Incidence Assessment of Transverse Cracking in Concrete Bridge Decks: Construction and material considerations PDF Download

Author:
Publisher:
ISBN:
Category : Concrete bridges
Languages : en
Pages :

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Book Description
A survey of transverse cracking in 72 recently completed concrete bridge decks in the Piedmont region of North Carolina.

Author:
Publisher:
ISBN:
Category : Concrete bridges
Languages : en
Pages :

View

Book Description
A survey of transverse cracking in 72 recently completed concrete bridge decks in the Piedmont region of North Carolina.

Author:
Publisher:
ISBN:
Category : Concrete bridges
Languages : en
Pages :

View

Book Description
A survey of transverse cracking in 72 recently completed concrete bridge decks in the piedmont region of North Carolina.

Author: Paul D. Krauss
Publisher:
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 136

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Author: M. Ala Saadeghvaziri
Publisher:
ISBN:
Category : Concrete bridges
Languages : en
Pages : 206

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Book Description
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.

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Languages : en
Pages : 0

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Transverse cracking of concrete bridge decks continues to be an issue for the Montana Department of Transportation (MDT) and is considered a common issue reported among many state departments of transportation (DOTs). In the last 25 years with the introduction of high performance concrete (HPC) in bridge decks to lower permeability and with the use of finer ground cements (to increase early age strength gain and construction schedule), the susceptibility of bridge deck cracking has increased. Cracking commonly leads to a reduction in service life and increased maintenance costs, primarily due to accelerated corrosion of reinforcing steel in the deck. Identifying the causes of bridge deck cracking and providing prevention can be complex and challenging, but is very important for maintaining longevity of the bridge deck. To assist MDT with diagnosing and mitigating the causes of transverse cracking of bridge decks, WJE implemented a multi-disciplinary approach including a literature review, field inspections, bridge deck instrumentation, laboratory evaluations, and finite element modeling (FEM). From this research, WJE found the primary causes were related to non-uniform moisture gradients, drying shrinkage, and specific winter curing procedures. Based on these findings, WJE recommended improvements to mixture proportions, construction practices, and design considerations.

Author: Tony R. Schmitt
Publisher:
ISBN:
Category : Concrete bridges
Languages : en
Pages : 174

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Book Description
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.

Author: H. G. Russell
Publisher: Transportation Research Board
ISBN: 0309070112
Category : Bridges
Languages : en
Pages : 188

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Book Description
At head of title: National Cooperative Highway Research Program.

Author: Levon Minnetyan
Publisher:
ISBN:
Category : Concrete bridges
Languages : en
Pages : 166

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This research project investigated stresses in high performance (HP) concrete composite bridge decks due to temperature, shrinkage, and vehicle loading. Computational methods and software were developed to compute the stresses. The structural analysis program used a layered finite element model. Time-history residual stresses were computed for 28 days, then an HS25 vehicle load was applied. Longitudinal stress levels were printed layer by layer for comparison with the modulus of rupture and assessment of cracking.

Author:
Publisher:
ISBN:
Category : Concrete
Languages : en
Pages : 112

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Book Description
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.