Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 6 of 6
Full-Text Articles in Engineering
Nonlinear Impact-Echo Test For Quantitative Evaluation Of Asr Damage In Concrete, Clayton Malone, Hongbin Sun, Jinying Zhu
Nonlinear Impact-Echo Test For Quantitative Evaluation Of Asr Damage In Concrete, Clayton Malone, Hongbin Sun, Jinying Zhu
Department of Civil and Environmental Engineering: Faculty Publications
Nonlinear acoustic methods demonstrate high sensitivity for concrete damage evaluation. Among these methods, nonlinear resonance acoustic methods have been widely used in laboratory tests on small scale test samples. In this study, a nonlinear impact-echo (IE) method was proposed for concrete damage evaluation, in which the IE frequency shift was measured at different impact force levels. The nonlinear IE test is similar to the nonlinear impact resonance acoustic spectroscopy (NIRAS) test in the experimental setup and analysis method. How- ever, the nonlinear IE test excites a local thickness resonance mode of a member instead of the global resonance vibration. Therefore, …
Applications Of Stretching Technique And Time Window Effects On Ultrasonic Velocity Monitoring In Concrete, Bibo Zhong, Jinying Zhu
Applications Of Stretching Technique And Time Window Effects On Ultrasonic Velocity Monitoring In Concrete, Bibo Zhong, Jinying Zhu
Department of Civil and Environmental Engineering: Faculty Publications
Coda wave interferometry (CWI) has been used to measure the relative wave-velocity change (dV/V) caused by small changes in materials. This study uses the stretching processing technique which has been used for CWI analysis to investigate velocity changes of direct longitudinal (P) wave, direct shear (S) wave, and coda wave in concrete by choosing different time windows of ultrasonic signals. It is found that the obtained wave-velocity change depends on the time window position, because the relative contribution of P wave and S wave is different in each signal window. This paper presents three experimental scenarios of velocity …
Assessing The Effectiveness Of Problem-Based Learning Across Two Concrete Construction Courses, Anthony Torres, Jiong Hu, Vedaraman Sriraman, Araceli Martínez-Ortiz, Jorge Membrillo-Hernández
Assessing The Effectiveness Of Problem-Based Learning Across Two Concrete Construction Courses, Anthony Torres, Jiong Hu, Vedaraman Sriraman, Araceli Martínez-Ortiz, Jorge Membrillo-Hernández
Department of Civil and Environmental Engineering: Faculty Publications
The goal of this study is to assess the effectiveness of a Problem-Based Learning (PBL) pedagogy that was implemented in two different concrete construction courses. Both courses are a part of an industry focused four-year undergraduate concrete degree program. One of the classes focused on concrete problems, diagnosis, and repair of existing concrete, while the other class focused on handling and management methods of various concrete mixtures. In both courses, a PBL pedagogy was implemented such that students were self-learning and discovering the knowledge through an action-research case study. The action-research case study was specific to the course outcomes relevant …
Applications Of Stretching Technique And Time Window Effects On Ultrasonic Velocity Monitoring In Concrete, Bibo Zhong, Jinying Zhu
Applications Of Stretching Technique And Time Window Effects On Ultrasonic Velocity Monitoring In Concrete, Bibo Zhong, Jinying Zhu
Department of Civil and Environmental Engineering: Faculty Publications
Coda wave interferometry (CWI) has been used to measure the relative wave-velocity change (dV/V) caused by small changes in materials. This study uses the stretching processing technique which has been used for CWI analysis to investigate velocity changes of direct longitudinal (P) wave, direct shear (S) wave, and coda wave in concrete by choosing different time windows of ultrasonic signals. It is found that the obtained wave-velocity change depends on the time window position, because the relative contribution of P wave and S wave is different in each signal window. This paper presents three experimental scenarios of velocity …
Multi-Sensor Data Collection And Fusion Using Autoencoders In Condition Evaluation Of Concrete Bridge Decks, Sepehr Pashoutani, Jinying Zhu, Chungwook Sim, Kwanghee Won, Brian A. Mazzeo, W Spencer Guthrie
Multi-Sensor Data Collection And Fusion Using Autoencoders In Condition Evaluation Of Concrete Bridge Decks, Sepehr Pashoutani, Jinying Zhu, Chungwook Sim, Kwanghee Won, Brian A. Mazzeo, W Spencer Guthrie
Department of Civil and Environmental Engineering: Faculty Publications
This paper presents a multi-sensor data collection and data fusion procedure for nondestructive evaluation/testing (NDE/NDT) of a concrete bridge deck. Three NDE technologies, vertical electrical impedance (VEI), ground-penetrating radar (GPR), and high-definition imaging (HDI) for surface crack detection, were deployed on the bridge deck. A neural network autoencoder was trained to quantify the relationship between VEI and GPR results using the data collected at common positions. This relationship was then used for fusion of VEI and GPR data to increase the reliability and spatial resolution of the NDE measurements and to generate a data-fused condition map that showed novel characteristics. …
Fungi: A Neglected Candidate For The Application Of Self-Healing Concrete, Congrui Jin, Rui Yu, Zhonghe Shui
Fungi: A Neglected Candidate For The Application Of Self-Healing Concrete, Congrui Jin, Rui Yu, Zhonghe Shui
Department of Civil and Environmental Engineering: Faculty Publications
Self-healing mechanism in concrete has been so far achieved mainly by three approaches: autogenous healing, encapsulation of polymeric material, and biologically induced mineralization of calcium carbonate. The microbial approach prevails over the other two approaches due to the high compatibility between the filler material and the concrete compositions. Although the term “microbe” refers to many different types of organisms, research work on self-healing concrete has been so far restricted to bacteria. In this perspective article, we review the current status of bacteria-mediated self-healing concrete and summarize the prospects for future advances. In particular, we point out that fungi may have …