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 Local Scour Around Bridge Abutments Under Ice Covered Conditions written by Peng Wu and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Local scour refers to the sediment transport around hydraulic structures by flowing water. Excessive scour around the abutment can potentially cause damage to the bridge, which may also result in catastrophic consequences. Abutment scour refers to the local scour generated by the flow passing around bridge abutments. One of the challenging problems for hydraulic engineers is the prediction of maximum scour depth around abutments and pier foundations so that proper provisions can be made in the design and construction to mitigate the consequences. Despite significant research efforts to improve the understanding of scour related problems, abutment scour is still among the more complex and challenging problems. Over the past few decades, local scour around bridge abutments has received wide attention, and many researchers have contributed various studies on the topic. The current state knowledge on local scour still has insufficiently understood aspects, for example, ice accumulation has never been addressed in the abutment scour research. The impacts of ice cover has never been conducted. To fill this gap, the present research is conducted. The ice cover can change the channel morphology and flow field. It is well known that river ice affects the vertical and lateral distribution of flow in a channel. Additionally, because river ice affects the flow conditions, it potentially influence sediment transport. Hence, the scour around abutments is affected. In the present research, a series of large flume experiments are conducted. By adding different simulated ice covers in the flume, ice-covered flow can be generated. By comparing the scour profiles and maximum scour depth around two commonly used abutments in three non-uniform sediments, the ice cover impacts have been investigated. A significant increase can be noticed by adding ice cover. With the increase in ice cover roughness, the maximum scour depth increase correspondingly. Meanwhile, semi-circular abutment can generate a relatively small scour hole. Further.
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 Bridge Hydraulics written by Dr Les Hamill and published by CRC Press. This book was released on 1998-12-03 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: The design of bridges across rivers and streams is a major component of many civil engineering projects. The size of waterways must be kept reasonably small for reasons of economy and yet be large enough to allow floods to pass. Bridge Hydraulics is the first book to consider both arched and rectangular waterway openings in detail and to describe a
Download or read book Time Dependent Local Scour Around Groynes And Bridge Abutments written by Uzzwal Kumar Deb Nath and published by LAP Lambert Academic Publishing. This book was released on 2013 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scour around any obstruction is the lowering of a portion of the river bed below its natural level. This is caused due to the large scale eddies or a system of vortices which are developed near the obstruction. Local scour occurs around abutments, spur dikes and embankments because of the obstruction to flow caused by such structures. Though the mechanism of scour is difficult to quantify but its study gives considerable guidance in predicting the magnitude of scour around any hydraulic structure. The determination of scour depth is required for the design of any foundation of hydraulic structure for its safety as the development of scour hole is one of the principal causes of failure of any hydraulic structure. A number of scour depth prediction formulae available so far have been analyzed in order to find out appropriate scour predictor around such structures in Bangladesh. By this study it has been tried to evaluate scour development around groynes and bridge abutments from both laboratory and field data and to evaluate recent methods for calculating equilibrium scour and time dependent scour.
Download or read book Experimental and Numerical Study of Local Scour Around Side by side Bridge Piers Under Ice covered Conditions written by Mohammad Reza Namaee and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Local scour around piers and abutments is one of the main causes of the collapse of many bridges constructed inside rivers. Many researchers have conducted various studies to predict the maximum depth of a scour hole around bridge piers and abutments. However, most of them have been done in small-scale laboratory flumes and specifically for the open channel condition. Besides, most of the existing research on bridge piers uses uniform sediment which is not an appropriate representative of natural river systems. This can result in excessively conservative design values for scour in low risk or non-critical hydrologic conditions. The most severe cases of bridge pier scouring occur in cold regions when the surface of water turns into ice in which, an additional boundary layer is being added to the water surface, which leads to significant changes in the flow field and scour pattern around bridge piers. Ice cover also causes the maximum flow velocity to move closer to the channel bed.
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 152 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 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 Local Scour at Bridge Abutments written by C. B. Tey and published by . This book was released on 1984 with total page 111 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 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 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 CIGOS 2021 Emerging Technologies and Applications for Green Infrastructure written by Cuong Ha-Minh and published by Springer Nature. This book was released on 2021-10-28 with total page 1861 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book highlights the key role of green infrastructure (GI) in providing natural and ecosystem solutions, helping alleviate many of the environmental, social, and economic problems caused by rapid urbanization. The book gathers the emerging technologies and applications in various disciplines involving geotechnics, civil engineering, and structures, which are presented in numerous high-quality papers by worldwide researchers, practitioners, policymakers, and entrepreneurs at the 6th CIGOS event, 2021. Moreover, by sharing knowledge and experiences around emerging GI technologies and policy issues, the book aims at encouraging adoption of GI technologies as well as building capacity for implementing GI practices at all scales. This book is useful for researchers and professionals in designing, building, and managing sustainable buildings and infrastructure.
Download or read book Scour Manual written by G.J.C.M. Hoffmans and published by CRC Press. This book was released on 2021-03-08 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ever since the publication in 1997 the original Scour Manual has helped many practising hydraulic engineers to deal with scour processes near hydraulic structures. In recent years new insights, such as probabilistic calculations, offered new opportunities to design structures more economically. These new insights are included in this update of the original Scour Manual, which is focussing entirely on current-related scour. This manual provides the engineer with useful practical methods to calculate the dimensions of scour holes in the pre-feasibility and preliminary stages of a project, and gives an introduction to the most relevant literature. This updated Scour Manual contains guidelines that can be used to solve problems related to scour in engineering practice and also reflects the main results of all research projects in the Netherlands in recent decades. The so-called Breusers equilibrium method has a central role, which can basically be applied to all situations where local scour is expected. The method allows to predict the scour depth as a function of time, provided that the available knowledge about scour at the specific structure is sufficient. For structures with insufficient knowledge available, alternative scour prediction rules are presented. The treatment of local scour is classified according to the different types of structures. Each type of structure is necessarily schematised to a simple, basic layout. The main parameters of a structure and the main parts of the flow pattern near a structure are described briefly insofar they are relevant to the description of scour phenomena. New scour formulas for the equilibrium scour have been elucidated. Evaluating a balance of forces for a control volume, it is possible to develop scour equations for different types of flow fields and structures, i.e. jets, abutments and bridge piers. As many scour problems are still not fully understood, attention is paid to the validity ranges and limitations of the formulas, as well as to the accuracy of the scour predictions. This information can also be used to carry out a risk assessment using a safety philosophy based on a probabilistic analysis or an approach with a safety factor. Moreover, the information on the strength of soils is extended and aspects are addressed such as scour due to shear failures or flow slides, that can progressively damage the bed protection which might lead to the failure of hydraulic structures. This updated Scour Manual presents scour prediction methods and deals with practically related scour problems. Consultants and contractors were invited to provide case studies of realized projects, including the methods that were followed. These case studies will help with grasping the concept of scour by the flow of water. This manual provides the engineer with the latest knowledge and with case studies that show how to apply the formulas and their limitations.
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 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 The Mechanics of Scour in the Marine Environment written by B. Mutlu Sumer and published by World Scientific. This book was released on 2002 with total page 558 pages. Available in PDF, EPUB and Kindle. Book excerpt: Treats the subject of local sour around different kinds of marine structures, exposed to waves and/or currents.
