Download or read book Field Measurements on Skewed Semi integral Bridge with Elastic Inclusion written by Edward J. Hoppe and published by . This book was released on 2006 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: This project was designed to enhance the Virginia Department of Transportation's expertise in the design of integral bridges, particularly as it applies to highly skewed structures. Specifically, the project involves extensive monitoring of a semi-integral (integral backwall) bridge with a 45-degree skew. Long-term, continuous monitoring of strains developed in foundation piles, earth pressures exerted on the backwall by the adjacent approach embankment, and concrete buttress reactions preventing the superstructure from rotating in the horizontal plane will be performed. Overall, 120 strain gages, 16 earth pressure cells, and 2 high-capacity load cells, interfaced with electronic dataloggers, will be used in the study. This report provides a record of work carried out from the start of construction in January 2006 to the beginning of May 2006. It specifically describes the instrumentation of the bridge. Future reports will provide an analysis of the results of the field monitoring program. The study is expected to continue for the next 2 years in order to capture the bridge's response over a wide range of climatic conditions.
Download or read book Thermal Response of a Highly Skewed Integral Bridge written by Edward J. Hoppe and published by . This book was released on 2012 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this study was to conduct a field evaluation of a highly skewed semi integral bridge in order to provide feedback regarding some of the assumptions behind the design guidelines developed by the Virginia Department of Transportation. The project was focused on the long term monitoring of a bridge on Route 18 over the Blue Spring Run in Alleghany County, Virginia. The 110 ft long, one span bridge was constructed at a 45 degree skew and with no approach slabs. It incorporated an elasticized expanded polystyrene material at the back of the integral backwall. Bridge data reflecting thermally induced displacements, loads, earth pressures, and pile strains were acquired at hourly intervals over a period of approximately 5 years. Approach elevations were also monitored. Analysis of data was used to formulate design recommendations for integral bridges in Virginia. Field results indicated that semi integral bridges can perform satisfactorily at a 45 degree skew provided some design details are modified. The relatively high skew angle resulted in a pronounced tendency of the semi integral superstructure to rotate in the horizontal plane. This rotation can generate higher than anticipated horizontal earth pressure acting on the abutment wingwall. Study recommendations include modifying the structural detail of the backwall wingwall interface to mitigate crack formation and placing the load buttress close to the acute corner of a highly skewed abutment to reduce the abutment horizontal rotation. The use of elastic inclusion at the back of the semi integral backwall resulted in the reduction of earth pressures and negligible approach settlements. The study recommendations include proposed horizontal earth pressure coefficients for design and a revised approach to calculating the required thickness of the elastic inclusion. While recommending that the existing VDOT guidelines allow an increase in the allowable skew angle from 30 degree to 45 degree for semi integral bridges, the study also proposes a field investigation of the maximum skew angle for fully integral bridges because of the inherently low stiffness associated with a single row of foundation piles. The study indicates that current VDOT guidelines can be relaxed to allow design of a wider range of jointless bridges. The implementation of integral design has been shown to reduce bridge lifetime costs because of the elimination of deck joints, which often create numerous maintenance problems.
Download or read book Measurement of the Abutment Forces of a Skewed Semi integral Bridge as a Result of Ambient Temperature Change written by Andrew T. Metzger and published by . This book was released on 1995 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Field Study of Integral Backwall with Elastic Inclusion written by Edward J. Hoppe and published by . This book was released on 2005 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: Jointless construction is considered an effective design option to reduce bridge maintenance costs and resist seismic loads. Although these attributes make the integral bridge an increasingly popular choice, soil-structure interaction issues unique to this type of design remain unresolved. Of particular concern is the excessive settlement of approach embankments, resulting from the repetitive, thermally induced cyclic movements of the superstructure. In many cases, rectifying this condition can be expensive because the integral bridge approach slab (if provided) cannot be overlaid with pavement. To address this soil-structure interaction problem, the Virginia Department of Transportation conducted a study designed to test the feasibility of using elastic inclusion at the integral backwall. The design was completed in mid-1997, and the bridge was opened to traffic in October 1999. The bridge was constructed with elasticized expanded polystyrene (EPS) attached to the backwall. The structure has been monitored continuously for 5 years. Significantly attenuated lateral earth pressures have been recorded at the backwall, and the settlement of the approach fill has been tolerable. Field data indicate that the elasticized EPS layer has been functioning effectively in allowing the superstructure to interact with the adjoining select backfill material. The use of elasticized EPS in conjunction with a well-compacted granular backfill offers a cost-effective way of minimizing settlements at bridge approaches.
Download or read book Effects of Thermal Expansion on a Skewed Semi integral Bridge written by Christopher L. Bettinger and published by . This book was released on 2001 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Forces Exerted in the Wingwalls of Skewed Semi integral Bridges written by Eric P. Steinberg and published by . This book was released on 2001 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the state of Ohio, semi-integral bridges have become more popular because these bridges eliminate high maintenance joints. The girders in a semi-integral bridge are encased in a diaphragm supported on elastomeric pads that bear on the abutment. Movement of the diaphragm caused by thermal change is theoretically resisted by backfill and also by the wingwalls for skewed bridges. The wingwalls are subjected to forces as a skewed bridge rotates during thermal expansion.
Download or read book Forces in Wingwalls from Thermal Expansion of Skewed Semi integral Bridges written by Eric P. Steinberg and published by . This book was released on 2010 with total page 87 pages. Available in PDF, EPUB and Kindle. Book excerpt: Jointless bridges, such as semi-integral and integral bridges, have become more popular in recent years because of their simplicity in the construction and the elimination of high costs related to joint maintenance. Prior research has shown that skewed semi-integral bridges tend to expand and rotate as the ambient air temperature increases through the season. As a result of the bridge movement, forces are generated and transferred to the wingwalls of the bridge. ODOT does not currently have a procedure to determine the forces generated in the wingwalls from the thermal expansion and rotation of skewed semi-integral bridges. In this study, two semi-integral bridges with skews were instrumented and monitored for behavior at the interface of the bridge's diaphragm and wingwall. A parametric analysis was also performed to determine the effects of different spans and bridge lengths on he magnitude of the forces. Based on the field results from the study it is recommended for the design of the wingwalls turned to run nearly parallel with the longitudinal axis of skewed semi-integral bridges should include a 100 psi loading at the wingwall/diaphragm interface from the thermal expansion of the bridge. In addition, analytical evaluations showed that longer spans and higher skews than allowed by ODOT's BDM could be used. However, additional considerations for larger movements and stresses generated at the wingwall/diaphragm interface would need to be considered in designs. Finally, bearing retainers in diaphragms, if used, require adequate cover to avoid spalling of concrete.
Download or read book LRFD Guide Specifications for the Design of Pedestrian Bridges written by American Association of State Highway and Transportation Officials and published by AASHTO. This book was released on 2009 with total page 38 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 Integral Bridges written by George L. England and published by Thomas Telford. This book was released on 2000 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work was commissioned by the Highways Agency to produce guidance for bridge designers by addressing the thermally induced soil/structure integration problem created by environmental changes of temperature and the associated cyclical displacements imposed on the granular backfill to the bridge abutments. It develops a better theoretical understanding of the cyclic performance, in particular the strain racheting in the backfill soil when in contact with a stiff structure. It also identifies the governing soil parameters and examines their influence in the interaction problem, develops numerical modelling procedures to predict interactive soil behaviour, and identifies and quantifies the controlling features of bridge structures relevant to the interaction problem.
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1987 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Design and Construction of Bridge Approaches written by Harvey E. Wahls and published by Transportation Research Board. This book was released on 1990 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: Includes case histories of the Dumbarton Bridge (San Francisco Bay, Calif.), the Rainier Avenue Embankment (Seattle, Wash.) and the Gallows Road Grade Separation (Fairfax, Va.)
Download or read book AASHTO Guide Specifications for LRFD Seismic Bridge Design written by and published by AASHTO. This book was released on 2011 with total page 271 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work offers guidance on bridge design for extreme events induced by human beings. This document provides the designer with information on the response of concrete bridge columns subjected to blast loads as well as blast-resistant design and detailing guidelines and analytical models of blast load distribution. The content of this guideline should be considered in situations where resisting blast loads is deemed warranted by the owner or designer.
Download or read book Guide Specifications for Seismic Isolation Design written by and published by AASHTO. This book was released on 2010 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: This edition is based on the work of NCHRP project 20-7, task 262 and updates the 2nd (1999) edition -- P. ix.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1971 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Internal Curing a 2010 State Of the Art Review written by nist and published by . This book was released on 2013-11-26 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: The American Concrete Institute in 2010 defined internal curing as supplying water throughout a freshly placed cementitious mixture using reservoirs, via pre-wetted lightweight aggregates, that readily release water as needed for hydration or to replace moisture lost through evaporation or self-desiccation (American Concrete Institute, 2010). While internal curing has been inadvertently included in many lightweight concretes produced within the past 100 years, it is only within the first decade of the 21st century that this technology has been intentionally incorporated into concrete mixtures at the proportioning stage, using a variety of materials including pre-wetted lightweight aggregates, pre-wetted crushed returned concrete fines, superabsorbent polymers, and pre-wetted wood fibers. This report provides a state-of-the-art review of the subject of internal curing, first addressing its history and theory, andthen proceeding to summarize published guidance on implementing internal curing in practice and published research on its influence on the performance properties of concrete. The ongoing exploration of extensions of the internal curing concept that employ the internal reservoirs to contain materials other than water are reviewed. Finally, the critical issue of sustainability is addressed. An extensive internal curing bibliography that is also available over the Internet is included in an appendix. The report is mainly focused on the utilization of prewettedlightweight aggregates as the internal reservoirs due to thisbeing the current established practice within the U.S.
Download or read book Crystal Plasticity Finite Element Methods written by Franz Roters and published by John Wiley & Sons. This book was released on 2011-08-04 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by the leading experts in computational materials science, this handy reference concisely reviews the most important aspects of plasticity modeling: constitutive laws, phase transformations, texture methods, continuum approaches and damage mechanisms. As a result, it provides the knowledge needed to avoid failures in critical systems udner mechanical load. With its various application examples to micro- and macrostructure mechanics, this is an invaluable resource for mechanical engineers as well as for researchers wanting to improve on this method and extend its outreach.
