Download or read book Comparison of Crack Performance of Structural Slab Bridge Decks with Stringer Supported Bridge Decks written by Michael A. Adams and published by . This book was released on 2011 with total page 113 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of several cracks on reinforced concrete bridge decks is a serious, growing problem that not only affects the state of Ohio, but also the United States as a whole. Many bridge decks constructed within the last 10 years in Ohio have already shown varying levels and patterns of cracking. Regardless of the bridge design type, length of the spans, deck thickness, and concrete mixture designs, cracks will develop on reinforced concrete bridge decks. Bridge deck cracking is a critical issue because cracks allow harmful and corrosive chemicals to penetrate the concrete and deteriorate the reinforcing steel that is embedded in the concrete. If proper precautions and steps are not taken, then this could lead to rapid deterioration leading to costly maintenance problems and need for possible replacement. The Ohio Department of Transportation's current bridge inspection procedure requires periodic inspections of the whole bridge. ODOT's inspection procedure only offers a qualitative assessment of the bridge and does not give a quantitative measurement of the bridge deck cracking. The primary objective of this report was to evaluate the cracking performance of structural slab bridge decks and compare with that of bridges constructed with stringer supports in the ODOT's District 3. Extensive crack surveys were completed for six bridge decks, three structural slab supported bridges and three stinger supported bridges. Crack densities were then determined based on the crack maps corresponding to the surveys for each bridge deck. These crack densities revealed that the structural slab supported bridge decks had a higher propensity for cracking than the bridge decks constructed using stringer supports. Also, since the six bridges surveyed have been constructed within the last two years, a definitive relationship between the age of the bridge and the cracking performance of the bridge deck is not yet evident.

Download or read book Quantification of Cracks in Reinforced Concrete Bridge Decks written by Saikrishna Ganapuram and published by . This book was released on 2013 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cracking in reinforced concrete bridge decks is a widespread concern in the United States. Many concrete bridge decks, regardless to the age of construction, have shown different levels and patterns of cracking. Not only does cracking of bridge decks weaken the bridge infrastructure, but also allows the inflow of corrosive agents into the reinforcement, regardless of the bridge design type, length of spans, deck thickness and concrete mixture designs. Increased cracking of concrete bridge decks all over the world poses a threat to life as well as prove extremely expensive for repair and maintenance. Thus, precautions must be taken in order to avoid and restrict bridge deck cracking, one of which is inspection of the bridge at regular intervals. The Ohio Department of Transportation's current procedure for bridge inspection offers only a qualitative assessment of the bridges inspected. In this study, a method was developed for the quantification of crack densities for twelve bridges in District 3. Two types of bridges were inspected: three structural slab bridge decks and nine stringer supported bridge decks. Crack densities for each bridge were determined based on crack maps corresponding to the surveys for each bridge deck. Results indicated that structural slab bridge decks have slightly higher shrinkage crack densities compared to the bridge decks constructed with stringer supports. However, the "structural" cracks seem to be wider than shrinkage cracks for structural slabs (greater than 0.007 inch). Particularly on bridge ASD-42-0656, which is a continuous slab bridge, there were several large "structural" cracks that were parallel to the pier beams supports. The shrinkage crack densities of the twelve bridge decks determined in this study were considerably lower than the crack densities of similar bridge decks located in other states, demonstrating that Ohio bridge decks in general have lower crack density than those in other states. The shrinkage crack densities of the bridges constructed with QC/QA type of concrete have lower values than the bridges made with other types of concrete. Also, the crack widths were determined at certain key locations and were compared with theoretical values. The measured crack widths are much larger compared to the corresponding theoretical crack widths. This is a reason for concern.

Download or read book Quantification of Cracks in Concrete Bridge Decks in Ohio District 3 written by Sai Ganapuram and published by . This book was released on 2012 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of cracks in reinforced bridge decks is a critical problem, not only in Ohio state, but the whole of United States. Many bridge decks constructed within the last 10 years in Ohio have already shown varying levels and patterns of cracking. Bridge deck cracking is a serious issue because cracks allow harmful and corrosive chemicals to penetrate the concrete and deteriorate the reinforcing steel embedded in it, regardless of the bridge design type, length of spans, deck thickness and concrete mixture designs. Proper precautions need to be taken to avoid rapid deterioration of the bridges which can lead to increased maintenance costs and the need for possible replacement. The Ohio Department of Transportation's current procedure for bridge inspection requires periodic surveying of the whole bridge. However, this inspection procedure offers only a qualitative assessment of the bridges inspected. In this study, a quantitative measurement strategy was adopted by measuring the crack densities of twelve bridges in District 3. Two types of bridges were inspected: three structural slab bridge decks and nine stringer supported bridge decks. Crack densities were determined based on crack maps corresponding to the surveys for each bridge deck. The crack densities determined for the twelve bridge decks indicated that structural slab bridge decks have slightly higher shrinkage crack densities compared to the bridge decks constructed with stringer supports. However, the "structural" cracks seem to be wider for structural slabs (greater than 0.007 inch). Particularly on bridge ASD-42-0656, which is a continuous slab bridge, there were several large "structural" cracks that were parallel to the intermediate supports. These cracks were very wide (much greater than 0.007 inch). The shrinkage crack densities of the twelve bridge decks determined in this study were considerably lower than the crack densities of similar bridge decks located in other states, demonstrating that Ohio bridge decks in general have lower crack density than those in other states. The shrinkage crack densities of the bridges constructed with QC/QA type of concrete have lower values than the bridges made with other types of concrete.

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 Cracking Behavior of Structural Slab Bridge Decks written by Anil Patnaik and published by . This book was released on 2014 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bridge deck cracking is a common problem throughout the United States, and it affects the durability and service life of concrete bridges. Several departments of transportation (DOTs) in the United States prefer using continuous three-span solid structural slab bridges without stringers over typical four-lane highways. Recent inspections of such bridges in Ohio revealed cracks as wide as 0.125 in. These measured crack widths are more than ten times the maximum limit recommended in ACI 224R-01 for bridge decks exposed to de-icing salts. Measurements using digital image correlation revealed that the cracks widened under truck loading, and in some cases, the cracks did not fully close after unloading. This dissertation includes details of an experimental investigation of the cracking behavior of structural concrete. Prism tests revealed that the concrete with epoxy-coated bars (ECB) develops the first crack at smaller loads, and develops larger crack widths compared to the corresponding specimens with uncoated (black) bars. Slab tests revealed that the slabs with longitudinal ECB developed first crack at smaller loads, exhibited wider cracks and a larger number of cracks, and failed at smaller ultimate loads compared to the corresponding test slabs with black bars. To develop a preventive measure, slabs with basalt and polypropylene fiber reinforced concrete were also included in the test program. These test slabs exhibited higher cracking loads, smaller crack widths, and higher ultimate loads at failure compared to the corresponding slab specimens without fibers. Merely satisfying the reinforcement spacing requirements given in AASHTO or ACI 318-11 is not adequate to limit cracking below the ACI 224R-01 recommended maximum limit, even though all the relevant design requirements are otherwise met. Addition of fiber to concrete without changing any steel reinforcing details is expected to reduce the severity and extent of cracking in reinforced concrete bridge decks.

Download or read book Performance and Constructability of Silica Fume Bridge Deck Overlays written by Gerald G. Miller and published by . This book was released on 2000 with total page 478 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effects of construction practices and material properties on the performance of concrete bridge decks are evaluated. Emphasis is placed on comparing bridge decks with silica fume and conventional concrete overlays and determining if the silica fume overlays commonly used on bridges in Kansas are performing at a level that justifies the extra cost and construction precautions. Forty continuous steel girder bridges, 20 with silica fume overlays, 16 with conventional overlays and four with monolithic bridge decks are included in the study.

Download or read book Transverse Cracking of High Performance Concrete Bridge Decks After One Season Or Six to Eight Months written by and published by . This book was released on 2006 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cracking is a major problem with newly placed concrete decks. These decks tend to develop full depth, transverse cracks and partial depth longitudinal cracks within a few months of the concrete being placed. A literature review showed that several other states had experienced similar problems. A review of data from Ohio bridge decks showed weak correlations between deck cracking and slump, time of year when the deck was placed, shrinkage, chloride permeability and compressive strength, but there was no clear relationship between cracking and any of these properties. Data also suggested that using a coarse aggregate with an absorption> 1% may help mitigate deck cracking but will not always stop it. As part of this study, 3 bridge decks were instrumented. One was a standard class "S" concrete deck and the other two were high performance concrete. The class "S" deck showed only hairline cracking after 1 year, but transverse cracking occurred in the HPC decks. Instruments were placed in the decks to monitor strains. From the data, it appears that cracking is caused by several factors. High heat of hydration caused the plastic concrete to expand. When the concrete sets and cools, tensile stressed develop. Further tensile stresses develop through drying shrinkage. Restraining the deck against normal thermal movement contributes to additional tensile stress. Autogeneous shrinkage, where high heats of hydration cause water evaporation during hydration, and plastic shrinkage may cause more tensile stress. Recommendations for mitigating cracking include using lower cement contents, adding pozzolans and retarders, using slightly higher water/cement ratios, using larger aggregates, taking steps to limit shrinkage and eliminating restraints.

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 Comparative Study Between Steel free and Steel Reinforced Concrete Bridge Deck Slabs Subjected to Fatigue Loading written by Cody Scaletta and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This experimental program was designed to provide increasing evidence that second generation steel-free concrete bridge decks are a practical alternative to conventional steel reinforced concrete bridge decks. The bridge deck in this experiment was cast monolithically with one half consisting of a second generation steel-free concrete bridge deck and the second half a conventional steel reinforced concrete bridge deck. A constant cyclic load was applied to each segment at an identical magnitude to compare the two bridge decks in terms of endurance, durability, deflection, crack width, reinforcement strain, concrete strain, and overall performance. The test results obtained in this experimental program confirm the notion that second generation steel-free concrete bridge decks are a safe and reliable alternative to conventional steel reinforced concrete bridge decks, and furthermore should become more widely accepted and practiced in the field of bridge engineering. The mode of failure for both segments was punching shear failure.

Download or read book Construction of Low cracking High performance Bridge Decks Incorporating New Technology written by James Lafikes and published by . This book was released on 2020 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: Construction and early-age crack evaluations of four bridge decks in Minnesota placed from 2016 to 2018 that incorporate specifications for Internally-Cured Low-Cracking High-Performance Concrete (IC-LC-HPC) are documented in this study. Two additional decks followed specifications for high-performance concrete and served as controls paired with IC-LC-HPC decks. Pre-wetted fine lightweight aggregate (FLWA) was used to provide a targeted internal curing water content of 8% by total weight of binder. The IC-LC-HPC mixtures included 27 to 30% slag cement by total binder weight while the control mixtures included 25 or 35% Class F fly ash by total weight of binder. For one IC-LC-HPC deck, mixture proportions were modified based on a higher FLWA absorption than originally used to design the mixture. One IC-LC-HPC placement failed due to errors in FLWA moisture corrections and concrete batching that led to rejections of batches, leaving an inadequate supply of material to complete the deck. Crack surveys were completed for the IC-LC-HPC and control decks placed in 2016 and 2017. Crack densities at these ages were low compared to most Low-Cracking High-Performance Concrete decks in Kansas and Internally-Cured High-Performance Concrete decks in Indiana. The only exception was one IC-LC-HPC deck that exhibited extensive cracking within one year after placement, which had an overlay with a high cement paste content and no internal curing. This project serves as a foundation for implementing IC-LC-HPC in upcoming bridge decks in Kansas and Minnesota.

Download or read book Bridge Deck Analysis written by Damien L. Keogh and published by CRC Press. This book was released on 2005-08-09 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: The definitive text in the field of Bridge Deck behaviour and analysis Bridge Deck Analysis is an essential reference for civil and structural engineers. It provides bridge designers with the knowledge to understand the behaviour of bridge decks, to be familiar with, and to understand the various numerical modelling techniques, to know which technique is most suited. The book covers the grillage analogy, dedicates a chapter to the modelling and analysis of integral bridge forms and also provides guidance of the application of the finite element method.

Download or read book Concrete Bridge Deck Performance written by H. G. Russell and published by Transportation Research Board. This book was released on 2004 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: At head of title: National Cooperative Highway Research Program.

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 In service Performance of HP Concrete Bridge Decks written by Frank T. Owens and published by . This book was released on 1999 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Construction of Crack free Bridge Decks written by David Darwin and published by . This book was released on 2017 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt: This serves as the final report on Transportation Pooled-Fund Program Project No. TPF-5(174), "Construction of Crack-Free Bridge Decks." The goal of the study was to implement the most cost-effective techniques for improving bridge deck life through the reduction of cracking. Work was performed both in the laboratory and in the field, resulting in the construction of 17 bridge decks in Kansas that were let under Low-Cracking High-Performance Concrete (LC-HPC) specifications. The report documents the performance of the decks based on crack surveys performed on the LC-HPC decks and matching control bridge decks. The specifications for LC-HPC bridge decks, which cover aggregates, concrete, and construction procedures, as well as procedures for performing crack surveys, are summarized. The first 13 LC-HPC bridge decks are compared to control decks in terms of crack density as a function of time. Survey results are also presented for three LC-HPC decks without control decks and one deck let under LC-HPC specifications on which the specifications were not enforced. The widths of measured cracks ranged from 0.006 to 0.025 inches (0.15 to 0.64 mm). The LC-HPC bridge decks exhibit less cracking than the matching control decks in the vast majority of cases. Only bridge decks LC-HPC-2 and LC-HPC-3 have higher overall crack densities than their control decks, the two best performing control decks in the program, and the differences are small. The majority of the cracks are transverse and run parallel to the top layer of the deck reinforcement. Relatively short cracks are present near the abutments and propagate perpendicular to the abutments (longitudinally). The study demonstrates the positive effects of reduced cementitious material and cement paste contents, improved early-age and long-term curing, concrete temperature control, limitations on or de-emphasis of maximum concrete compressive strength, limitations on maximum slump, and minimizing finishing operations on minimizing cracking in bridge decks.

Download or read book Reduction of Bridge Deck Cracking Through Alternative Material Usage written by Anil Patnaik and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ODOT routinely deploys a large number of continuous span structural slab bridges. Despite being designed to strictly satisfy all the relevant AASHTO and ODOT BDM requirements, many such bridge decks show transverse cracks, with widths greater than those predicted using AASHTO 2012 and ACI 318-14 guidelines, after being in service for less than one year. The addition of polypropylene fiber to deck concrete has the potential to reduce such cracking. The overall goal of this project was to identify materials and methods to reduce the extent and severity of deck cracking for structural slab bridges and determine the effectiveness of fiber for this purpose. From the crack surveys of 30 bridges in various ODOT districts, sampled from the 63 bridges suggested from the bridge inventory, it was found that crack widths of transverse cracks were in excess of the recommended limit of 0.007" on 26 of the surveyed bridges. Meeting the maximum crack width limit of 0.007" for bridge decks reinforced with epoxy-coated bars is unrealistic and unachievable with current ODOT practices, and this limit may need to be reconsidered. The addition of fiber to deck concrete without any changes to the reinforcement details of continuous span structural slab bridges was determined to reduce the extent and the severity of cracking by a factor of about 3 to 4, making it plausible to reduce crack widths in future bridge decks. The beneficial effects of fiber primarily stem from the improved performance of the concrete with fiber under freeze-thaw and sustained loading as well as from the enhanced response of concrete to static and fatigue loading. The ease of placement, effective consolidation and acceptable finish achieved with concrete incorporating polypropylene fiber at a rate of 10 lb/yd3 in a pilot bridge in Medina County (Ohio) makes the proposed solution implementable by ODOT without any deviations from the current practices except for the addition of fiber to deck concrete.

Download or read book Construction of Low cracking High performance Bridge Decks Incorporating New Technology Phase II written by Alireza Bahadori and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The construction, crack surveys, and evaluation of 12 bridge decks with internal curing provided by prewetted fine lightweight aggregate and supplementary cementitious materials following internally cured low-cracking high-performance concrete (IC-LC-HPC) specifications of Minnesota or Kansas are described, as well as those from two associated Control decks without IC (MN-Control). Nine IC-LC-HPC decks and one Control deck were monolithic, while three IC-LC-HPC decks and one Control deck had an overlay. The internally cured low-cracking high-performance concrete had paste contents between 23.8 and 25.8 percent by volume. Of the 12 IC-LC-HPC decks, nine were constructed in Minnesota between 2016 and 2020, and three were constructed in Kansas between 2019 and 2021. The performance of the decks is compared with that of earlier IC-LC-HPC bridge decks and low-cracking high-performance concrete (LC-HPC) bridge decks without internal curing. The effects of construction practices on cracking are addressed. The results indicate that the use of overlays on bridge decks is not beneficial in mitigating cracking. The IC-LC-HPC decks constructed exhibited lower average crack densities than those without internal curing. Good construction practices are needed for low-cracking decks. If poor construction practices, which may include poor consolidation and disturbance of concrete after consolidation, over-finishing, delayed application of wet curing, are employed, even decks with low paste contents and internal curing can exhibit high cracking. Delayed curing and over-finishing can also result in scaling damage to bridge decks.