantly enhance the performance of field-cast connections thus facilitating the wider use of modular bridge deck systems. Ultra-high performance concrete (UHPC) represents a class of such advanced cementitious composite materials. Of particular interest here, UHPCs can exhibit both exceptional bond when cast against previously cast concrete and can significantly shorten the development length of embedded discrete steel reinforcement. These properties allow for a redesign of the modular component connection, facilitating simplified construction and enhanced long-term system performance. This study investigated the structural performance of field-cast UHPC connections for modular bridge deck components. The transverse and longitudinal connection specimens simulated the connections between precast deck panels and the connections between the top flanges of deck-bulb-tee girders, respectively. Testing included both cyclic and static loadings. The results demonstrated that the field-cast UHPC connection facilitates the construction of an emulative bridge deck system whose behaviors should meet or exceed those of a conventional cast-in-place bridge deck"--Technical report documentation page.
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1992 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Behavior of Shrinkage compensating Concretes Suitable for Use in Bridge Decks written by Kim E. Seeber and published by . This book was released on 1973 with total page 61 pages. Available in PDF, EPUB and Kindle. Book excerpt:
