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 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 Field Implementation and Evaluation of the Simple Cost effective Scour Sensor written by Farhad Ansari and published by . This book was released on 2011 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Study of an Innovative Bridge Scour Sensor written by Xinbao Yu and published by . This book was released on 2009 with total page 182 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 dissertation 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.

Download or read book Development of Passive and Active Piezoelectric Scour Depth Monitoring Sensors written by Morgan Leigh Funderburk and published by . This book was released on 2021 with total page 163 pages. Available in PDF, EPUB and Kindle. Book excerpt: Local scour is arguably the most pressing issue regarding the safety and longevity of overwater civil infrastructure. Scour is the leading cause of bridge collapse in the United States and therefore poses a great threat to public safety, disrupts local commerce, and costs millions of dollars in repairs. In the next century, the effects of climate changes will make more bridges susceptible to scour failure more than ever before. Many modern scour detection techniques do not provide continuous scour depth measurements, nor can they function under extreme flow conditions, which is when scour monitoring becomes most critical. This research aims to address the significant drawbacks of existing scour monitoring techniques by validating three piezoelectric driven-rod scour monitoring sensors developed using: hydrodynamic scour testing, localized velocity modeling, mathematical relationships and structural adaptations to mitigate environmental influences, as well as a novel, active soil interface sensing mechanism. The first proposed scour sensor, or piezo-rods, feature continuous piezoelectric polymer strips embedded within and along the length of slender cylindrical rods, which could then be driven into soil where scour is expected. When scour erodes away foundation material to reveal a portion of the piezo-rod, ambient fluid flow excitations would cause the piezoelectric element to output a voltage response corresponding to the dynamic bending strains of the sensor. The voltage response is dependent on both the structural dynamic properties of the sensor and the excitation fluid's velocity. By monitoring both shedding frequency and flow velocity, the exposed length of the piezo-rod (or scour depth) can be calculated. Hydrodynamic testing of the sensor system in a flume is discussed. Each rod was installed using a 3D-printed footing designed for ease of installation and stabilization during testing. Two series of experimental flume tests were conducted: (1) the piezo-rod was driven into sediment around a mock pier to collect scour data, and (2) the piezo-rod was used to monitor its own structural response by collecting vortex-shedding frequency data in response to varied flow velocities to establish a velocity-frequency (V-F) relationship. The sensors were installed in a layout designed to capture symmetric scour conditions around a scaled pier. In order to analyze the system out of steady-state conditions, water velocity was increased in stages during testing to induce different degrees of scour. As ambient water flow excited the portion of the exposed rods, the embedded piezoelectric element outputted a time-varying voltage signal. Different methods were then employed to extract the fundamental frequency of each rod, and the results were compared. Further testing was also performed to characterize the relationship between frequency outputs and flow velocity, which were previously thought to be independent. The results from soil-free velocity testing showed that the piezo-rod successfully captured structural vortex-shedding frequency comparable to state-of-the-art testing. A one-dimensional numerical model was developed using the V-F relationship to increase the accuracy of voltage-based length predictions of the piezo-rod. Two-dimensional flow modeling was also performed for predicting localized velocities within a complex flow-field. These velocities, in conjunction with the V-F relationship, were used to greatly improve length-predictive capabilities of the piezo rod. Higher mass ratio rods are known to be less susceptible to the influences of flowing-water excitations. Therefore, the second generation of the piezo-rod design aimed to increase the mass ratio of the scour sensor while also introducing more frequency features into the signal signature that can be used to determine length. Two variations of large-scale piezo-rods were developed and then optimized to have greater participation of high-order frequencies under free-vibration conditions using weights as localized masses. The results showed that a vibrational sensor could be made to output up to five modal frequencies, which are related to the number of additional participating weights. As a result of the velocity influence on the piezo-rod, and other passive sensors exited by flowing water, an active scour depth monitoring sensor using ultrasonic time domain reflectometry (UTDR) was developed. To make the third generation UTDR sensor, a long, slender plate is coupled with two flexible piezoelectric devices--macro-fiber composites--that propagate Lamb waves along the length of the plate to form the scour sensor. The hypothesis was that increasing scour depth would change the mechanical impedance of the system to cause measurable and unique signatures in the residual Lamb wave signals. The sensor was tested for sensitivity to external pressure using metal weights and was able to detect the position of the pressure up at a length of up to ~ 20 ft. The sensor was tested under simulated scour conditions, being buried in sand at various depths. The results showed that the Lamb wave scour sensor was capable of reliably detecting a soil interface at 1 ft intervals. The scour sensor was also able to detect uncompacted soil interfaces, which is important considering the issue of scour hole refill following an extreme event. Overall, the Lamb wave UTDR sensor was demonstrated to be a feasible sensing mechanism for scour depth monitoring.

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 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 Monitoring of Bridge Stability Due to Scour Using Remote and Low cost Optical Sensors written by Mohamed Saafi and published by . This book was released on 2008 with total page 51 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scour is the erosion of the stream and banks near foundations, piers and abutments of a bridge which is also referred to as bridge scour. Scour of the bed near bridge piers and abutments has resulted in more bridge failures than all other causes in recent years. Highway bridge failures cost millions of dollars each year as a result of both direct costs necessary to replace and restore bridges, and indirect costs related to disruption of transportation facilities. There are two issues associated with such scour induced damage to bridge pier footings. The first effect is the loss of foundation material which exposes the footing and lowers its factor of safety with regard to sliding or lateral deformation. The greatest loss of sediment to scour occurs at high water velocities, such as during floods. Secondly, pier movement may occur as a result of material loss beside and beneath the base of the footing which produces undesired stresses in the bridge structure and ultimately results in structural collapse. Scour can go undetected for many years until a catastrophic disaster occurs. This problem cannot be entirely eliminated, but can be corrected when scour does occur. A major obstacle in correcting this dilemma is determining when and where the crisis is occurring. Many methods have been used in determining whether or not scour is present. Some of these techniques are permanently attached to the structures and others can be transported from bridge to bridge to measure the scour. Also, some of the current procedures cannot work in some conditions and places. Recently, the National Cooperative Highway Research Program (NCHRP) recognized the need of more research activities to develop, test and evaluate instrumentations that would be both technically and economically feasible for use in monitoring maximum scour depth at bridge piers and abutments. The scour monitoring devices should be low cost, reliable, and capable of installation on or near a bridge pier. Therefore, the objective of this project is to develop a low-cost optical system to detect scour. The proposed optical system was developed and evaluated through large scale scour tests. Results indicated that the proposed sensor is capable of detecting scour depth under flood conditions.

Download or read book Structural Health Monitoring for Suspension Bridges written by Yang Deng and published by Springer. This book was released on 2018-12-19 with total page 243 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents extensive information on structural health monitoring for suspension bridges. During the past two decades, there have been significant advances in the sensing technologies employed in long-span bridge health monitoring. However, interpretation of the massive monitoring data is still lagging behind. This book establishes a series of measurement interpretation frameworks that focus on bridge site environmental conditions, and global and local responses of suspension bridges. Using the proposed frameworks, it subsequently offers new insights into the structural behaviors of long-span suspension bridges. As a valuable resource for researchers, scientists and engineers in the field of bridge structural health monitoring, it provides essential information, methods, and practical algorithms that can facilitate in-service bridge performance assessments.

Download or read book Accurate and Scalable Bridge Health Monitoring Using Drive by Vehicle Vibrations written by Jingxiao Liu and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this research is to achieve accurate and scalable bridge health monitoring (BHM) by learning, integrating, and generalizing the monitoring models derived from drive-by vehicle vibrations. Early diagnosis of bridge damage through BHM is crucial for preventing more severe damage and collapses that could lead to significant economic and human losses. Conventional BHM approaches require installing sensors directly on bridges, which are expensive, inefficient, and difficult to scale up. To address these limitations, this research uses vehicle vibration data when the vehicle passes over the bridge to infer bridge conditions. This drive-by BHM approach builds on the intuition that the recorded vehicle vibrations carry information about the vehicle-bridge interaction (VBI) and thus can indirectly inform us of the dynamic characteristics of the bridge. Advantages of this approach include the ability for each vehicle to monitor multiple bridges economically and eliminating the need for on-site maintenance of sensors and equipment on bridges. Though the drive-by BHM approach has the above benefits, implementing it in practice presents challenges due to its indirect measurement nature. In particular, this research tackles three key challenges: 1) Complex vehicle-bridge interaction. The VBI system is a complex interaction system, making mathematical modeling difficult. The analysis of vehicle vibration data to extract the desired bridge information is challenging because the data have complex noise conditions as well as many uncertainties involved. 2) Limited temporal information. The drive-by vehicle vibration data contains limited temporal information at each coordinate on the bridge, which consequently restricts the drive-by BHM's capacity to deliver fine-grained spatiotemporal assessments of the bridge's condition. 3) Heterogeneous bridge properties. The damage diagnostic model learned from vehicle vibration data collected from one bridge is hard to generalize to other bridges because bridge properties are heterogeneous. Moreover, the multi-task nature of damage diagnosis, such as detection, localization, and quantification, exacerbates the system heterogeneity issue. To address the complex vehicle-bridge interaction challenge, this research learns the BHM model through non-linear dimensionality reduction based on the insights we gained by formulating the VBI system. Many existing physics-based formulations make assumptions (e.g., ignoring non-linear dynamic terms) to simplify the drive-by BHM problem, which is inaccurate for damage diagnosis in practice. Data-driven approaches are recently introduced, but they use black-box models, which lack physical interpretation and require lots of labeled data for model training. To this end, I first characterize the non-linear relationship between bridge damage and vehicle vibrations through a new VBI formulation. This new formulation provides us with key insights to model the vehicle vibration features in a non-linear way and consider the high-frequency interactions between the bridge and vehicle dynamics. Moreover, analyzing the high-dimensional vehicle vibration response is difficult and computationally expensive because of the curse of dimensionality. Hence, I develop an algorithm to learn the low-dimensional feature embedding, also referred to as manifold, of vehicle vibration data through a non-linear and non-convex dimensionality reduction technique called stacked autoencoders. This approach provides informative features for achieving damage estimation with limited labeled data. To address the limited temporal information challenge, this research integrates multiple sensing modalities to provide complementary information about bridge health. The approach utilizes vibrations collected from both drive-by vehicles and pre-existing telecommunication (telecom) fiber-optic cables running through the bridge. In particular, my approach uses telecom fiber-optic cables as distributed acoustic sensors to continuously collect bridge dynamic strain responses at fixed locations. In addition, drive-by vehicle vibrations capture the input loading information to the bridge with a high spatial resolution. Due to extensively installed telecom fiber cables on bridges, the telecom cable-based approach also does not require on-site sensor installation and maintenance. A physics-informed system identification method is developed to estimate the bridge's natural frequencies, strain and displacement mode shapes using telecom cable responses. This method models strain mode shapes based on parametric mode shape functions derived from theoretical bridge dynamics. Moreover, I am developing a sensor fusion approach that reconstructs the dynamic responses of the bridge by modeling the vehicle-bridge-fiber interaction system that considers the drive-by vehicle and telecommunication fiber vibrations as the system input and output, respectively. To address the heterogeneous bridge properties challenge, this research generalizes the monitoring model for one bridge to monitor other bridges through a hierarchical model transfer approach. This approach learns a new manifold (or feature space) of vehicle vibration data collected from multiple bridges so that the features transferred to such manifold are sensitive to damage and invariant across multiple bridges. Specifically, the feature is modeled through domain adversarial learning that simultaneously maximizes the damage diagnosis performance for the bridge with available labeled data while minimizing the performance of classifying which bridge (including those with and without labeled data) the data came from. Moreover, to learn multiple diagnostic tasks (including damage detection, localization, and quantification) that have distinct learning difficulties, the framework formulates a feature hierarchy that allocates more learning resources to learn tasks that are hard to learn, in order to improve learning performance with limited data. A new generalization risk bound is derived to provide the theoretical foundation and insights for developing the learning algorithm and efficient optimization strategy. This approach allows a multi-task damage diagnosis model developed using labeled data from one bridge to be used for other bridges without requiring training data labels from those bridges. Overall, this research offers a new approach that can achieve accurate and scalable BHM by learning, integrating, and generalizing monitoring models learned from drive-by vehicle vibrations. The approach enables low-cost and efficient diagnosis of bridge damage before it poses a threat to the public, which could avoid the enormous loss of human lives and property.

Download or read book Bridge Optimization written by Yun Lai Zhou and published by BoD – Books on Demand. This book was released on 2020-02-05 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a collection of several applications for condition monitoring and damage identification in bridge structures. Bridge structural condition monitoring is essential since it can provide early warning of potential defects in bridges, which may induce catastrophic accidents and result in huge economic loss. Such bridge condition monitoring relies on sensing techniques, especially advanced sensing techniques that can provide detailed information on bridge structures. Additionally, postprocessing systems can interpret the captured data and warn of any potential faults. This book will give students a thorough understanding of bridge condition monitoring.

Download or read book Framework of Damage Detection in Vehicle Bridge Coupled System written by Xuan Kong and published by LAP Lambert Academic Publishing. This book was released on 2013 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: Most vibration-based damage identification methods make use of measurements directly from bridge structures with attached sensors. The present study aimed to develop new methodologies to eventually detect bridge damages such as scour using the dynamic response of the vehicle. A framework of damage identification and an optimization method was developed first. Secondly, a new methodology using the transmissibility of vehicle and bridge responses was developed to detect bridge damages. Then, a tractor-trailer test system was designed to obtain reliable response and extract bridge modal properties from the dynamic response of moving vehicles. These developed methodologies were applied to detect scour damage from the response of bridge and/or vehicles. The scour effect on a single pile was studied and methods of scour damage detections were proposed. A monitoring system using fiber optic sensors was designed and tested in the laboratory and is being applied to a field bridge. Finally, the scour effect on the response of the entire bridge and the traveling vehicle was also investigated under the bridge-vehicle-wave interaction, which in turn was used to detect the bridge scour.

Download or read book Fusion of Numerical Modeling and Innovative Sensing to Advance Bridge Scour Research and Practice written by Junliang Tao and published by . This book was released on 2013 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bridge scour is the erosion of sediments around bridge piers or abutments due to flowing water. It is the number one cause of bridge failures in the United States. However, the mechanism of bridge scour remains a mystery due to the complex interaction between structures, flow, and sediments; there is also an urgent demand to develop countermeasures reducing the risk caused by bridge scour. This dissertation work aims to provide innovative solutions to address such challenges through highly interdisciplinary efforts. A tremendous effort has also been placed to review and synthesize the existing literature. Computational Fluid Dynamics (CFD) technique is employed to simulate the flow and scour patterns around bridge piers with different geometries. The effects of pier shape, aspect ratio and attack angle on the flow and scour patterns are evaluated. The findings of this work not only further advance the understanding of scour, but also provide insightful practical implications. A numerical simulation framework integrating advanced CFD techniques and a novel sediment transport model is also developed, aiming to model the scour process. The uniqueness of this advanced model is that it incorporates the influence of turbulence, which plays a crucial role in the process of scouring but has been overlooked for decades. To facilitate the characterization of the turbulence at the interface of sediment and river flow, bio-inspired flow sensors are developed. The innovative sensors mimic the function and structure of the hair cells in fish, which is sensitive to turbulence in flow. Smart material (piezoelectric microfiber) is employed to construct the artificial hair cell and the unique patterning of electrodes enables the linear sensitivity as well as the directional sensitivity of the sensor. Three designs are proposed, modeled and optimized. The performance of the prototype sensors is evaluated through laboratory experiments. A field monitoring system is designed and deployed in the field to remotely monitor the evolution of the scour depth around real bridge piers. This system includes an innovative sensor based on Time Domain Reflectometry (TDR) technique and the sensor is proved to be sensitive, durable and cost effective. It also includes a field data acquisition system, which automatically collects the TDR data and transmits the data wirelessly. The scour depth data can be utilized to calibrate the various scour depth prediction equations. It can also be integrated into the bridge risk management system to assist in decision making.

Download or read book Monitoring Bridge Scour Using Fiber Optic Sensors written by Chunsheng Cai and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Sensor Characterization for Long term Remote Monitoring of Bridge Piers written by Joseph Caleb Philipps and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Structural instability of bridge piers resulting from scour or other natural hazards can lead to bridge collapse. A monitoring system that analyzes bridge pier behavior could prevent this type of failure by detecting conditions, such as pier tilt, that may lead to instability. The sensor system developed during this project consists of an array of low cost tilt sensors, deployed on both the pier and superstructure of a bridge, to monitor structural behavior of a bridge pier. The goal of the research presented in this thesis is to characterize the behavior of the sensors that are to be used in this system. Characterization of the sensors required analysis of several distinct sensor attributes that can often be specific to individual sensors. For example, this analysis included sensor calibration, drift analysis, characterization of temperature effects, in-situ sensor behavior, and characterization of the sensor system's resolution. This thesis will describe the process of designing test systems required to complete the sensor characterization. The experiments performed to characterize the sensors using these test systems will be defined. Finally, the results of the testing conducted to characterize sensor behavior, and the implications of sensor characteristics on the final system's operational capability will be discussed.

Download or read book Manual on Scour at Bridges and Other Hydraulic Structures written by Amanda Kitchen and published by . This book was released on 2021 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Monitoring Bridge Scour with Buried Transmitters written by Walter A. Winter and published by . This book was released on 1995 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bridge scour is the major cause of bridge failure. Scour occurs when waterways are at high stage and the rock and sediments that support bridge piers are removed by water action. Monitoring and quantifying scour is considered a high priority problem by the Caltrans Division of Structures. A conceptual design was developed which would use buried scour sensors placed at known depths in drilled holes. They would sense by tilting when scour reached their depth and would transmit that information to the surface with low frequency radio. A design was conceptualized, and Stolar Research Group of Raton, New Mexico, submitted a proposal to build the concept system. Stolar Research's technical discussion and proposal constitute the technical content of this report and appear as an appendix.