Download or read book Post tensioning the Inverted t Bridge System for Improved Durability and Increased Span to depth Ratio written by Rim Nayal and published by . This book was released on 2007 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: Possibly the most pressing need in highway construction today is the repair or replacement of existing bridges. Due to increased needs and growing traffic, in addition to aging and extensive use, more than 2000 bridges in Kansas alone need to be replaced during the next decade. The majority of these bridges has spans of 100 ft or less, and has relatively shallow profiles. It is becoming increasingly important to implement a standard method for replacement in which the process is expedited and accomplished in cost-effective manner. Requirements for design and construction of concrete bridges have drastically changed during recent years. A main change in design is live-load requirements. Nebraska inverted-T bridge system has gained increasing popularity for its lower weight compared to I-girder bridges. However, there are some limiting issues when using IT system in replacing existing CIP bridges. Implementation of a post-tensioned IT system, which is the focus of this research, is believed to be one excellent solution for the IT deficiencies. Post-tensioning is added by placing a draped, post-tensioning duct in the stems of the IT members. Post-tensioning will lead to a higher span-to-depth ratio than IT system, and will reduce the potential transverse cracks in the (CIP) deck. Finally, the undesired cambers of pretensioned beams will be reduced, because fewer initial prestressing will be needed. This study was intended to explore the behavior of the PT-IT system, identify major parameters that control and limit the design of this system, and investigate different construction scenarios. This was achieved by conducting an extensive parametric study. For that purpose, PT-IT analysis program was developed and written using C++ programming language. The program was used to analyze various post-tensioning procedures for the post-tensioned inverted-T system. A Visual Basic friendly interface was provided to simplify the data input process. The findings of this research included recommendation of construction scenario for PT-IT system, as well as examining different methods for estimating time-dependent restraining moments. Effect of different concrete strengths on the behavior of PT-IT system was also determined. Most importantly, the effect of timing on different construction stages was also evaluated and determined.
Download or read book Improving the Durability of the Inverted T beam Bridge System written by Carin Louise Roberts-Wollmann and published by . This book was released on 2018 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt: The inverted T‐beam system provides an accelerated bridge construction alternative. The system consists of adjacent precast inverted T‐beams finished with a cast‐in‐place concrete topping. The system offers enhanced performance against reflective cracking and reduces the likelihood of cracking due to time dependent effects. Differential shrinkage is believed to be one of the causes of deck cracking in inverted T‐beam systems. The objective of this study was to develop mix designs that exhibit lower shrinkage and higher creep compared to typical deck mixtures, recommend a prescriptive mix design and a performance criterion to VDOT that can be used in the inverted T‐beam system to combat effects of differential shrinkage. Ten different mix designs using different strategies to reduce shrinkage were tested for their compressive strength, splitting tensile strength, modulus of elasticity and unrestrained shrinkage. The four best performing mixes were selected for further study of their time dependent properties. The test data was compared against the data from various prediction models to determine the model that closely predicts the measured data. It was observed that ACI 209.2R‐08 model best predicted the time dependent properties for the four mixes tested in this project. Tensile stresses in the composite cross‐ section of deck and girder, created due to difference in shrinkage and creep were quantified using an age adjusted effective modulus method. In this analysis, it was observed that mixes with normal weight coarse aggregate developed smaller stresses compared to those of mixes with lightweight coarse aggregate. Mixes with fly ash as supplementary cementitious material (SCM) developed smaller stresses at the bottom of deck when compared to mixes with slag as the SCM.
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2007 with total page 924 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Post Tensioning Technologies written by Ryan W. Jenkins and published by Joint Transportation Research Program. This book was released on 2013-10 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: Post-tensioned bridge construction has become increasingly popular and financially competitive with traditional prestressed concrete and steel plate girder bridges. Unfortunately, Indiana has experienced several construction-related problems in the few post-tensioned structures built, some of which have caused significant long-term durability concerns. Indiana's problems have generally been attributed to a lack of a standard set of specifications for post-tensioned construction as well as inexperience and inadequate training of contractors and inspectors. These types of issues, however, were once more prevalent throughout the industry and much work has been accomplished in recent years to address these issues. This research program had two primary objectives: (1) to improve the quality of post-tensioned bridge construction in Indiana and (2) to provide the State with more confidence when using this type of construction. First, past problems related to post-tensioned construction were identified, and for each, case studies were conducted. Each case study includes an overview of the bridge, a summary of the problems related to post-tensioning, and possible sources and remedies to those problems. Next, a standard post-tensioning construction specification was developed. The specification addresses problems specific to Indiana which were found in the case studies and common problems experienced in the industry as a whole. Specifically, the specification addresses industry standards of practice, requirements for certification and experience of personnel, and proper testing and sampling procedures. In addition, specific recommendations are provided for training programs and certification of INDOT construction personnel to ensure they are properly trained to inspect post-tensioned construction.
Download or read book Interim Conclusions Recommendations and Design Guidelines for Durability of Post tensioned Bridge Substructures written by and published by . This book was released on 1999 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Canadian Journal of Civil Engineering written by and published by . This book was released on 2003 with total page 602 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Engineer written by and published by . This book was released on 1859 with total page 522 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book HRIS Abstracts written by National Research Council (U.S.). Highway Research Board and published by . This book was released on 1985 with total page 1254 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Highway Engineer written by and published by . This book was released on 1968 with total page 594 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Railway Gazette written by and published by . This book was released on 1959-04 with total page 1066 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Engineering for Structural Stability in Bridge Construction written by Federal Highway Federal Highway Administration and published by . This book was released on 2020-07-19 with total page 669 pages. Available in PDF, EPUB and Kindle. Book excerpt: This manual is intended to serve as a reference. It will provide technical information which will enable Manual users to perform the following activities:Describe typical erection practices for girder bridge superstructures and recognize critical construction stagesDiscuss typical practices for evaluating structural stability of girder bridge superstructures during early stages of erection and throughout bridge constructionExplain the basic concepts of stability and why it is important in bridge erection* Explain common techniques for performing advanced stability analysis along with their advantages and limitationsDescribe how differing construction sequences effect superstructure stabilityBe able to select appropriate loads, load combinations, and load factors for use in analyzing superstructure components during constructionBe able to analyze bridge members at various stages of erection* Develop erection plans that are safe and economical, and know what information is required and should be a part of those plansDescribe the differences between local, member and global (system) stability
Download or read book Construction Handbook for Bridge Temporary Works written by American Association of State Highway and Transportation Officials and published by American Association of State Highway & Transportation Officials. This book was released on 1995 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Prefabricated Bridge Elements and Systems to Limit Traffic Disruption During Construction written by Mohsen Shahawy and published by Transportation Research Board. This book was released on 2003 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: TRB's National Cooperative Highway Research Program (NCHRP) Synthesis Report 324: Prefabricated Bridge Elements and Systems to Limit Traffic Disruption During Construction assesses and documents the use of innovative prefabricated elements and systems and assesses its effects on on-site construction time and cost, closure time, and environmental impacts. The synthesis report also looks at the use of fiber-reinforced polymers and other advanced materials and new technologies that are gaining in popularity but are still in the experimental stages.
Download or read book Railroad Gazette written by and published by . This book was released on 1891 with total page 970 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Examples for the Design of Structural Concrete with Strut and tie Models written by American Concrete Institute. Convention and published by . This book was released on 2002 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Prepared by members of ACI Subcommittee 445-1, Strut and Tie Models, for sessions at the Fall Convention in Phoenix, October 27 to November 1, 2002, and sponsored by Joint ACI-ASCE Committee 445, Shear and Torsion and ACI Committee 318-E, Shear and Torsion."
Download or read book Structural Engineering Handbook Fifth Edition written by Mustafa Mahamid and published by McGraw Hill Professional. This book was released on 2020-04-17 with total page 957 pages. Available in PDF, EPUB and Kindle. Book excerpt: Publisher's Note: Products purchased from Third Party sellers are not guaranteed by the publisher for quality, authenticity, or access to any online entitlements included with the product. The industry-standard guide to structural engineering—fully updated for the latest advances and regulations For 50 years, this internationally renowned handbook has been the go-to reference for structural engineering specifications, codes, technologies, and procedures. Featuring contributions from a variety of experts, the book has been revised to align with the codes that govern structural design and materials, including IBC, ASCE 7, ASCE 37, ACI, AISC, AASHTO, NDS, and TMS. Concise, practical, and user-friendly, this one-of-a-kind resource contains real-world examples and detailed descriptions of today’s design methods. Structural Engineering Handbook, Fifth Edition, covers: • Computer applications in structural engineering • Earthquake engineering • Fatigue, brittle fracture, and lamellar tearing • Soil mechanics and foundations • Design of steel structural and composite members • Plastic design of steel frames • Design of cold-formed steel structural members • Design of aluminum structural members • Design of reinforced- and prestressed-concrete structural members • Masonry construction and timber structures • Arches and rigid frames • Bridges and girder boxes • Building design and considerations • Industrial and tall buildings • Thin-shell concrete structures • Special structures and nonbuilding structures
