Author: Publisher:
ISBN:
Category : Pavements
Languages : en
Pages : 276
Book Description
Maintenance and Repair Practices for Pavements
Author: Concrete Bridge Deck Performance
Author: H. G. RussellPublisher: Transportation Research Board
ISBN: 0309070112
Category : Bridges
Languages : en
Pages : 188
Book Description
At head of title: National Cooperative Highway Research Program.
Guidelines for Concrete Mixtures Containing Supplementary Cementitious Materials to Enhance Durability of Bridge Decks
Author: John S. LawlerPublisher: Transportation Research Board
ISBN: 0309098971
Category : Aggregates (Building materials)
Languages : en
Pages : 130
Book Description
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.
Guide for Curing of Portland Cement Concrete Pavements
Author: Toy S. PoolePublisher:
ISBN:
Category : Concrete
Languages : en
Pages : 174
Book Description
Curing Concrete
Author: Peter C. TaylorPublisher: CRC Press
ISBN: 0415779529
Category : Technology & Engineering
Languages : en
Pages : 220
Book Description
Curing is one of those activities that every civil engineer and construction worker has heard of, but in reality does not worry about much. In practice, curing is often low on the list of priorities on the construction site, particularly when budgets and timelines are under pressure. Yet the increasing demands being placed on concrete mixtures also mean that they are less forgiving than in the past. Therefore, any activity that will help improve hydration and so performance, while reducing the risk of cracking, is becoming more important. Curing Concrete explains exactly why curing is so important and shows you how to best do it. The book covers: The fundamentals behind hydration How curing affects the properties of concrete, improving its long-term performance What curing technologies and techniques you can use for different applications How to effectively specify, provide, and measure curing in a project The author also gives numerous examples of how curing—or a lack of it—has affected concrete performance in real-world situations. These include examples from hot and cold climates, as well as examples related to high-performance concrete, performance parameters, and specifications and testing. Written for construction professionals who want to ensure the quality and longevity of their concrete structures, this book demonstrates that curing is well worth the effort and cost.
Transverse Cracking of High Performance Concrete Bridge Decks After One Season Or Six to Eight Months
Author: Publisher:
ISBN:
Category : Concrete
Languages : en
Pages : 112
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.
Technologies for Improving the Evaluation and Repair of Concrete Bridge Decks
Author: Report
Author: ACI Manual of Concrete Practice
Author: American Concrete InstitutePublisher:
ISBN:
Category : Concrete
Languages : en
Pages : 1294
Book Description
Long-term Performance of Polymer Concrete for Bridge Decks
Author: David W. FowlerPublisher: Transportation Research Board
ISBN: 0309143543
Category : Technology & Engineering
Languages : en
Pages : 75
Book Description
TRB's National Cooperative Highway Research Program (NCHRP) Synthesis 423: Long-Term Performance of Polymer Concrete for Bridge Decks addresses a number of topics related to thin polymer overlays (TPOs). Those topics include previous research, specifications, and procedures on TPOs; performance of TPOs based on field applications; the primary factors that influence TPO performance; current construction guidelines for TPOs related to surface preparation, mixing and placement, consolidation, finishing, and curing; repair procedures; factors that influence the performance of overlays, including life-cycle cost, benefits and costs, bridge deck condition, service life extension, and performance; and successes and failures of TPOs, including reasons for both.