Structural Engineering Commons^™

Mobile-Manipulating Uavs For Sensor Installation, Bridge Inspection And Maintenance, Paul Oh

INSPIRE-UTC Annual Meetings

Mobile manipulating UAVs have great potential for bridge inspection and maintenance. Since 2002, the PI has developed UAVs that could fly through in-and-around buildings and tunnels. Collision avoidance in such cluttered near-Earth environments has been a key challenge. The advent of light-weight, computationally powerful cameras led to breakthroughs in SLAM even though SLAM-based autonomous aerial navigation around bridges remains an unsolved problem.

In 2007, the PI integrated a mobile manipulation function into UAVs, greatly extending the capabilities of UAVs from passive survey of environments with cameras to active interaction with environments using limbs. Mobile-manipulating UAVs have since been demonstrated to …

Quantitative Bridge Inspection Ratings Using Autonomous Robotic Systems, Anil Agrawal

INSPIRE-UTC Annual Meetings

The 2001 study sponsored by FHWA raised serious concern on the consistency and reliability of visual inspection. Although consistent ratings can be obtained with a good QA/QC program, based on a recent study by the PI, the concern for reliability of defect detection remains. With the adoption of the recent AASHTO Manuel for Bridge Element Inspection, the new inspection approach not only requires rating for bridge elements, but also the location and extent of deterioration. Since autonomous robotic systems generate an enormous amount of inspection data, deducing from the data to a simple rating along with the location and extent …

Hyperspectral Image Analysis For Mechanical And Chemical Properties Of Concrete And Steel Surfaces, Genda Chen

INSPIRE-UTC Annual Meetings

A typical human eye will respond to wavelengths from approximately 400 to 700 nm. A hyperspectral camera can extend the wavelength to as high as 2500 nm. This extension will allow engineers to find objects, identify materials, and detect processes on structural surface, which cannot be done with visual inspection.

This project aims to develop an open-source catalogue of concrete and steel surfaces and their spectral/spatial features (discoloration, characteristic wavelength, roughness, texture, shape, etc.), extract spatial/spectral features of hyperspectral images, and develop/train a multi-class classification or regression classifier through machine learnings (supervised and/or semi-supervised), and validate the classifier as a …

3d Microwave Camera For Concrete Delamination And Steel Corrosion Detection, R. Zoughi

INSPIRE-UTC Annual Meetings

Corrosion of embedded steel reinforcement in concrete leads to concrete cracking and delamination, followed by increased salt and moisture permeation and further damage. Invisibility of the embedded rebar in combination with physical inaccessibility in elevated bridges presents a challenge in the assessment of RC bridge elements. Wideband (3D) microwave synthetic aperture radar (SAR) imaging techniques that can be integrated into a UAV offer a practical solution to overcome this challenge.

This project aims to develop and optimize a 3D microwave camera for bridge inspection on a UAV platform, quantify its performance for steel corrosion evaluation and concrete delamination detection in …

Thermally-Stable Passive Antenna Sensor For Strain And Crack Monitoring, Dan Li, Yang Wang

INSPIRE-UTC Annual Meetings

An RFID patch antenna sensor can be used to wirelessly measure the strain and/or crack on a structural surface through the shift of its electromagnetic resonance frequency. According to electromagnetic theory, the resonance frequency �_R of a patch antenna has an approximately linear relationship with strain �: [Formula]

Previous design of antenna sensor with Rogers RT/duroid® 5880 substrate is sensitive to temperature change. A new RFID patch antenna sensor with thermally-stable substrate material Rogers RT/duroid® 6202 is designed and tested through both numerical simulation and laboratory experiments. A new RFID chip with much smaller footprint is adopted in the …

Deep Semantic 3d Visual Metric Reconstruction Using Wall-Climbing Robot, Liang Yang, Bing Li, Yong Chang, Jizhong Xiao

INSPIRE-UTC Annual Meetings

This project introduces an inspection method using a deep neural network to detect the crack and spalling defects on concrete structures performed by a wall-climbing robot. First, we create a pixel-level semantic dataset which includes 820 labeled images. Second, we propose an inspection method to obtain 3D metric measurement by using an RGB-D camera-based visual simultaneous localization and mapping (SLAM), which is able to generate pose coupled key-frames with depth information. Therefore, the semantic inspection results can be registered in the concrete structure 3D model for condition assessment and monitoring. Third, we present our new generation wall-climbing robot to perform …

Modeling Hose Dynamics For Unmanned Aerial Vehicles, Blake Hament, Paul Y. Oh, Autonomous Systems Lab (Dasl)

INSPIRE-UTC Annual Meetings

Bridges and other large pieces of infrastructure accumulate massive amounts of dirt, dust, and other particulates that can obscure the structure when scanning to discern structural integrity. Traditionally, these particulates have been removed by humans operating handheld compressed-air hoses, often while mounting ladders -- a risky and inefficient task. To improve infrastructure scanning, unmanned aerial vehicles (UAV) equipped with hoses could be used to clean the structure in place of the current method.

The challenge in equipping a UAV with a hose is compensating for the reaction forces and torques produced by fluids expelled by the hose. In order to …

Parallel Manipulator-Gripper For Mobile Manipulating Uavs, Dongbin Kim, Paul Y. Oh, Autonomous Systems Lab (Dasl)

INSPIRE-UTC Annual Meetings

Unmanned Aerial Vehicles (UAVs) are originally developed for military, but have been developed over time to time for valuable roles in surveillance, work-assistant, and intelligence for both civilian and military operations.

The ability of UAVs that manipulate or carry objects can expand the type of tasks achieved by unmanned aerial systems. High degree of freedom robots with dexterous arm can lead to various applications. Most of manipulators are serial, each motor on each joint affects on stabilizing UAVs. Our lab , DASL , has presented parallel mechanism manipulator for UAVs. It results in less impact on center of gravity(CoG) of …

Integrated Fiber Optic Sensors For Strain, Temperature And Corrosion-Induced Mass Loss Measurement, Chuanrui Guo, Liang Fan, Genda Chen

INSPIRE-UTC Annual Meetings

In this study, a fiber optic sensing system based on long period fiber gratings (LPFG) in LP06 and LP07 modes is designed, fabricated and tested for simultaneous measurements of strain, temperature and corrosion-induced mass loss. It consists of three steel tubes and several Fe-C coated LPFG sensors for long- and short-term corrosion monitoring, respectively, when deployed in proximity and parallel to a steel member. Graphene/silver nanowire (Gr/AgNW) composite was coated on the LPFG surface for efficient Fe-C electroplating due to its high optical transparency and conductivity. The sensor was subjected to both tensile strain and temperature, and submerged in 3.5 …

Bridge Resilience Assessment With Inspire Data, Yijian Albert Zhang, Reginald Desroches, Iris Tien

INSPIRE-UTC Annual Meetings

In this research, we proposed analytical models validated with numerical results to assess how inspection-collected data on corrosion can be used to update bridge models and predict performance under future events. A detailed investigation of the vulnerability of bridges due to corrosion at both component and global levels. The results show the impact of corrosion-induced degradation on the seismic fragility of reinforced concrete columns under various failure modes, e.g., flexural, shear, and lap-spliced failures. As increasing amounts of data are collected on the states of bridges, the results show how these data can be used to update bridge assessments and …

Microwave Imaging For Corroded Rebars And Delamination In Concrete Structures, Matthew Dvorsky, Stephon Barker, Mohammad Tayeb Ahmad Ghasr, R. Zoughi

INSPIRE-UTC Annual Meetings

Corrosion of embedded steel reinforcement bars (rebars) in concrete leads to concrete cracking and delamination, which in turn leads to increased salt and moisture permeation and further damage. This study aims to evaluate the effectiveness of microwave imaging for the characterization of this corrosionand delaminationof steel rebar embedded in concrete.

Hyperspectral Image Analysis For Mechanical And Chemical Properties Of Concrete And Steel Surfaces, Liang Fan, Paul Manley, Huaishuai Shang, Abdullah Alhaj, Hongyan Ma, Genda Chen

INSPIRE-UTC Annual Meetings

According to the 2017 ASCE Report Card, 39% and 15% of 614,387 bridges in the U.S. are more than 50 years and 40 to 49 years, respectively. The number of deficient bridges is increasing. One of the most common causes of reinforced concrete deterioration is corrosion of steel reinforcing bars. Currently, most bridges are visually inspected every two years using boom/snooper trucks to get access to various areas to be inspected. The subjective visual inspection often leads to inconsistent results that are less useful in bridge management. Hyperspectral camera, installed on an unmanned aerial vehicle, can potentially supplement visual inspection …

Uav-Enabled Measurement On Magnetic Field Of Smart Rocks For Bridge Scour Monitoring, Haibin Zhang, Zhaochao Li, Genda Chen

INSPIRE-UTC Annual Meetings

Scour and other hydraulic induced failures accounted for 58% of over 1,500 bridge collapses in the U.S. Bridge scour is the engineering term for the erosion of soil surrounding a bridge foundation as a result of water current. Monitoring with fixed and/or portable instrumentations is one of the most effective measures in mitigating scour hazards. However, fixed instrumentation with sensors installed prior to flood events cannot detect scour other than the area instrumented. It is susceptible to the harsh environment during a flood event. Portable instrumentation is difficult to deploy during a severe flood event due to safety consideration and/or …

Battery-Free Antenna Sensors For Strain And Crack Monitoring Of Bridge Structures, Yang Wang

INSPIRE-UTC Annual Meetings

Fatigue cracks need to be monitored in fatigue critical elements. Previous research by the PI produced a radiofrequency identification (RFID) sensor prototype that can accurately measure tens of micro-strains in laboratory. The antenna sensor was made on a glass microfiber-reinforced polymer substrate. Although accurate for strain measurement and detection of fatigue cracks, the sensor performs less satisfactorily in field conditions since the substrate material (RT/duroid® 5880) is susceptible to thermal effect. In addition, a wireless interrogation distance by a general-purpose commercial RFID reader is limited to the order of meter, which is not desirable with the operation of a UAV. …

Uav-Enabled Measurement For Spatial Magnetic Field Of Smart Rocks In Bridge Scour Monitoring, Genda Chen

INSPIRE-UTC Annual Meetings

Foundation scour is the main cause of bridge collapses in the U.S. In 2011, the principal investigator (PI) proposed smart rocks with embedded magnets for bridge scour monitoring. Once deployed around a bridge pier, smart rocks as field agents offer mission-critical information about the maximum depth of a scour hole developed around the bridge foundation – the key parameter that is used to assess foundation stability in engineering design and retrofit. Smart rocks have recently been deployed and tested at three bridge sites in California and Missouri. With multiple measurements, they can be located with an accuracy of 0.5 m. …

Internet Traffic Forecasting Model Using Self Organizing Map And Support Vector Regression Method, Enrico Laoh, Fakhrul Agustriwan, Chyntia Megawati, Isti Surjandari

Makara Journal of Technology

Internet traffic forecasting is one of important aspect in order to fulfill the customer demand. So, the service quality of internet service provider (ISP) can be maintained at the good level. In this study self-organizing map (SOM) and support vector regression (SVR) algorithm are used as forecasting method. SOM is first used to decompose the whole historical data of traffic internet into clusters, while SVR is used to build a forecasting model in each cluster. This method is used to forecast ISPs traffic internet in Jakarta and surrounding areas. The result of this study shows that SOM-SVR method gives more …

Effects Of The Preheating Temperature On The Crystal Structure And Texture Of Martensitic Stainless Steel, Tri Hardi Priyanto, Rifai Muslih, Herry Mugirahardjo, Bharoto Bharoto, Andon Insani, Muzzakiy Muzzakiy

Makara Journal of Technology

Theoretically, the preheating temperature refers to the start martensite temperature (Ms), and the martensite transformation can be considered as the conservation of the invariant habit-plane in the lattice structure. The habit-plane is the interface plane between austenite and martensite as measured on a macroscopic scale. From the calculation, Ms = 252 °C. The martensite formation can be affected by temperature or stress treatment. In this experiment, temperature treatment was conducted. The sample was treated at 250 °C ± 10 °C. Before and after the pre-heat treatment, the sample was characterized using the neutron diffraction method. BATAN’s Texture Diffractometer (DN2) with …

Investigation Of Ship Hull Girder Strength With Grounding Damage, Muhammad Zubair Muis Alie, Ristiyanto Adiputra

Makara Journal of Technology

The objective of the present study is to investigate ship hull girder strength as a result of grounding damage upon longitudinal bending. A bulk carrier and tanker are analyzed and Smith’s Method is adopted and implemented in the analysis program. An efficient solution procedure is performed by assuming the cross-section remains plane and the vertical bending moment is applied to the cross section. As a fundamental case, the damage is simply created by removing the elements from the cross section. Welding residual stress, initial imperfections, and crack extensions are not considered. The grounding damage is made by two conditions, namely …

Load Distribution Of Adjacent Prestressed Concrete Box Beam Bridges, Luis F. Urrego, Ryan T. Whelchel, Robert J. Frosch, Christopher S. Williams

The Summer Undergraduate Research Fellowship (SURF) Symposium

One of the most common bridge types is the adjacent prestressed concrete box beam bridge because the system is economical and simple to build; over 43,000 are currently in service within the US. However, they are highly susceptible to strand corrosion and concrete deterioration which can result in early loss of load capacity. Therefore, an experimental program sponsored by the Indiana Department of Transportation (INDOT) was initiated to determine the behavior of deteriorated beams and develop recommendations for load rating and design of this bridge type. Displacement sensors were installed on a bridge in service to measure its deformation under …

Satellite-Based Monitoring Of Spatiotemporal Changes In Batudulang Forest In Sumbawa, Indonesia, Mohammad Muslim, Arief Budhi Witarto, Wahyu Indrajaya

Makara Journal of Technology

Space-based earth observation technology applicable to forest inventory and monitoring is well known in the scientific community. High-resolution satellite images form an important data source for forest mapping and change detection at regional and national scales. The value of forest change information derived from remote sensing data is significantly enhanced if this information is integrated into a spatially explicit geographic information system. Satellite-based rapid assessment was conducted to measure spatiotemporal changes in Batudulang forest over the years. The general approach to quantify change in the spatial aspect of the forest involved change detection using moderate-resolution imaging spectro-radiometer satellite-based normalized difference …