Bridges Structural Health Monitoring and Deterioration Detection Synthesis of Knowledge and Technology

INE/AUTC 10.0

Damage identification in structural health monitoring: a brief review from its implementation to the Use of data-driven applications

The damage identification process provides relevant information about the current state of a structure under inspection, and it can be approached from two different points of view. The first approach uses data-driven algorithms, which are usually associated with the collection of data using sensors. Data are subsequently processed and analyzed. The second approach uses models to analyze information about the structure. In the latter case, the overall performance of the approach is associated with the accuracy of the model and the information that is used to define it. Although both approaches are widely used, data-driven algorithms are preferred in most cases because they afford the ability to analyze data acquired from sensors and to provide a real-time solution for decision making; however, these approaches involve high-performance processors due to the high computational cost. As a contribution to the researchers working with data-driven algorithms and applications, this work presents a brief review of data-driven algorithms for damage identification in structural health-monitoring applications. This review covers damage detection, localization, classification, extension, and prognosis, as well as the development of smart structures. The literature is systematically reviewed according to the natural steps of a structural health-monitoring system. This review also includes information on the types of sensors used as well as on the development of data-driven algorithms for damage identification.Peer ReviewedPostprint (published version

Truck-based mobile wireless sensor networks for the experimental observation of vehicle–bridge interaction

Heavy vehicles driving over a bridge create a complex dynamic phenomenon known as vehicle–bridge interaction. In recent years, interest in vehicle–bridge interaction has grown because a deeper understanding of the phenomena can lead to improvements in bridge design methods while enhancing the accuracy of structural health monitoring techniques. The mobility of wireless sensors can be leveraged to directly monitor the dynamic coupling between the moving vehicle and the bridge. In this study, a mobile wireless sensor network is proposed for installation on a heavy truck to capture the vertical acceleration, horizontal acceleration and gyroscopic pitching of the truck as it crosses a bridge. The vehicle-based wireless monitoring system is designed to interact with a static, permanent wireless monitoring system installed on the bridge. Specifically, the mobile wireless sensors time-synchronize with the bridge's wireless sensors before transferring the vehicle response data. Vertical acceleration and gyroscopic pitching measurements of the vehicle are combined with bridge accelerations to create a time-synchronized vehicle–bridge response dataset. In addition to observing the vehicle vibrations, Kalman filtering is adopted to accurately track the vehicle position using the measured horizontal acceleration of the vehicle and positioning information derived from piezoelectric strip sensors installed on the bridge deck as part of the bridge monitoring system. Using the Geumdang Bridge (Korea), extensive field testing of the proposed vehicle–bridge wireless monitoring system is conducted. Experimental results verify the reliability of the wireless system and the accuracy of the vehicle positioning algorithm.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90810/1/0964-1726_20_6_065009.pd

Development of low-cost sensors for structural health monitoring applications

(English) There is increasing interest in developing low-cost sensors for economical structural health monitoring of civil engineering infrastructures. In addition to their price, they have the additional benefit of being easily connected to low-cost microcontrollers such as Arduino. A reliable data acquisition system based on Arduino technology can further lower the cost of data collection and monitoring, enabling long-term monitoring at an affordable cost. This thesis proposes the following four high-precision low-cost monitoring systems.Firstly, to correctly measure structural responses, a Cost Hyper-Efficient Arduino Product (CHEAP) has been developed. CHEAP is a system made up of five synchronized accelerometers connected to an Arduino microcontroller that works as a data collecting device. CHEAP is a uniaxial MEMS accelerometer with a sampling frequency of 85 Hz. To validate its performance, laboratory experiments were carried out and the results were compared with those of two high-precision accelerometers (PCB393A03 and PCB 356B18).Secondly, a unique low-cost inclinometer is presented, the Low-cost Adaptable Reliable Angle-meter (LARA), which measures inclination through the fusion of different sensors: five gyroscopes and five accelerometers. LARA combines a microcontroller based on Internet of Things technology (NODEMCU), allows wireless data transmission, and free commercial software for data collection (SerialPlot). To confirm the precision and resolution of this device, its measurements under laboratory conditions were compared with the theoretical ones and with those of a commercial inclinometer (HI-INC). Laboratory results of a load test on a beam demonstrate LARA's remarkable accuracy. It is concluded that the accuracy of LARA is sufficient for its application in detecting bridge damage.Thirdly, the effect of combining similar range sensors to investigate the increase of the accuracy and mitigation of the ambiental noises, is also elucidated. To investigate the sensor combination theory, a measuring equipment composed of 75 contactless ranging sensors controlled by only two microcontrollers (Arduinos), was built. The 75 sensors are 25 HC-SR04 (analog), 25 VL53L0X (digital), and 25 VL53L1X. (digital). In addition, the impact of various environmental conditions on the standard deviation, distribution functions, and error level of these sensors (HC-SR04, VL53L0X, and VL53L1X) is determined.Finally, a novel remote versatile data acquisition system is presented that allows the recording of time with microsecond resolution for the subsequent synchronization of the acquired data of the wireless sensors located at various points of a structure. This functionality is what would allow its application to static or quasi-static load tests or to the modal analysis of structures. The system developed has a noise density of 51 g/Hz and a sampling frequency of 333 Hz. This device was used to identify the eigenfrequencies and modal analysis of several structures (polvorín footbridges in Barcelona and Andoain Bridge, Donostia-San Sebastian). The comparison of the modal analysis of the Andoain Bridge using the acquired data of the developed accelerometer and data acquisition equipment with those of commercial accelerometers (PCB 607A61) were satisfactory.The low-cost accelerometer, inclinometer and data acquisition system developed and validated in this thesis can make SHM and infrastructure damage detection a reality at low cost, long term and remotely.(Español) Cada vez hay más interés en desarrollar sensores baratos para conocer de manera económica el estado de las infraestructuras civiles. Además de su precio, estos sensores tienen la ventaja añadida de poder conectarse fácilmente a microcontroladores de bajo coste como Arduino. Un sistema fiable de adquisición de datos basado en la tecnología Arduino puede disminuir aún más el coste de la recogida de datos y la monitorización, lo que permitiría una monitorización a largo plazo a un coste asequible. Esta tesis propone los cuatro siguientes sistemas de monitorización de alta precisión y bajo coste.En primer lugar, para medir correctamente las respuestas estructurales, se ha desarrollado el Cost Hyper-Efficient Arduino Product (CHEAP). CHEAP es un sistema compuesto por cinco acelerómetros sincronizados de bajo coste conectados a un microcontrolador Arduino que hace el papel de dispositivo de recogida de datos. CHEAP es un acelerómetro MEMS uniaxial con una frecuencia de muestreo de 85 Hz. Para validar su rendimiento, se efectuaron unos experimentos de laboratorio y sus resultados se compararon con los de dos acelerómetros de alta precisión (PCB393A03 y PCB 356B18). En segundo lugar, se presenta un inclinómetro de bajo coste, un Low-cost Adaptable Reliable Angle-meter (LARA), que mide la inclinación mediante la fusión de distintos sensores: cinco giroscopios y cinco acelerómetros. LARA combina un microcontrolador basado en la tecnología del Internet de las Cosas (NODEMCU), que permite la transmisión inalámbrica de datos, y un software comercial gratuito para la recogida de datos (SerialPlot). Para confirmar la precisión y resolución de este dispositivo, se compararon sus mediciones en condiciones de laboratorio con las teóricas y con las de un inclinómetro comercial (HI-INC). Los resultados de laboratorio de una prueba de carga en una viga demuestran la notable precisión de LARA. Se concluye que la precisión de LARA es suficiente para su aplicación en la detección de daños en puentes.En tercer lugar, también se dilucida el efecto de la combinación de sensores de rango similar para investigar el aumento de la precisión y la mitigación de los ruidos ambientales. Para investigar la teoría de la combinación de sensores, se construyó un equipo de medición compuesto por 75 sensores para la medición de distancias acoplados a dos microcontroladores de Arduino. Los 75 sensores son 25 HC-SR04 (analógicos), 25 VL53L0X (digitales) y 25 VL53L1X (digitales). Además, se determina el impacto de diversas condiciones ambientales en la desviación estándar, las funciones de distribución y el nivel de error de estos sensores.Por último, se presenta un novedoso y versátil sistema de adquisición de datos a distancia que permite el registro del tiempo con una resolución de microsegundos para la sincronización posterior de las lecturas de los sensores inalámbricos situados en diversos puntos de una estructura. Esta funcionalidad es lo que permitiría su aplicación a pruebas de carga estáticas o quasi-estaticas o al análisis modal de las estructuras. El sistema desarrollado tiene una densidad de ruido de 51 g/Hz y una frecuencia de muestreo de 333 Hz. Este dispositivo se utilizó para identificar las frecuencias propias y los modos de vibración de varias estructuras (pasarelas polvorín en Barcelona y Puente de Andoain, Donostia-San Sebastian). Los modos calculados en una de ellas, el Puente de Andoain, a partir de los datos obtenidos con el acelerómetro y sistema de adquisición de datos desarrollado se comparan satisfactoriamente con los de sensores comerciales (PCB 607A61). El acelerómetro, el inclinómetro y el sistema de adquisición de datos de bajo coste desarrollados y validados en esta tesis pueden hacer realidad la SHM y la detección de daños en infraestructuras a bajo coste, a largo plazo y de forma remota.Postprint (published version

Wireless sensor system for infrastructure health monitoring

In this thesis, radio frequency identification (RFID)-based wireless sensor system for infrastructure health monitoring (IHM) is designed and developed. It includes mountable semi-passive tag antenna integrated sensors capable of measuring critical responses of infrastructure such as dynamic acceleration and strain. Furthermore, the system is capable of measuring structural displacement. One of the most important parts of this system is the relatively small, tunable, construction material mountable RFID tag antenna. The tag antenna is electronically integrated with the sensors. Leading to the process of developing tag antenna integrated sensors having satisfactory wireless performance (sensitivity and read range) when mounted on concrete and metal structural members, the electromagnetic performance of the tag antenna is analyzed and optimized using both numerical and experimental procedures. Subsequently, it is shown that both the simulation and the experimental measurement results are in good agreement. The semi-passive RFID-based system is implemented in a wireless IHM system with multiple sensor points to measure dynamic acceleration and strain. The developed system can determine the natural frequencies of infrastructure and identify any state changes of infrastructure by measuring natural frequency shifts. Enhancement of the spectral bandwidth of the system has been performed under the constraints of the RFID hardware. The influence of the orientation and shape of the structural members on wireless power flow in the vicinity of those members is also investigated with the RFID reader-tag antenna system in both simulation and experiments. The antenna system simulations with a full-scale structural member have shown that both the orientation and the shape of the structural member influence the wireless power flow towards and in the vicinity of the member, respectively. The measurement results of the conducted laboratory experiments using the RFID antenna system in passive mode have shown good agreement with simulation results. Furthermore, the system’s ability to measure structural displacement is also investigated by conducting phase angle of arrival measurements. It is shown that the system in its passive mode is capable of measuring small structural displacements within a short wireless distance. The benchmarking of the developed system with independent, commercial, wired and wireless measurement systems has confirmed the ability of the RFID-based system to measure dynamic acceleration and strain. Furthermore, it has confirmed the system’s ability to determine the natural frequency of an infrastructure accurately. Therefore, the developed system with wireless sensors that do not consume battery power in data transmission and with the capability of dynamic response measurement is highly applicable in IHM

COMPARISON OF FEASIBILITY OF RISK MONITORING IN BUILDINGS IN TWO WIRELESS SENSOR NETWORK: MICA MOTE AND MEMS

In this paper feasibility of risk monitoring of buildings in two wireless sensor network is presented,firstly by using MICA Mote and then by MEMS.Also,it will be verified that the MEMS sensors are superior as it provides high quality sensor data and no data loss as compared to MICA Mote.In order to assess earthquakes the structures is monitored firstly by using a smart sensor based on the Berkeley Moteplatform.The Mote has on-board microprocessor and ready-made wireless communication capabilities. In this paper, the performance of the Mote is investigated through shakingtable tests employing a two-story steel structur. The feasibility of risk monitoring for buildings is also discussed.In building monitoring using MEMS,a low power wireless network employing capacitive MEMS which is custom-developed,3D accelerated sensor and a low power readout ASIC is used at the sensor nodes.After the the earthquake, the plastic hinge activation of structure is being measured using MEM sensor either periodically or on demand by the base station.During an earthquake the accelerometers are used to measure the seismic response of the structure. The seismic response is recorded by the accelerometer based on the local acceleration data and remote triggering from the base station.The base station is based on acceleration data from multiple sensors across the structure.In a 800 MHZ band,a low power architecture had been implemented over an 802.15.4 MAC

Laboratory validation of an Arduino based accelerometer designed for SHM applications

Nowadays, low-cost sensors based on low-cost microcontrollers and microprocessors are gaining a lot of attention from researchers. This increasing interest is due to the fact that the implementation of low-cost solutions may make Structural Health Monitoring (SHM) applicable and affordable to structures with a low budget for their SHM. However, many of the present solutions do not have comparable accuracy and resolution with those of the traditional commercial accelerometers. Also, the noise density of these newly developed prototypes has not been checked through laboratory experiments. In fact, the characteristics of the designed and created accelerometer are simply copied from the datasheet of the chipset used to develop the solution. Moreover, the sampling frequency of the majority of the available low-cost solutions usually is lower than 100 Hz. This paper presents a consistent work with the development of a low-cost wireless accelerometer with a sampling frequency of 333 Hz and noise density of 51µg/vHz. This accelerometer's accuracy, noise density, and reliability are evaluated through a series of laboratory experiments. It is essential to mention that this accelerometer does not need any additional data acquisition equipment and is self-sufficient.Postprint (published version

A multisensing setup for the intelligent tire monitoring

The present paper offers the chance to experimentally measure, for the first time, the internal tire strain by optical fiber sensors during the tire rolling in real operating conditions. The phenomena that take place during the tire rolling are in fact far from being completely understood. Despite several models available in the technical literature, there is not a correspondently large set of experimental observations. The paper includes the detailed description of the new multi-sensing technology for an ongoing vehicle measurement, which the research group has developed in the context of the project OPTYRE. The experimental apparatus is mainly based on the use of optical fibers with embedded Fiber Bragg Gratings sensors for the acquisition of the circumferential tire strain. Other sensors are also installed on the tire, such as a phonic wheel, a uniaxial accelerometer, and a dynamic temperature sensor. The acquired information is used as input variables in dedicated algorithms that allow the identification of key parameters, such as the dynamic contact patch, instantaneous dissipation and instantaneous grip. The OPTYRE project brings a contribution into the field of experimental grip monitoring of wheeled vehicles, with implications both on passive and active safety characteristics of cars and motorbikes

RFID-Based Wireless Multi-Sensory System for Simultaneous Dynamic Acceleration and Strain Measurements of Civil Infrastructure

© 2001-2012 IEEE. In this paper, we develop a radio frequency identification (RFID)-based wireless multi-sensory infrastructure health monitoring (IHM) system that can simultaneously measure dynamic acceleration and strain. The system consists of a novel multi-sensor integrated semi-passive ultra-high frequency (UHF) tag antenna that can be mounted on civil infrastructure elements; even made out of metal. The system is capable of measuring 3-axis dynamic acceleration and strain with spectral bandwidths of 40 Hz and 26.5 Hz, respectively. The natural frequency determination of infrastructure by the dynamic acceleration and strain measurements of the proposed system is accurate to 60 mHz. Benchmarking of the RFID-based wireless multi-sensory system is provided by comprehensive comparison of the results with measurements from a commercial wireless strain measurement system. The proposed system has 30 mHz natural frequency determination error when compared with dynamic strain measurement from the commercial system

Prototype Development of a Deployable Measurement System for Civil Infrastructures

학위논문(석사)--서울대학교 대학원 :공과대학 건설환경공학부,2019. 8. 김호경.Although the science of theoretical fluid mechanics has been well developed and the computational methods are rapidly advancing, the measurement of the wind-induced pressure and vibration of civil infrastructures, such as long-span bridges, high-rise buildings, wind barriers, etc., is essential to understand the structural performance of the infrastructure. The conventional measurement system requires many devices such as a power source, a data acquisition device, sensors, cables, etc., which pose difficulty in installation and measurement on bridges or buildings that are in use. Therefore, it is necessary to develop a miniaturized device so that researchers and engineers can easily obtain wind-induced pressure and vibration data at any desired locations without interrupting the use of the infrastructure. This paper proposes a prototype development which can measure wind pressure acting on a structure and acceleration of the structure. In this study, micro-electronic-mechanical-system (MEMS) sensors are used in the prototype device such as acceleration and pressure sensors. It is expected that the successful development of the sensor module will help engineers and researchers measure wind pressure acting on a structure and associated structural vibration.본 연구에서는 토목 인프라 구조물의 동적 특성을 계측하기 위한 설치 편의형 계측 시스템 개발에 대한 연구를 수행하였다. 이론적 유체역학이 지속적으로 발전되었고 유체의 흐름을 해석하는 방법들이 빠르게 개발되었지만, 장대교량과 고층빌딩, 방풍벽 등과 같이 바람의 영향으로 진동이 크게 발생하는 인프라 구조물들은 실제 움직임을 계측하여 동적 특성을 분석하는 것이 필수적이다. 현재 계측 시스템은 발전기와 데이터 저장장치, 센서, 케이블 등 많은 장비가 필요하기 때문에 이를 운영 중인 교량과 고층빌딩에 설치하여 계측하는 과정에 많은 어려움이 있다. 이와 같은 문제를 해결하기 위해 전원과 데이터 저장장치, 센서가 일체화된 무선 계측 장치를 개발할 필요가 있으며, 이는 연구자와 공학자들이 인프라 구조물 운영에 영향을 주지 않으면서 원하는 지점에서 구조물의 진동을 계측하는 것에 도움을 줄 것이다. 이 연구에서는 GPS를 이용하여 기기간 시간 동기화를 유지하고, MEMS 가속도 센서 및 MEMS 압력 센서를 활용하여 구조물의 진동과 구조물에 작용하는 압력을 계측하는 설치 편의형 계측 장치를 제안한다.TABLE OF CONTENTS CHAPTER 1 1 INTRODUCTION 1 1.1 RESEARCH BACKGROUND 1 1.2 PREVIOUS WORK AND PROBLEM DEFINITION 3 1.3 ISSUES OF COMMERCIAL WIRELESS SENSOR 3 1.4 ISSUES OF DESIGNED WIRELESS SENSOR 4 1.5 PROTOTYPE OF DEPLOYABLE MEASUREMENT DEVICE 5 CHAPTER 2 7 TIME SYNCHRONIZATION 7 2.1 MICRO CONTROL UNIT (MCU) CLOCK 7 2.2 REAL TIME CLOCK (RTC) 8 2.3 GLOBAL POSITIONING SYSTEM (GPS) 10 CHAPTER 3 13 ACCELEROMETER 13 3.1 TYPE OF ACCELEROMETER 13 3.1.1 Piezo electric type accelerometer 13 3.1.2 Capacitive type accelerometer 14 3.2 ACCELEROMETER VALIDATION TEST 15 3.2.1 Sinusoidal motion 16 3.2.2 Seismic motion 19 3.3 APPLICATION OF PROPOSED DEVICE 20 3.3.1 Suspended footbridge 21 CHAPTER 4 34 PRESSURE SENSOR 34 4.1 TYPE OF PRESSURE SENSOR 34 4.1.1 Piezo-resistive type pressure sensor 34 4.2 PRESSURE SENSOR VALIDATION TEST 35 4.2.1 Pressure change test according to volume change in closed cylinder 35 4.2.2 Pressure change test according to wind speed in wind tunnel test 37 CHAPTER 5 42 SUMMARY AND CONCLUSIONS 42 REFERENCES 44Maste