Download or read book Maximum Scour Depth at Bridge Abutments Terminating in the Floodplain Zone written by and published by . This book was released on 1997 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Most previous laboratory studies of local scour at bridge abutments were performed in rectangular channels in which the distributions of flow velocity and bed shear stress were considered uniform in the transverse direction. In reality, however, bridge abutments usually terminate in the flood plain zone of rivers where velocity and shear stress are not uniformly distributed. This paper presents the results of a laboratory study performed to investigate the impact of lateral momentum of flow intercepted by abutment and flow related to a specific channel width at the abutment end, is a significant parameter to account for lateral momentum transfer and should be incorporated in the scour prediction formulation. Also, based on the discharge ratio, Froude number, and critical Froude number associated with the sediment size, a relationship for predicting maximum local scour depth at bridge abutments was proposed.
Download or read book The Local Scouring Phenomenon at Bridge Abutments Terminating in the Floodplain Zone written by Salah Kouchakzadeh and published by . This book was released on 1996 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study examines the local scouring phenomenon associated with bridge abutments exposed to combined main-channel (MC) and floodplain (FP) flows. The principal goal of the study was to develop and validate, based on a comprehensive physical-model testing programme that considered different abutment shapes, an improved relationship for predicting maximum scour depth. A relationship was established among sediment size, flow depth and longitudinal channel slope for initiating the threshold condition of bed material movement. This relationship facilitated the selection of sediment size and channel bed slope for the various experiments, which were performed in a compound channel under interacting (combined MC and FP flows) and non-interacting (isolated FP flow) conditions. Clear-water approach-flow conditions were utilized throughout the testing programme. A flow visualization technique was employed to study the various patterns of the combining flows in the MC/FP junction regions. It determined both the flow deflection angle and the extent of the influence zone (a portion of the channel width beyond the abutment) whose discharge, $Q\sb{w}$, contributes to the scour development. Maximum scour depths produced under interacting conditions were observed to be 15% to 30% greater than those observed for non-interacting conditions. This important observation clearly demonstrated the need to properly account for compound-channel effects in the simulation exercise. The scour prediction relationship presented herein is based on a dimensional analysis of the relevant parameters and incorporates the data obtained from the laboratory studies performed in a compound channel using vertical-wall, wing-wall, semi-circular, and spill-through abutment shapes. The model indicates a very good agreement between predicted and observed maximum scour depths for bridge abutments terminating in the FP zone.
Download or read book Stream Stability and Scour at Highway Bridges written by Everett V. Richardson and published by ASCE Publications. This book was released on 1999-01-01 with total page 1076 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sponsored by the Water Resources Engineering (Hydraulics) Divsion of ASCE. This collection contains 75 papers and 321 abstracts presented at conferences sponsored by the Water Resources Engineering (Hydraulics) Division of ASCE from 1991 through 1998. The collection contains many new and expanded versions of the original papers and is designed to assist the practitioner with the concepts in evaluating stream instability and scour at bridges. Topics include: history of bridge scour research; bridge scour determination; stream stability and geomorphology; construction scour; instrumentation for measuring and monitoring; field measurement; computer and physical modeling of bridge scour; scour at culverts; and economic and risk analysis. One important paper contains 384 field measurements of local scour at piers made by the U.S. Geological Survey.
Download or read book Countermeasures to Protect Bridge Abutments from Scour written by Brian D. Barkdoll and published by Transportation Research Board. This book was released on 2007 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: Examines selection criteria and guidelines for the design and construction of countermeasures to protect bridge abutments and approach embankments from scour damage. The report explores two common forms of bridge abutments--wing-wall (vertical face with angled walls into the bank) and spill-through (angled face).
Download or read book Enhanced Abutment Scour Studies for Compound Channels written by Terry W. Sturm and published by DIANE Publishing. This book was released on 2004 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental results and analyses are given in this report on bridge abutment scour in compound channels. Experiments were conducted in a laboratory flume with a cross section consisting of a wide floodplain adjacent to a main channel. The embankment length, discharge, sediment size, and abutment shape were varied, and the resulting equilibrium scour depths were measured. Water-surface profiles, velocities, and scour-hole contours were also measured. In the report, a methodology is developed for estimating abutment scour that takes into account the redistribution of discharge in the bridge contraction, abutment shape, sediment size, and tailwater depth. The independant variables in the proposed scour formula are evaluated at the approach-channel cross section and can be obtained froma one-dimensional water-surface profile computer program such as the Water-Surface Profile Program (WSPRO). The proposed scour evaluation procedure is outlined and illustrated, including consideration of the time required to reach equilibrium scour. The proposed methodology is applied to two cases of measured scour in the field.
Download or read book Recent Trends in Civil Engineering written by K. K. Pathak and published by Springer Nature. This book was released on 2020-09-27 with total page 1081 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the selected peer-reviewed proceedings of the International Conference on Recent Trends and Innovations in Civil Engineering (ICRTICE 2019). The volume focuses on latest research and advances in the field of civil engineering and materials science such as design and development of new environmental materials, performance testing and verification of smart materials, performance analysis and simulation of steel structures, design and performance optimization of concrete structures, and building materials analysis. The book also covers studies in geotechnical engineering, hydraulic engineering, road and bridge engineering, building services design, engineering management, water resource engineering and renewable energy. The contents of this book will be useful for students, researchers and professionals working in civil engineering.
Download or read book Investigation of Flow and Local Scour Characteristics Around a Partially Submerged Permeable WSDOT Barb written by Athanasios Papanicolaou and published by . This book was released on 2004 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Local Scour at Bridge Abutments written by Deepak Man Singh Dongol and published by . This book was released on 1994 with total page 409 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Method for Rapid Estimation of Scour at Highway Bridges Based on Limited Site Data written by Steven R. Holnbeck and published by . This book was released on 1997 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comptes Rendus written by International Association for Hydraulic Research. Congress and published by . This book was released on 2001 with total page 998 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 2002 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluating Scour at Bridges written by E. V. Richardson and published by . This book was released on 1991 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: This document, Hydraulic Engineering Circular No. 18 (HEC-18), contains the state-of-knowledge and practice for dealing with scour at highway bridges. The procedures for designing new, replacement and rehabilitated bridges to resist scour are presented. Procedures are presented for evaluating the scour vulnerability of existing bridges as well as inspecting bridges for scour. The use of countermeasures to protect bridges evaluated as failure prone due to scour is also presented. This document replaces the Federal Highway Administration (FHWA) publication "Interim Procedures for Evaluating Scour at Bridges," which was issued with FHWA Technical Advisory 5140.20, "Scour at Bridges," in September 1988.
Download or read book Enhanced Abutment Scour Studies for Compound Channels written by U. S. Department Transportation and published by CreateSpace. This book was released on 2015-03-14 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental results and analyses are given in this report on bridge abutment scour in compound channels. Experiments were conducted in a laboratory flume with a cross section consisting of a wide floodplain adjacent to a main channel. The embankment length, discharge, sediment size, and abutment shape were varied, and the resulting equilibrium scour depths were measured. Water-surface profiles, velocities, and scour-hole contours were also measured. In the report, a methodology is developed for estimating abutment scour that takes into account the redistribution of discharge in the bridge contraction, abutment shape, sediment size, and tailwater depth. The independent variables in the proposed scour formula are evaluated at the approach-channel cross section and can be obtained from a one-dimensional water-surface profile computer program such as the Water-Surface Profile Program (WSPRO). The proposed scour evaluation procedure is outlined and illustrated, including consideration of the time required to reach equilibrium scour. The proposed methodology is applied to two cases of measured scour in the field. Research objectives include: Investigate the effects of flow distribution, as affected by abutment length, on clear-water abutment scour in a compound channel for abutment lengths that terminate on the floodplain as well as encroach on the bank of the main channel. Quantify the effects of floodplain sediment size on abutment scour. Explore the influence of abutment shapes, including wingwall, vertical-wall, and spill-through shapes, on equilibrium scour-hole depth and scour-hole form. Determine the relative importance of the live-bed scour case compared to the clear-water case when there is sediment transport in the main channel and the abutment encroaches on the main channel. Combine the experimental results into a methodology for assessing field abutment scour and test it on available field data.
Download or read book Dissertation Abstracts International written by and published by . This book was released on 1997 with total page 876 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Potential scour Assessments and Estimates of Maximum Scour at Selected Bridges in Iowa written by Edward E. Fischer and published by . This book was released on 1995 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bridge Scour written by Bruce W. Melville and published by Water Resources Publication. This book was released on 2000 with total page 586 pages. Available in PDF, EPUB and Kindle. Book excerpt: "A comprehensive state-of-the-art treatment of scour and bridge foundations - both a handy reference text and a manual for the practicing bridge designer."--Publisher.
Download or read book International Journal of Sediment Research written by and published by . This book was released on 2002 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt:
