Download or read book Developing a Bridge Scour Warning System written by C. Bryan Young and published by . This book was released on 2016 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: Flooding and scour can be major threats to the integrity of bridges. During flood events, scour at bridge piers and abutments can undermine the foundations of the bridge, causing significant damage or even total structure loss. Because scour occurs below the water level during a large flood event, it can be difficult to detect and may go unnoticed unless a targeted inspection is performed. The Kansas Department of Transportation (KDOT) is required by federal mandate to establish and maintain a bridge scour plan of action for all scour-critical bridges in the state. A plan of action can include the implementation of scour countermeasures to protect and stabilize a bridge and/or scour monitoring. Bridge scour monitoring presents multiple challenges for bridge owners, including state Departments of Transportation (DOTs). This research project surveyed in situ and ex situ monitoring options with particular attention on warning system options in the public domain. In situ monitoring can include portable and/or fixed devices for detecting bridge scour. Ex situ monitoring implies a statewide system that issues scour alerts to trigger bridge closures and/or inspections based on hydrologic conditions (rainfall and/or streamflow). A systematic statewide system would be preferable for monitoring scour-capable events at bridges across the state. KDOT could leverage existing United States Geological Survey (USGS) and National Weather Service (NWS) tools to monitor scour-critical bridges or pursue a vendor to offer a turn-key solution. For critical locations, additional measures could be implemented at specific sites to offer more information or a higher level of monitoring.
Download or read book Sensor Development and Response Analysis for Bridge Scour Monitoring and Prognosis written by Faezeh Azhari and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Bridges, as well as off-shore wind turbines and other marine structures, are susceptible to failures due to local scour, which is a dynamic phenomenon that is caused by flowing water removing the bed material from around piles, piers, and abutments. If extended over a critical depth, scour can jeopardize the stability and safety of overwater bridges. In fact, scour is the predominant cause of overwater bridge failures in North America and around the world. Monitoring, as part of bridge maintenance, can prevent scour-induced damage and failure by continuously measuring the extent of scour so that preventative measures can be taken in a timely manner. Over the years, numerous sensing systems have been developed for monitoring bridge scour by measuring scour depth at locations near bridge piers and abutments. Due to the limitations of periodic inspections conducted by trained divers and by using portable instruments, fixed monitoring systems have become the viable solution. Existing fixed scour sensors include sonar systems, float-out devices, and tilt meters, to name a few. These systems each offer unique advantages, but have limitations (e.g., high costs, low reliability, limited accuracy, etc.) that have restricted their implementation in practice. Therefore, attempts to develop more efficient monitoring schemes continue. In this study two novel scour sensing schemes were evaluated. The first uses driven piezoelectric rods to continuously measure scour depth; and in the second, buried dissolved oxygen (DO) optodes detect scour at discrete depths. Laboratory flume experiments were conducted to validate the proposed sensing systems. In the first sensing scheme, piezoelectric rods are driven into the stream bed at a location where scour depths are wanted. As the scour hole extends, the exposed length of the rod changes, causing the flow-induced voltage signal acquired from the sensor to also vary. Scour depth at the sensor location is determined based on the fact that the natural frequency of the cantilevered sensing rod is inversely related to its length. Prototype piezoelectric rods, in which a poly(vinylidene fluoride) (PVDF) polymer strip forms the main sensing component, were designed and developed. Following various preliminary validation tests, extensive laboratory experiments were performed in which the in-house piezoelectric sensing rods were driven into the soil surrounding a mock bridge pier inside a flume simulating scour conditions. The piezo-sensor was calibrated through eigenfrequency analyses. The second sensing system utilized commercially available miniature DO probes. DO levels are very low in streambed sediments, as compared to the standard level of oxygen in flowing water. Therefore, scour depths can be determined by installing sensors to monitor DO levels at various depths along the buried length of a bridge pier or abutment. The measured DO is negligible when a sensor is buried but would increase significantly once scour occurs and exposes the sensor to flowing water. A set of experiments was conducted in which four dissolved oxygen probes were embedded at different soil depths in the vicinity of a mock bridge pier inside a laboratory flume simulating scour conditions. The measured DO jumped to water DO levels once scour exposed the sensing tip of the probes to flowing water, thereby providing discrete measurements of the maximum scour depth. The sensing concepts behind both scour monitoring schemes were confirmed through comparing the detected and observed scour depths. The PVDF-based sensors provide continuous scour depth measurements, as opposed to discrete ones offered by the DO sensing system. Both sensing schemes were also able to detect any subsequent refilling of the scour hole through the deposition of sediments. Following separate analyses of the results, future research is suggested for the two sensing techniques to gain a better understanding of their advantages, shortcomings, and potential applications. In addition to developing and validating the aforementioned scour sensing schemes, research was conducted aimed at creating a practical warning-time based framework for scour sensor response interpretation. First, the general form of the framework, applicable to a wide range of damage detection operations, was developed. The purpose of structural health monitoring (SHM) is to diagnose any damage or malfunction in an engineering system in a timely manner. Timely detection implies that sufficient warning time is given to perform required maintenance to prevent structural failure. Warning time information is therefore very useful in the design and planning of maintenance procedures. The framework developed as part of this research, is a simple and practical tool for predicting warning times given detected damage (i.e. sensor outputs). The framework incorporates a probabilistic analysis of damage progression such that the uncertainty in warning times can also be determined and used for risk-based decision making. To demonstrate the framework’s applicability to scour monitoring, a detailed example was considered, where the progression of bridge scour was obtained through computational fluid dynamics (CFD) simulations using the software Flow-3D. The resulting diagrams from the framework can be used as an effective tool in estimating the warning time and the uncertainty in the warning time given a detected scour depth. The warning information is extremely useful in identifying and planning the required maintenance procedures based on the available resources.
Download or read book Development of an Innovative Bridge Scour Monitoring System written by 陳俊仲 and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stream Instability Bridge Scour and Countermeasures A Field Guide for Bridge Inspectors written by Transportation Dept., Federal Highway Administration and published by Government Printing Office. This book was released on with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: FHWA Publication No. FHWA-NHI-08-0106. February 2009. Explains the behavior of rivers in order to recognize changing conditions associated with unstable streams or scour at bridge foundations that may threaten the stability of the bridge. Provides tips and guidance on what to look for with regard to both stream instability, including lateral instability, degradation, and aggradation, and scour at bridges, including contraction scour, pier scour, and abutment scour. Also covered are plans of action and countermeasures, such as monitoring, flood watches, bridge closures, and river training countermeasures.
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 Monitoring Scour Critical Bridges written by Beatrice E. Hunt and published by Transportation Research Board. This book was released on 2009 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Knowledge Formalization for the Development of a Bridge Scour and Stream Stability Expert System written by Suzanne B. Pollon and published by . This book was released on 1994 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bridge Scour and Stream Instability Countermeasures written by U.s. Department of Transportation and published by CreateSpace. This book was released on 2015-03-10 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication identifies and provides design guidelines for bridge scour and stream instability countermeasures that have been implemented by various State departments of transportation (DOTs) in the United States. Countermeasure experience, selection, and design guidance are consolidated from other FHWA publications in this document to support a comprehensive analysis of scour and stream instability problems and provide a range of solutions to those problems. Selected innovative countermeasure concepts and guidance derived from practice outside the United States are introduced. Management strategies and guidance for developing a Plan of Action for scour critical bridges are outlined, and guidance is provided for scour monitoring using portable and fixed instrumentation. The results of recently completed National Cooperative Highway Research Program (NCHRP) projects are incorporated in the design guidance, including: countermeasures to protect bridge piers and abutments from scour; riprap design criteria, specifications, and quality control; and environmentally sensitive channel and bank protection measures. This additional material required expanding HEC-23 to two volumes. Volume 1 now contains a complete chapter on riprap design, specifications, and quality control as well as an expanded chapter on biotechnical countermeasures. The guidance on scour monitoring instrumentation has been updated and now includes additional installation case studies. Volume 2 contains 19 detailed design guidelines grouped into six categories, including countermeasures for: (1) stream instability (2) streambank and roadway embankment protection, (3) bridge pier protection, (4) abutment protection, (5) filter design, and (6) special applications.
Download or read book Report No FHWA RD written by United States. Federal Highway Administration. Offices of Research and Development and published by . This book was released on 1980 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scour and Erosion IX written by Yeh Keh-Chia and published by CRC Press. This book was released on 2018-10-16 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scour and Erosion IX contains the peer-reviewed scientific contributions presented at 9th International Conference on Scour and Erosion (ICSE 2018, Taipei, Taiwan, 5–8 November 2018), and includes recent accomplishments about scour and erosion in field observation, experimental laboratory work, theoretical development, numerical modeling and disaster management. The book covers fourteen topics: A. Internal erosion B. River, coastal, estuarine and marine scour and erosion C. Rock scour and erosion D. Sediment transport: grain scale and continuum scale E. Scour and erosion around structures F. Soil erosion, restoration mechanisms and conservation G. Hillslope conservation and debris flow H. Geotechnical issues related to scour and erosion I. Field observation and analyses J. Scour and erosion testing and experiment K. Remote sensing, instrumentation and monitoring L. Advanced numerical modelling of scour and erosion M. Natural hazards due to scour and erosion N. Management of scour/erosion and sediment.
Download or read book Bridge Scour and Stream Instability Countermeasures written by U.s. Department of Transportation and published by CreateSpace. This book was released on 2015-03-10 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication identifies and provides design guidelines for bridge scour and stream instability countermeasures that have been implemented by various State departments of transportation (DOTs) in the United States. Countermeasure experience, selection, and design guidance are consolidated from other FHWA publications in this document to support a comprehensive analysis of scour and stream instability problems and provide a range of solutions to those problems. Selected innovative countermeasure concepts and guidance derived from practice outside the United States are introduced. Management strategies and guidance for developing a Plan of Action for scour critical bridges are outlined, and guidance is provided for scour monitoring using portable and fixed instrumentation. The results of recently completed National Cooperative Highway Research Program (NCHRP) projects are incorporated in the design guidance, including: countermeasures to protect bridge piers and abutments from scour; riprap design criteria, specifications, and quality control; and environmentally sensitive channel and bank protection measures. This additional material required expanding HEC-23 to two volumes. Volume 1 now contains a complete chapter on riprap design, specifications, and quality control as well as an expanded chapter on biotechnical countermeasures. The guidance on scour monitoring instrumentation has been updated and now includes additional installation case studies. Volume 2 contains 19 detailed design guidelines grouped into six categories, including countermeasures for: (1) stream instability (2) streambank and roadway embankment protection, (3) bridge pier protection, (4) abutment protection, (5) filter design, and (6) special applications.
Download or read book Current Perspectives and New Directions in Mechanics Modelling and Design of Structural Systems written by Alphose Zingoni and published by CRC Press. This book was released on 2022-09-05 with total page 749 pages. Available in PDF, EPUB and Kindle. Book excerpt: Current Perspectives and New Directions in Mechanics, Modelling and Design of Structural Systems comprises 330 papers that were presented at the Eighth International Conference on Structural Engineering, Mechanics and Computation (SEMC 2022, Cape Town, South Africa, 5-7 September 2022). The topics featured may be clustered into six broad categories that span the themes of mechanics, modelling and engineering design: (i) mechanics of materials (elasticity, plasticity, porous media, fracture, fatigue, damage, delamination, viscosity, creep, shrinkage, etc); (ii) mechanics of structures (dynamics, vibration, seismic response, soil-structure interaction, fluid-structure interaction, response to blast and impact, response to fire, structural stability, buckling, collapse behaviour); (iii) numerical modelling and experimental testing (numerical methods, simulation techniques, multi-scale modelling, computational modelling, laboratory testing, field testing, experimental measurements); (iv) design in traditional engineering materials (steel, concrete, steel-concrete composite, aluminium, masonry, timber); (v) innovative concepts, sustainable engineering and special structures (nanostructures, adaptive structures, smart structures, composite structures, glass structures, bio-inspired structures, shells, membranes, space structures, lightweight structures, etc); (vi) the engineering process and life-cycle considerations (conceptualisation, planning, analysis, design, optimization, construction, assembly, manufacture, maintenance, monitoring, assessment, repair, strengthening, retrofitting, decommissioning). Two versions of the papers are available: full papers of length 6 pages are included in an e-book, while short papers of length 2 pages, intended to be concise but self-contained summaries of the full papers, are in this printed book. This work will be of interest to civil, structural, mechanical, marine and aerospace engineers, as well as planners and architects.
Download or read book Bridge Scour Monitoring Technologies written by Matthew Lueker and published by . This book was released on 2010 with total page 193 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bridge failure or loss of structural integrity can result from scour of riverbed sediment near bridge abutments or piers during high-flow events in rivers. In the past 20 years, several methods of monitoring bridge scour have been developed spanning a range of measurement approaches, complexities, costs, robustness, and measurement resolutions. This project brings together the expertise of Minnesota Department of Transportation (Mn/DOT) bridge engineers and researchers, university hydraulic and electrical engineers, field staff, and inspectors to take the first steps toward development of robust scour monitoring for Minnesota river bridges. The team worked with Mn/DOT engineers to identify variables of scour critical bridges that affect the application of scour monitoring technology. The research team will used this information to develop a Scour Monitoring Decision Framework (SMDF) that will aid Mn/DOT in selecting the best technologies for specific sites. The final component of the project will involve testing the SMDF on five bridges in a case-study type demonstration; work plans for two of the sites were developed for demonstration of deployed instrumentation.
Download or read book Flood Scour for Bridges and Highways written by Mohiuddin A. Khan and published by McGraw Hill Professional. This book was released on 2015-02-05 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt: Publisher's Note: Products purchased from Third Party sellers are not guaranteed by the publisher for quality, authenticity, or access to any online entitlements included with the product. Proven methods for preventing and mitigating bridge and highway flood scour Offering detailed guidelines on bridge scour countermeasures, this comprehensive resource provides a proactive strategy for the design and construction of bridges to prevent scour, as well as a reactive plan for post-flood disaster management. Topics discussed include erosion, causes of scour, AASHTO design codes, hydrology, hydraulics, scour analysis, inspection methods, and modern materials technology. Real-world case studies illustrate the concepts presented. The authoritative information in this practical guide will help you to develop more efficient and cost-effective design processes and bridge management systems for river bridges subjected to floods. Flood Scour for Bridges and Highways covers: Floods, scour problems, and mitigation River instability caused by flow obstructions Past failures and bridges vulnerable to failure Geotechnical and hydraulic issues at scour-critical rivers and bridges Hydrology, floods, and scour-critical bridges Estimating scour depths and selecting applicable countermeasures Inspections, ratings, and monitoring countermeasures FHWA, HEC-18, and HEC-23 scour countermeasures as remediation Innovative methods of flood control and disaster management
Download or read book Field Monitoring of Scour Critical Bridges written by Xiong Yu and published by . This book was released on 2010 with total page 197 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scour is a major threat to the safety of bridges. Instruments for the measurement and monitoring of bridge scour are necessary to study scour processes and to support bridge management. The lack of robust and economical scour monitoring devices prevents the implementation of a bridge scour monitoring program among bridge owners. This project explores the design and analyses of scour sensors using principles of Time Domain Reflectometry (TDR). The performance of a scour probe was first tested in laboratory simulated scour experiments. Three different signal analyses methods were developed to obtain the scour depth from TDR signals. Besides scour depth, additional information related to scour assessment, i.e. sediment density and electrical conductivity of water, were also determined from TDR signals. The sensing principles and analysis algorithms were validated from simulated scour tests under various conditions which are expected to be encountered in the field. The field conditions considered included: variation of sediment types, water conductivity, turbidity, air entrapment, and water elevation. These further validated the robustness of the scour sensing principles. Upon validation, a field worthy sensor was designed. The sampling area and effective measured dielectric constant were determined using a finite element analysis method. Evaluation of the sensor indicated that it was able to successfully monitor the scour processes (scour and refill) in real-time with high accuracy. Six TDR bridge scour sensors were installed at BUT-122-0606 bridge on SR 122 over the Great Miami River in Butler County, with assistance of project partners GRL Engineers Inc., and J&L Laboratories. Automatic monitoring units were installed to automatically take scour sensor signals and wirelessly transmit the sensor data. The sensors were installed using routine geotechnical site investigation tools and procedures. High quality signals were obtained, from which the development of scour adjacent to bridge piers was measured. The results are reasonable. The pilot study points to the promise of this new technology for long term bridge scour monitoring purposes. Continued evaluation and refinement of this new scour monitoring sensor system is highly recommended.
Download or read book Scour and Erosion written by John Harris and published by CRC Press. This book was released on 2016-10-14 with total page 1727 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scour and Erosion includes four keynote lectures from world leading researchers cutting across the themes of scour and erosion, together with 132 peer-reviewed papers from 34 countries, covering the principal themes of: - internal erosion - sediment transport - grain scale to continuum scale - advanced numerical modelling of scour and erosion - terrestrial scour and erosion- river and estuarine erosion including scour around structures, and - management of scour/erosion and sediment, including hazard management and sedimentation in dams and reservoirs. Scour and Erosion is ideal for researchers and industry working at the forefront of scour and erosion, and has applications in both the freshwater and marine environments.
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:
