Structural Engineering Commons^™

Defects Detection Of Concrete Bridge Decks Using Uav-Based Infrared Thermography, H. B. Zhang, Z. Zhou, G. Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Concrete bridges are vulnerable to both natural and man-made disasters, as well as aging and deterioration processes throughout their lifespan. Timely detection of defects in concrete structures is crucial for repair and decision-making purposes. However, traditional methods like visual inspection are time-consuming and expensive. Unmanned aerial vehicles (UAVs) equipped with infrared thermography (IRT) offer an efficient and cost-effective solution for detecting defects in concrete structures. This study presents passive and active IRT techniques for detecting common concrete defects, such as delamination and cracks. Principle and methods for quantifying these defects and evaluating the extent of damage are introduced. Experiments are …

Inspire Newsletter Fall 2024, Missouri University Of Science And Technolgy Inspire - University Transportation Center

INSPIRE Newsletters

No abstract provided.

Miniature 3d Position-To-Optical Displacement Sensor, Genda Chen, Jie Gao, Chuanrui Guo

Patents

A miniature, micrometer-accuracy, three-dimensional (3D) position-to-optical displacement sensor that has at least one extrinsic Fabry-Perot interferometer (EFPI) in Z direction and a series of plasmonic metasurface resonators with distinctive wavelength-selective characteristics in X and Y directions. The interferometer comprises at least one single mode optic fiber for light propagation, and a substrate mirror to create a light interference fringe as a function of distance between the mirror and the distal end of the optic fiber. Each plasmonic resonator is capable of modifying the substrate mirror and comprises an array of multiple unit nanostructure unit cells that are arranged in a …

Three-Dimensional Printing Of Reinforced Concrete And Nozzle Therefor, Chenglin Wu, Genda Chen, Dimitri Feys, Guirong Yan, Bryce Tyler Tafolla

Patents

A three-dimensional printing system for reinforced concrete and a nozzle therefore. The system employs an extruder for extruding unreinforced concrete and a concrete reinforcement feeder is for feeding one or more elongate reinforcement members. The nozzle has an outlet and is operatively connected to the extruder and the concrete reinforcement feeder to receive the unreinforced concrete from the extruder and to receive the one or more elongate reinforcement members from the concrete reinforcement feeder. The nozzle combines the unreinforced concrete from the extruder and the one or more elongate reinforcement members from the concrete reinforcement feeder into a reinforced concrete …

Behavior Of Concrete Mixes Using Recycled Aggregate Confined With Steel Sections, Latifa Sobhi Kassem, Adnan El-Masri, Nour Webhi

BAU Journal - Science and Technology

Recycled Concrete Aggregate (RAC) is a form of recycled concrete that has been studied for green building for the past 50 years. It can be used to create strong structures, such as seismic retrofitting of earthquake-prone structures. Studies have attempted to experimentally study the effect of using recycled aggregate in concrete, but the literature lacks the use of recycled concrete aggregate rapped with steel rings. This study examines the behavior of circular concrete columns with different percentages of recycled aggregate. It examines the behavior of a column with different percentages of recycled aggregate, one without jacketing, one with partial jacketing, …

Effect Of Lime Content, Curing Temperature, And Aging Condition On Low-Alkaline Concrete, Mahdi Parsa Pour, Reza Shaban Sharghi, Faezeh Nejati, Elmira Khaksar Najafi

Makara Journal of Technology

This study determines how curing temperatures, aging condition, and hydrated lime contents affect the unconfined compressive strength (UCS), modulus of elasticity, and workability of low-alkaline concrete. Samples were prepared in two different groups to determine the optimum hydrated lime content and aging conditions to assess the mutual effect of NaOH molarity and curing temperature, that is, 70 °C for 48 h or room temperature, on samples with and without lime. The results showed that the increase in hydrated lime content affected alkali concentration. The samples with lime exhibited a clear peak in UCS (6 M NaOH) compared with the continuous …

Isolation And Characterization Of Caffeine-Degrading Bacteria From Coffee Plantation Areas In Malaysia, Elvina Clarie Dullah, Mohd Fazli Farida Asras

Makara Journal of Technology

Decaffeination by microbial degradation is currently the most optimal and low-cost approach, involving only microbial cells and/or their enzymes. The bacterium was characterized using a series of biochemical tests. Positive results were obtained from carbohydrate fermentation, citrate utilization, and catalase tests, while negative results were obtained from Voges-Proskauer (VP) and indole tests. Three different caffeine concentrations of 0.25%, 0.4%, and 2% were tested and measured through Gas Chromatography-Mass Spectrophotometry (GC-MS) analysis. The highest caffeine reduction (89.25%) was found when 0.25% caffeine was used in the media. Only a small amount of caffeine was reduced to 0.4% and 2%, with 34.78% …

Optimization Of The Building Envelope And Roof Shading To Reduce The Energy Consumption Of College Low-Rise Buildings In Indonesia, Nasruddin Nasruddin, Azimil Gani Alam, Mohammad Imroz Sohel

Makara Journal of Technology

Energy consumption in buildings is a crucial concern globally, prompting researchers to explore innovative solutions to mitigate its impact. This study investigates the optimization of building envelopes and roof shading systems of existing buildings in Indonesia to realize notable energy savings. Multiple scenarios were explored, with modifications to building envelopes and roof shading, highlighting the overall thermal transfer value as a key parameter. Using EnergyPlus simulations, the efficacy of natural ventilation in corridors and roof shading modifications was assessed in reducing energy consumption. The findings revealed that renovating existing buildings by optimization of the building envelope and roof shading by …

Early-Age Strength And Failure Characteristics Of 3d Printable Polymer Concrete: Numerical Modelling And Experimental Testing, Mohammad Amin Dehghani Najvani

Civil Engineering ETDs

The time-dependent rheological and early-age strength parameters of Polymer concrete (PC) were investigated. PC flow decreased, and the static yield stress and thixotropy increased as the specimen aged, while the dynamic yield stress remained unchanged. The study found that the Herschel-Bulkley model can accurately describe the PC’s rheological behavior over time. The change in cohesion strength and internal friction angle over time was observed using uniaxial unconfined compression and direct shear tests of fresh PC. A time-dependent MohrCoulomb failure criterion was established. Temperature analysis was used to determine the gel time and explain the evolution of the time-dependent early-age strength …

Climate Change Impact On Bridge Scour Risk In Ny State: A Gis-Based Risk Analysis Model, Muhammad Hassan Butt

Publications and Research

Bridge scour, the primary cause of bridge failure in the United States, escalates post-severe storms, necessitating effective mitigation. This study employs a GIS-based risk analysis model to assess climate change's impact on bridge scour and associated risks in New York State. Data from the National Bridge Inventory, climate hazard maps, and geospatial data are integrated.

Self-Consolidating Concrete Design For Drilled Shaft Structural Applications, Grady S. Caton

Graduate Theses and Dissertations

Self-consolidating concrete (SCC) is a relatively new concrete technology which allows the concrete to be placed without the need for manual or machine vibration. This innovation reduces labor costs, construction times, and can provide a smooth, finished surface. However, this technology is used in the United States primarily in the precast and prestressed concrete industry. The utility of SCC in structural applications, such as areas of dense reinforcement or locations where complex geometry makes consolidation impossible, is also advantageous. In this study, a series of SCC mixtures were developed both with and without fly ash replacement. These mixtures were then …

Comparing In-Situ Liquefaction Triggering Procedures For Sites In Arkansas, Sagar Barua

Graduate Theses and Dissertations

There currently exists a significant amount of uncertainty when designing piles for bridge foundations in liquefiable soil. Currently ARDOT engineers use a Standard Penetration Test (SPT) based liquefaction spreadsheet developed 10 years ago to evaluate liquefaction triggering. Since this spreadsheet was developed, updates to the liquefaction triggering procedures have been published making the spreadsheet out-of-date. Moreover, additional methods of liquefaction evaluation using cone penetration test (CPT) and shear wave velocity (Vs) provide added means of evaluating liquefaction potential. This thesis updates ARDOT's liquefaction triggering evaluation methodology with the newest procedures and incorporates additional empirical liquefaction hazard estimates such as the …

Improvement Of Rotation Capacity Of Composite Beam-To-Hss Column Connections Using External Horizontal Stiffeners, Mahdi Afshar Arjmand

Master's Theses

Improvement of Rotation Capacity of Composite Beam-to-HSS Column Connections Using External Horizontal Stiffeners

Mahdi Afshar Arjmand

This thesis focuses on the analysis of out-of-plane deformation (OOP) in column flange located in the panel zone of composite beam-to-column steel connection, as a critical aspect of steel structural engineering. This type of connection is an integral component of steel structures, and understanding their behavior is essential for ensuring safety and performance. The investigation involves examining the causes, factors influencing, and potential mitigation strategies for out-of-plane deformation of HSS flange column in these connections. Beam-to-column connections play a vital role in transferring loads …

Bridge Deck Overhang Design: Effective Vehicle Impact Loads, Ultimate Strength, And Implications On Bridge Rail Performance, Andrew Eric Loken

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

When an errant vehicle strikes a bridge railing on a typical girder bridge, impact loads are transmitted downward through the railing and inward through the deck overhang to the primary superstructure elements. In this research effort, design demands for deck overhangs supporting concrete railings were characterized using physical testing and complementary modeling in LS-DYNA. Physical test and modeling results were also used to better characterize the ultimate strength of overhangs supporting post-and-beam railings. Ultimately, a novel design methodology for deck overhangs was developed and proposed for adoption to the AASHTO LRFD Bridge Design Specifications (BDS).

For overhangs with solid concrete …

Structural Performance And Resiliency Of Reinforced Concrete Bridge Pier Columns, Multi-Column Piers, And Bridge Systems Subjected To Multiple Hazards – Fire, Collision, And Air Blast, Qusai Abdulkarim Alomari

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Given their close proximity to traffic and improper employment of protective systems, bridges and bridge piers are vulnerable to multi-hazard events triggered by vehicle collisions coupled with correlated and cascading events, such as explosions and fires. Despite recent catastrophic incidents that have highlighted the profound consequences of these extreme demands, including substantial damage, adverse economic impact, and loss of life, there has been a notable lack of research investigating the performance of bridges and bridge structural components under the aforementioned multi-hazards. Furthermore, current bridge design codes do not address these events assuming that, after these destructive events, replacement of the …

Effect Of Latex Modified Concrete Overlays With Reduced Surface Preparation On The Load Distribution And Flexural Strength Of Channel Girders, Samuel Dodd

All Theses

This thesis investigates the use of a Latex Modified Concrete (LMC) overlay to increase the strength of prestressed channel girders and enhance their ability to distribute load. The research conducted in this thesis involved material testing of several different LMC mixes and flexural testing of an LMC overlay and girder system. The material testing was used to determine a reasonable LMC mix design and surface preparation method to be used for the overlay. Based on material testing it was concluded that a rapid-set mix and pressure washing of the girder surfaces were a reasonable mix design and surface preparation for …

Digital Construction Annual Survey 2022 Report, Davitt Lamon, Ted Mckenna

Reports

The Annual Survey 2022 was conducted to assess the state of digital transformation in the Irish construction and built environment sector. This report presents the analysis of survey data, with a focus on implications for the Build Digital project and Build Digital’s five pillars: Digital Leadership & Cultural Change, Digital Standards, Digital Education & Training, Digital Procurement, and Sustainability & Circular Economy. Key findings from the survey indicated that a significant number of organisations have started their digital transformation journey, with many identifying themselves as proactive and possessing a clear business-focused strategy. However, a considerable cohort of respondents are keen …

International Information Management And Bim Best Practice Report, Ted Mckenna, Davitt Lamon

Reports

In order to inform the Digital Leadership and Cultural Change pillar of the Build Digital, a study of international best practice in digital adoption within the built environment sector globally was undertaken and is presented here-in. In order to identify key learnings for Ireland in the context of digital transformation, eight countries were included in this study, namely, Denmark, Finland, Netherlands, Germany, United Kingdom (UK), New Zealand, Australia and Singapore. These countries were selected for various reasons, including the level of digital maturity, the scale of the built environment sector and geographic spread. Key data for each country is included …

Sustainability And Circular Economy Horizon Scan And Needs Analysis, Sadaf Dalirazar, Mark Kelly, Derek Sinnott, James O'Donnell

Reports

The construction industry plays a crucial role in addressing the climate crisis as it is the largest global consumer of raw materials and contributes significantly to global energy consumption and emissions. Considering the world’s continuous population growth and the imperative to address infrastructure and housing demands the construction sector needs to adopt further sustainable strategies in its activities to reduce the pressure on natural resources. In addition, the Architecture, Engineering, and Construction (AEC) sector is responsible for generating substantial amount of waste known as Construction and Demolition Waste (CDW), which is projected to increase due to the future construction developments. …

Information Management And Bim Standards And Supports Inventory, Ryan Dempsey, Barry Mcauley, David Burke

Tools

The Digital Standards pillar consists of industry experts who champion the benefits of common rules, guidelines, and workflows that facilitate the improvement of information flow and information management across asset life cycles. Digital standards provide a common language that can be translated to technical specifications enabling clients, designers, contractors, and facilities managers, irrespective of their preferred tools, to communicate efficiently and reduce cost, rework, and disputes. Working closely with the Digital Procurement and Digital Education and Training pillars, this pillar is developing and delivering Irish Information Management/BIM (Digital Construction) guidelines for the sector.

This report summarises existing digital construction standards, …