Download or read book Localized Scour at Bridge Piers on Graded Particle Streambeds written by Howard D. Copp and published by . This book was released on 1991 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: This document reports on results of research to develop a method for estimating depth of local scour at bridge piers that would provide an improved estimate from current methodology, i.e., one (or more) based on sand bed streams.

Download or read book Scour at Bridge Piers written by R. Ettema and published by . This book was released on 1980 with total page 527 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Study of Local Scour Around Side by Side Bridge Piers Under Ice Covered Flow Conditions written by Jueyi Sui and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A precise prediction of maximum scour depth (MSD) around piers under ice-covered conditions is crucial for the safe design of the bridge foundation. Due to the lack of information for local scour under ice-covered flow condition, it is extremely hard to give proper estimation of MSD. In the current study, a set of flume experiments were completed to investigate local scour around four pairs of circular bridge piers with nonuniform bed materials under open channel, smooth and rough ice cover conditions. Three different bed materials with median particle size of 0.47, 0.50, and 0.58 mm were used to simulate natural river conditions. Regardless of pier size, the maximum scour depths were observed in front of the piers under all flow conditions. Additionally, a smaller pier size and a larger space between piers yield a smaller scour depth. Results showed that the maximum scour depth decreases with increase in the grain size of armor layer. The distribution of vertical velocity shows that the strength of downfall velocity is the greatest under rough ice cover. Empirical equations were developed to estimate the maximum scour depth around side-by-side bridge piers under both open-channel and ice-covered flow conditions.

Download or read book Evaluation of Bridge scour Data at Selected Sites in Ohio written by K. S. Jackson and published by . This book was released on 1996 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scour data collected during 1989-1994 were evaluated to determine whether pier scour and contraction scour occurred at 22 bridge sites in Ohio. Pier-scour depths computed from selected pier-scour prediction equations were compared with measured pier-scour depths, and the accuracy of the prediction equations were evaluated. Observed pier-scour relations were compared to similar relations developed through laboratory research. Mean streambed elevations were evaluated to determine the depth of contraction scour. Channel stability was assessed by use of mean streambed elevations at the approach section. Ground-penetrating radar was used at all sites to investigate the presence of historical scour.

Download or read book Local Scour Around Differently Shaped Bridge Piers An Experimental Investigation written by Kaleem Afzal and published by . This book was released on 2020-02-11 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bachelor Thesis from the year 2019 in the subject Physics - Mechanics, University of Engineering & Technology Peshawar, language: English, abstract: The objective of the study is to conduct laboratory model testing to investigate and compare scour hole depth of the diamond, square and elliptical scaled model of bridge piers in a cohesion less bedding material under clear water and to propose the most efficient cross section of the bridge pier, having less Local scour around piers under steady clear-water condition was studied experimentally for a variety of configuration, including different sizes and shapes of piers. Total number of forty experiments were performed in the flume using diamond, square and elliptical shape. The scouring around the square shape was found maximum and at elliptical shape was the least. The main reason was obstruction in flow area that was more in case of the square and less in case of the elliptical shape. However, the diamond shaped has the intermediate scouring under same condition. Local scour is a complex phenomenon involving three-dimensional flow, typically developed around piers founded in movable bed rivers. Local scour can lead to partial failure or to collapse of bridge piers because of the high flood velocity. The cost of large bridges, with common and special complex piers, justifies carrying out an accurate prediction of scour depth, for both economic and safety reasons, which in turn leads to the interest of hydraulic engineers in predicting the equilibrium scour depth.

Download or read book Scour at Bridge Piers written by Howard D. Copp and published by . This book was released on 1988 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Riverbed Scour at Bridge Piers written by Howard D. Copp and published by . This book was released on 1987 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scour at Bridge Sites in Delaware Maryland and Virginia written by Donald C. Hayes and published by . This book was released on 1996 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Debris on Bridge Pier Scour written by Peter Frederick Lagasse and published by Transportation Research Board. This book was released on 2010 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt: TRB's National Cooperative Highway Research Program (NCHRP) Report 653: Effects of Debris on Bridge Pier Scour explores guidelines to help estimate the quantity of accumulated, flow event debris, based on the density and type of woody vegetation and river bank condition upstream and analytical procedures to quantify the effects of resulting debris-induced scour on bridge piers. The debris photographic archive, the survey questionnaire and list of respondents, and the report on the field pilot study related to development of NCHRP 653 was published as NCHRP Web-Only Document 148: Debris Photographic Archive and Supplemental Materials for NCHRP Report 653.

Download or read book Pier and Contraction Scour in Cohesive Soils written by J.-L. Briaud and published by Transportation Research Board. This book was released on 2004 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Research sponsored by the American Association of State Highway and Transportation Officials in cooperation with the Federal Highway Administration."

Download or read book Local Scour at Bridge Sites written by B. W. Melville and published by . This book was released on 1975 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Pier Streamlining as a Bridge Local Scour Countermeasure and the Underlying Scour Mechanism written by Junhong Li and published by . This book was released on 2018 with total page 251 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bridge local scour has long been identified as the most critical cause to bridge failures. Countermeasures that are commonly used nowadays still have disadvantages to some extent. This work is among one of the ongoing efforts to explore reliable alternatives. Inspired by the streamlined body of boxfish and blue shark, this study introduced streamlining features to the bridge piers in order to reduce the erosive forces locally. Based on the excess shear stress criteria, the Reynolds-Averaged Navier Stokes (RANS) numerical model was employed to optimize the streamlined features through parametric studies. The maximum bed shear stress around the optimal streamlined pier was shown to be reduced by ~34% as compared to that around a non-streamlined pier. Further simulation using the advanced Detached Eddy Simulation (DES) model revealed that the streamlined pier also helped reduce the locally turbulence dynamics, which played a significant role in local scour. A set of small-scale flume tests were then conducted in the laboratory to characterize the flow physics and scour behavior of uniform Ottawa sand around piers with various streamlined extents. The experimental results further confirmed the effectiveness of pier streamlining in scour reduction. The maximum scour depth around the streamlined pier was reduced by ~66% as compared to that around a non-streamlined pier. Through monitoring the pore pressure response within sand, the role of vortex-induced excess pore pressure that plays in the scour mechanism was discussed. The vortex-induced excess pore pressure also helped to partially account for an interestingly counterintuitive observation from an independent experiment: the local scour resistance was a slightly decreasing function of the granular bulk density. Finally, a CFD-DEM (Discrete Element Model) two-way coupled model was established to simulate the scour behavior of uniform spherical particles around an oblong pier. The two-phase model successfully captured the characteristic local scour behaviors, and thus may serve as a platform of great potential to further investigate the scour mechanism at microscale in the future. Tremendous efforts were also made to review applications of the emerging two-phase numerical models to the broad flow-induced erosion problems.

Download or read book Mechanics of Local Scour written by S. S. Karaki and published by . This book was released on 1963 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Highway Research Abstracts written by and published by . This book was released on 1992 with total page 838 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Annual Index written by and published by . This book was released on 1992 with total page 1388 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sections 1-2. Keyword Index.--Section 3. Personal author index.--Section 4. Corporate author index.-- Section 5. Contract/grant number index, NTIS order/report number index 1-E.--Section 6. NTIS order/report number index F-Z.

Download or read book Local Scour at Bridge Piers in Nonuniform Sediment Under Dynamic Conditions written by David S. Mueller and published by . This book was released on 1996 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Local Scour Around Bridge Piers in Pressure Flow written by Laila M. Abed and published by . This book was released on 1991 with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt: