Download or read book Large scale Testing of Passive Force Behavior for Skewed Bridge Abutments with Gravel and Geosynthetic Reinforced Soil GRS Backfills written by Amy Fredrickson and published by . This book was released on 2015 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: Test results in both sets of backfills confirmed previous findings that there is significant reduction in passive force with skewed abutment configurations. The reduction factor was 0.58 for the gravel backfill and 0.63 for the GRS backfill, compared to the predicted reduction factor of 0.53 for a 30° skew. These results are within the scatter of previous skewed testing, but could indicate that slightly higher reduction factors may be applicable for gravel backfills.
Download or read book Large scale Testing of Passive Force Behavior for Skewed Abutments with High Width height Ratios written by Katie Noel Palmer and published by . This book was released on 2013 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effects of seismic forces and thermal expansion on bridge performance necessitate an accurate understanding of the relationship between passive force and backwall deflection. In past case studies, skewed bridges exhibited significantly more damage than non-skewed bridges. These findings prompted studies involving numerical modeling, lab-scales tests, and large-scale tests that each showed a dramatic reduction in passive force with increased skew. Using these results, a correlation was developed between peak passive force and backwall skew angle. The majority of these tests had length to height ratios of 2.0; however, for several abutments in the field, the length to height ratio might be considerably higher than 2.0. This change in geometry could potentially affect the validity of the previously found passive force reduction correlation.
Download or read book Evaluation of Passive Force on Skewed Bridge Abutments with Large scale Tests written by Aaron Kirt Marsh and published by . This book was released on 2013 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accounting for seismic forces and thermal expansion in bridge design requires an accurate passive force versus backwall deflection relationship. Current design codes make no allowances for skew effects on the development of the passive force. However, small-scale experimental results and available numerical models indicate that there is a significant reduction in peak passive force as skew angle increases for plane-strain cases. To further explore this issue large-scale field tests were conducted at skew angles of 0°, 15°, and 30° with unconfined backfill geometry. The abutment backwall was 11 feet (3.35-m) wide by 5.5 feet (1.68-m) high, and backfill material consisted of dense compacted sand. The peak passive force for the 15° and 30° tests was found to be 73% and 58%, respectively, of the peak passive force for the 0° test which is in good agreement with the small-scale laboratory tests and numerical model results. However, the small differences may suggest that backfill properties (e.g. geometry and density) may have some slight effect on the reduction in peak passive force with respect to skew angle. Longitudinal displacement of the backfill at the peak passive force was found to be approximately 3% of the backfill height for all field tests and is consistent with previously reported values for large-scale passive force-deflection tests, though skew angle may slightly reduce the deflection necessary to reach backfill failure. The backfill failure mechanism appears to transition from a log spiral type failure mechanism where Prandtl and Rankine failure zones develop at low skew angles, to a failure mechanism where a Prandtl failure zone does not develop as skew angle increases.
Download or read book Passive Force deflection Behavior for Abutments with MSE Confined Approach Fills written by Kyle M. Rollins and published by . This book was released on 2010 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: Approach fills behind bridge abutments are commonly supported by wrap-around mechanically stabilized earth (MSE) walls; however the effect of this geometry on passive force development is unknown. This report describes the first large-scale tests to evaluate passive force-deflection curves for abutments with MSE wingwalls. A test was also performed with fill extending beyond the edge of the abutment wall for comparison. The abutment wall was simulated with a pile supported cap 5.5 ft high, 11 ft wide, and 15 ft long in the direction of loading. The backfill behind the pile cap consisted of clean sand compacted to 96% of the modified Proctor maximum density. As the pile cap was loaded laterally, pressure on the MSE wall led to pull-out of the steel reinforcing grids and the MSE wall panels moved outward about 2% of the wall height when the ultimate passive force developed. Despite pullout, the passive force per effective width was 28 kips/ft for the pile cap with MSE wingwalls compared to 22.5 kips/ft for the cap without wingwalls. Nevertheless, the passive force with the MSE wingwalls was still only 76% of the resistance provided by the cap with fill extending beyond the edges. The pile cap with MSE walls required greater movement to reach the ultimate passive force (deflection of 4.2% of wall height vs. 3%). The Caltrans method provided good agreement with the measured passive resistance while the log spiral method required the use of a higher plane strain friction angle to provide reasonable agreement.
Download or read book Skew Effects on Passive Earth Pressures Based on Large scale Tests written by Shon Joseph Jessee and published by . This book was released on 2012 with total page 77 pages. Available in PDF, EPUB and Kindle. Book excerpt: The passive force-deflection relationship for abutment walls is important for bridges subjected to thermal expansion and seismic forces, but no test results have been available for skewed abutments. To determine the influence of skew angle on the development of passive force, lab tests were performed on a wall with skew angles of 0o, 15o, 30o, and 45o. The wall was 1.26 m wide and 0.61 m high and the backfill consisted of dense compacted sand. As the skew angle increased, the passive force decreased substantially with a reduction of 50% at a skew of 30o. An adjustment factor was developed to account for the reduced capacity as a function of skew angle. The shape of the passive force-deflection curve leading to the peak force transitioned from a hyperbolic shape to a more bilinear shape as the skew angle increased. However, the horizontal displacement necessary to develop the peak passive force was typically 2 to 3.5% of the wall height. In all cases, the passive force decreased after the peak value, which would be expected for dense sand; however, at higher skew angles the drop in resistance was more abrupt than at lower skew angles. The residual passive force was typically about 35 to 45% lower relative to the peak force. Lateral movement was minimal due to shear resistance which typically exceeded the applied shear force. Computer models based on the log-spiral method, with apparent cohesion for matric suction, were able to match the measured force for the no skew case as well as the force for skewed cases when the proposed adjustment factor was used.
Download or read book Mini Pier Testing To Estimate Performance of Full Scale Geosynthetic Reinforced Soil Bridge Abutments written by Michael T. Adams and published by . This book was released on 2014 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: The geosynthetic reinforced soil (GRS) performance test (PT), also called a mini-pier experiment, was developed by the Federal Highway Administration (FHWA) to evaluate the material strength properties of GRS composites built with a unique combination of reinforcement, compacted fill, and facing elements. The PT consists of constructing a 1.4-m square column of alternating layers of compacted granular fill and geosynthetic reinforcement with a facing element that is frictionally connected up to a height of 2 m, then axially loading the GRS mass while measuring deformation to monitor performance. The results can be directly used in the design of GRS abutments and integrated bridge systems. Considering that the geometry of the PT is square in plan, the equivalency of the results to a bridge application, which more resembles a plane strain condition, is evaluated and presented in this paper. The analysis indicates that the PT closely approximates the bearing resistance, or capacity, of a typical GRS abutment, and is a conservative estimate when predicting stiffness. These results indicate that the PT can be used as a design tool for GRS abutments at both the strength and service limit states.
Download or read book Numerical Analysis of Passive Force on Skewed Bridge Abutments written by Zifan Guo and published by . This book was released on 2015 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: The results were particularly sensitive to the soil friction angle, wall friction angle, angle of dilatancy, soil stiffness and lateral restraint of the abutment backwall movement.
Download or read book Dynamic Passive Pressure on Abutments and Pile Caps written by and published by . This book was released on 2010 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geosynthetic Reinforced Soil GRS Walls written by Jonathan T. H. Wu and published by John Wiley & Sons. This book was released on 2019-07-10 with total page 414 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first book to provide a detailed overview of Geosynthetic Reinforced Soil Walls Geosynthetic Reinforced Soil (GRS) Walls deploy horizontal layers of closely spaced tensile inclusion in the fill material to achieve stability of a soil mass. GRS walls are more adaptable to different environmental conditions, more economical, and offer high performance in a wide range of transportation infrastructure applications. This book addresses both GRS and GMSE, with a much stronger emphasis on the former. For completeness, it begins with a review of shear strength of soils and classical earth pressure theories. It then goes on to examine the use of geosynthetics as reinforcement, and followed by the load-deformation behavior of GRS mass as a soil-geosynthetic composite, reinforcing mechanisms of GRS, and GRS walls with different types of facing. Finally, the book finishes by covering design concepts with design examples for different loading and geometric conditions, and the construction of GRS walls, including typical construction procedures and general construction guidelines. The number of GRS walls and abutments built to date is relatively low due to lack of understanding of GRS. While failure rate of GMSE has been estimated to be around 5%, failure of GRS has been found to be practically nil, with studies suggesting many advantages, including a smaller susceptibility to long-term creep and stronger resistance to seismic loads when well-compacted granular fill is employed. Geosynthetic Reinforced Soil (GRS) Walls will serve as an excellent guide or reference for wall projects such as transportation infrastructure—including roadways, bridges, retaining walls, and earth slopes—that are in dire need of repair and replacement in the U.S. and abroad. Covers both GRS and GMSE (MSE with geosynthetics as reinforcement); with much greater emphasis on GRS walls Showcases reinforcing mechanisms, engineering behavior, and design concepts of GRS and includes many step-by-step design examples Features information on typical construction procedures and general construction guidelines Includes hundreds of line drawings and photos Geosynthetic Reinforced Soil (GRS) Walls is an important book for practicing geotechnical engineers and structural engineers, as well as for advanced students of civil, structural, and geotechnical engineering.
Download or read book Constitutive Modeling of Geomaterials written by Teruo Nakai and published by CRC Press. This book was released on 2012-07-23 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: Winner of the Japanese Geotechnical Society 2016 publication awardWritten by a veteran geotechnical engineer with a long record of research discoveries, Constitutive Modeling of Geomaterials: Principles and Applications presents a simple and unified approach to modeling various features of geomaterials in general stress systems. The book
Download or read book Soil Improvement and Ground Modification Methods written by Peter G. Nicholson and published by Butterworth-Heinemann. This book was released on 2014-08-29 with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by an author with more than 25 years of field and academic experience, Soil Improvement and Ground Modification Methods explains ground improvement technologies for converting marginal soil into soil that will support all types of structures. Soil improvement is the alteration of any property of a soil to improve its engineering performance. Some sort of soil improvement must happen on every construction site. This combined with rapid urbanization and the industrial growth presents a huge dilemma to providing a solid structure at a competitive price. The perfect guide for new or practicing engineers, this reference covers projects involving soil stabilization and soil admixtures, including utilization of industrial waste and by-products, commercially available soil admixtures, conventional soil improvement techniques, and state-of-the-art testing methods. - Conventional soil improvement techniques and state-of-the-art testing methods - Methods for mitigating or removing the risk of liquefaction in the event of major vibrations - Structural elements for stabilization of new or existing construction industrial waste/by-products, commercially available soil - Innovative techniques for drainage, filtration, dewatering, stabilization of waste, and contaminant control and removal
Download or read book Hydraulic Structures written by P. Novak and published by CRC Press. This book was released on 2017-12-21 with total page 736 pages. Available in PDF, EPUB and Kindle. Book excerpt: Now includes Worked Examples for lectutrers in a companion pdf! The fourth edition of this volume presents design principles and practical guidance for key hydraulic structures. Fully revised and updated, this new edition contains enhanced texts and sections on: environmental issues and the World Commission on Dams partially saturated soils, small amenity dams, tailing dams, upstream dam face protection and the rehabilitation of embankment dams RCC dams and the upgrading of masonry and concrete dams flow over stepped spillways and scour in plunge pools cavitation, aeration and vibration of gates risk analysis and contingency planning in dam safety small hydroelectric power development and tidal and wave power wave statistics, pipeline stability, wave–structure interaction and coastal modelling computational models in hydraulic engineering. The book's key topics are explored in two parts - dam engineering and other hydraulic structures – and the text concludes with a chapter on models in hydraulic engineering. Worked numerical examples supplement the main text and extensive lists of references conclude each chapter. Hydraulic Structures provides advanced students with a solid foundation in the subject and is a useful reference source for researchers, designers and other professionals.
Download or read book IFCEE 2015 written by Magued Iskander and published by . This book was released on 2015 with total page 2845 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bridge Engineering Handbook written by Wai-Fah Chen and published by CRC Press. This book was released on 2019-09-11 with total page 690 pages. Available in PDF, EPUB and Kindle. Book excerpt: First Published in 1999: The Bridge Engineering Handbook is a unique, comprehensive, and state-of-the-art reference work and resource book covering the major areas of bridge engineering with the theme "bridge to the 21st century."
Download or read book Settlement of Bridge Approaches written by J.-L. Briaud and published by . This book was released on 1997 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: This synthesis will be of interest to state Departments of Transportation (DOTs) geotechnical, structural, roadway design, construction, and maintenance engineers; DOT research staff; and personnel in local transportation agencies. This synthesis describes the current state of the practice for the design, construction, and maintenance of bridge approaches to reduce, eliminate, or compensate for settlement at the bridge/abutment/embankment interface or the bump at the end of the bridge. It discusses the geotechnical and structural engineering design and procedural factors to reduce the bump at the end of the bridge, and includes numerous illustrations. This report of the Transportation Research Board presents data obtained from a review of the literature and a survey of the state DOTs. It is a supplemental update to Synthesis of Highway Practice 159: Design and Construction of Bridge Approaches (1990). The synthesis identifies and describes techniques that have been used to alleviate the problem of the bump at the end of the bridge including the location and cause of settlement and methods used to reduce settlement. In addition, the types of interaction between various divisions of the DOTs in the design, construction, and maintenance of bridge approaches are addressed.
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 Bridge Life cycle Cost Analysis written by Hugh Hawk and published by Transportation Research Board. This book was released on 2003 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accompanying CD-ROM contains software, Guidance manual, User manual, and appendixes to report.
