Sessions & Events

 

All sessions and events take place in Central Daylight Time: CDT (UTC-5). On-demand sessions will be available for viewing in the convention platform under "On-Demand Content" within 24-48 hours of the session premiere. Please note, on-demand sessions are not available for CEU credit. * Denotes on-demand content.

H=Hyatt Regency Dallas; U=Union Station

Emerging Methods for Surface Damage Monitoring and Imaging, Part 2 of 2

Wednesday, October 26, 2022  8:30 AM - 10:30 AM, H-Reunion A

The objective of these sessions is to present and discuss different methods for detection and monitoring of surface damage in concrete elements. The focus is how to use SHM techniques to obtain useful information regarding formation and progression of surface damage. These sessions will be of interest to engineers, researchers, and infrastructure owners and operators.
Learning Objectives:
(1) Discuss the use tomography based sensors for structural monitoring;
(2) Review 'big data' analysis techniques and data fusion applications for NDE and SHM methods;
(3) Explain how to use imaging techniques for condition assessment of concrete structures;
(4) Define new sensors and applications for surface damage monitoring and imaging.

This session has been AIA/ICC approved for 2 CEU/PDH credits.


Topology Optimization Enhances the Distinguishability and Reconstructability of Electrical Resistance Tomography Based Sensors

Presented By: Mohammad Pour-Ghaz
Affiliation: North Carolina State University
Description: In the majority of applications of electrical resistance tomography (ERT) the estimation problem consists of either the estimation of spatial conductivity change over an existing background or the estimation of spatial distribution of conductivity of the entire target, including the background. In some instances however, it is possible to design the background conductivity; an example of such application is the design of ERT-based sensors where the background conductivity can be engineered. In such applications the natural question is whether the background conductivity can be engineered in such a way to increase the distinguishability and further reconstructability of the sensor. The present paper, uses topology optimization to design the background conductivity to achieve optimal distinguishability. Then, ERT reconstructions suggest the enhancements of reconstructability using topology optimized sensor.


Challenges with Monitoring Surface and Subsurface Changes in Concrete Due in ASR

Presented By: Paul Noyce
Affiliation: Echem Consultants LLC
Description: Alkali Silica Reactions (ASR) is a harmful long-term deterioration phenomenon for concrete structures. Monitoring and assessing ASR-affected concrete is a challenging task due to the multiscale nature of the damage propagation. The reaction starts at the elementary level by forming gels that swell and induce cracks, eventually affecting the structure's capacity. A combination of subsurface and surface monitoring techniques can provide an effective solution. A field application of coda wave interferometry (CWI) and non-contact visual technique will be discussed in this presentation. CWI monitoring utilizes the sensitivity of the Coda of repeated transmission measurements to changes in stress, temperature, moisture, as well as localized or distributed damage that should be suitable for monitoring the subsurface condition of ASR-affected concrete. The non-contact visual technique includes capturing and analyzing a sequence of photos of the area(s) of interest to identify surface-level changes in the structure. Preliminary results from implementing this methodology on a historic stadium in the United States will be presented.


Case Studies of Data Fusion of Nondestructive Testing and Photogrammetry for Concrete Condition Imaging and Assessment

Presented By: Marisol Tsui-Chang
Affiliation: Olson Engineering, Inc
Description: Visual inspection is often one of the first steps in any concrete condition assessment study. For complex projects, a condition map or sketch is prepared by the engineer. On this map, the observed surface defects, such as cracks and spalls, are manually recorded. As a novel tool for visual inspection, the photogrammetric method uses motion algorithms to create orthomosaic models from overlapping images. As a standalone visual inspection technique, the photogrammetric method is useful for element time lapse analyses and structural health monitoring, as the shape and dimensions of defects (such as cracking) can be quantitatively evaluated and monitored over time. An advantage of the photogrammetric method is its ability to create dimensionally accurate images over which gridded and plotted Non-Destructive Testing (NDT) data can be displayed. This synthesis of data is also known as data fusion. The implementation of data fusion can link the anomalies from the NDT inspection to the surface defects from photogrammetry. Recently, data fusion has been increasingly adopted by engineers and owners so to achieve a more complete concrete condition assessment. A series of condition assessment case studies where data fusion was implemented for different NDT methods (ground penetrating radar (GPR), impact echo/impact echo scanning (IE/IES) and spectral analyses of surface waves (SASW)) is presented in this work.


Surface Damage Imaging for Input to Load Rating of Bridges

Presented By: Paul Ziehl
Affiliation: University of South Carolina
Description: This talk will be focused on a tailored application for imaging based on the platform of aerial drones. The imaging in this case requires relatively precise information on the geometry of surface cracking to provide technical input to the load rating process for a family of bridges in South Carolina that frequently do not meet their load rating criteria (referred to a precast reinforced flat slab bridges).


Study on Traffic Disruption-free Bridge Deck Evaluation and Imaging for Large-scale Stream Data

Presented By: Suyun Ham
Affiliation: University of Texas at Arlington
Description:

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