Download or read book Measurement of Scour depth Near Bridge Piers written by John V. Skinner and published by . This book was released on 1986 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Instrumentation for Measuring Scour at Bridge Piers and Abutments written by Peter Frederick Lagasse and published by Transportation Research Board. This book was released on 1997 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This report contains the findings of a study undertaken to develop, test, and evaluate fixed devices for measuring maximum scour depth. Companion manuals provide specific fabrication, installation, and operation guidance for two such devices. This report and the companion manuals will be of immediate interest to hydraulics engineers, bridge management engineers, and bridge maintenance engineers"--Foreward.

Download or read book Local Scour Around Differently Shaped Bridge Piers An Experimental Investigation written by Kaleem Afzal and published by GRIN Verlag. This book was released on 2020-02-06 with total page 55 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 Instrumentation for Measuring Scour at Bridge Piers and Abutments Main report written by and published by . This book was released on 1991 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation of Pier scour Equations for Coarse bed Streams written by Katherine J. Chase and published by . This book was released on 2004 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Streambed scour at bridge piers is among the leading causes of bridge failure in the United States. Several pier-scour equations have been developed to calculate potential scour depths at existing and proposed bridges. Because many pier-scour equations are based on data from laboratory flumes and from cohesionless silt- and sand-bottomed streams, they tend to overestimate scour for piers in coarse-bed materials. Several equations have been developed to incorporate the mitigating effects of large particle sizes on pier scour, but further investigations are needed to evaluate how accurately pier-scour depths calculated by these equations match measured field data. This report, prepared in cooperation with the Montana Department of Transportation, describes the evaluation of five pier-scour equations for coarse-bed streams. Pier-scour and associated bridge-geometry, bed-material, and streamflow measurement data at bridges over coarse-bed streams in Montana, Alaska, Maryland, Ohio, and Virginia were selected from the Bridge Scour Data Management System. Pier scour calculated using the Simplified Chinese equation, the Froehlich equation, the Froehlich design equation, the HEC-18/Jones equation and the HEC-18/Mueller equation for flood events with approximate recurrence intervals of less than 2 to 100 years were compared to 42 pier-scour measurements. Comparison of results showed that pier-scour depths calculated with the HEC-18/Mueller equation were seldom smaller than measured pier-scour depths. In addition, pier-scour depths calculated using the HEC-18/Mueller equation were closer to measured scour than for the other equations that did not underestimate pier scour. However, more data are needed from coarse-bed streams and from less frequent flood events to further evaluate pier-scour equations.

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 102 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 Scour Around Bridge Piers written by Gordon Ray Hopkins and published by . This book was released on 1980 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Available theories and prediction formulas on scour at bridge waterways are reviewed. Formulas that offer potential for prediction of scour around bridge piers are compared by reducing each formula to a non-dimensional form that includes Froude Number, the ratio of scour depth to pier width, and the ratio of stage to pier width. A field study to gather data on scour and related variables is described. The study is aimed at collecting field data in order to furnish a basis on which to compare scour prediction formulas.

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 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 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 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 Scour and Erosion written by Susan Burns and published by . This book was released on 2014 with total page 1152 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Instrumentation for Measuring Scour at Bridge Piers and Abutments Appendices written by and published by . This book was released on 1992 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design Relationships for Maximum Local Scour Depth for Bridge Pier Groups written by Mehrdad Nazariha and published by . This book was released on 1996 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: An investigation of local scour at pier groups has been conducted with the aim of developing design recommendations and scour depth prediction equations for the bridge pier groups. A comprehensive series of steady uniform flow experiments was performed on groups of 2, 3, 4, and 6 model piers. All tests were conducted under clear-water scour conditions. Parameters governing local scour depth around bridge piers include: flow characteristics, sediment properties, and pier size and shape. The effects of these parameters on the maximum local scour depth for a single pier (D$\sb{\rm s}$), have been thoroughly investigated in the past. However, when design criteria developed for single piers are applied directly to pier groups, this approach ignores the following important group effects: (1) sheltering, (2) reinforcement, and (3) horse-shoe vortex (HSV) compression. Furthermore, the group effects will alter with changes in pier spacing, S, and flow angle of attack, $\beta$. This study, which investigates the local scouring process for the aforementioned groups of model bridge piers, and presents design relationships for predicting the corresponding maximum local scour depths, is an attempt to address this limitation in current design practice. Initially the local scour was examined for five different single pier diameters (0.0127 m, 0.018 m, 0.025 m, 0.033 m and 0.05 m). Having established single pier relationships, groups of 2, 3, 4, and 6 equally spaced piers were examined, while altering alignment to the flow and separation distances. For piers in line with the flow direction, downstream piers are sheltered by the upstream ones resulting in reducing scour depth around downstream piers. This effect diminishes with the increasing $\beta$ if there is only one row of piers i.e., 2 and 3 pier groups. In the case of 2 rows of piers aligned to the flow direction (i.e., 4- and 6-pier groups), there is a specific range of $\beta$ in which downstream piers are exposed to the flow. As $\beta$ increases, depending on pier spacing, the piers of one row may shelter the downstream piers of the other row. The reinforcement effect is significant only for small ratios of pier spacing/ pier diameter (S/d) when $\beta \le$ 10$\sp0$. In these ranges of S/d and $\beta$, the front piers are scoured more than that of a single pier. Moreover, the score depth of downstream piers, which are less than that of a single pier, increases with increasing S/d. The compressed (HSV) arms affect the local scour depth significantly if piers are staggered and S/d $\le$ 5. In this range of S/d, the HSV arms are intensified, resulting in a deeper scour hole. However, this effect also becomes insignificant with increasing S/d. The data obtained for each pier group were analysed, using a multiple regression model, to develop local scour depth prediction equations for the front, middle, and rear piers. The regression model includes two important dimensionless parameters ($\beta$ and S/d) associated with group effects, as regressors. The proposed prediction equations estimated the observed data and similar-type published data reasonably well, within marginal errors. From a general practical view-point, the number of prediction equations was reduced to two equations for all pier groups: one for the front piers and the second one for the downstream piers (i.e. combined middle and rear piers).

Download or read book Field Measurement of Scour Around Bridge Piers Waimakariri River written by Alexander James Sutherland and published by . This book was released on 1982 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reports on field tests of "Scubamouse", a sensing device used for a method of measuring scour depth during a flood.

Download or read book Scouring written by H.N.C. Breusers and published by CRC Press. This book was released on 2020-08-13 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: Information and technical data concerning scouring/erosion caused by water fl in rivers and streams. More specifically, how certain structures exaggerate this natural process by restricting water flow, causing constriction and loc scour. Material presented is from both field studies and laboratories

Download or read book Measurement of Bridge Scour at Selected Sites in New York Excluding Long Island written by Gerard K. Butch and published by . This book was released on 1991 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: