Structural Engineering Commons^™

Heavy Timber Buckling-Restrained-Braces, Kaylee Pit, Junning Liu

Architectural Engineering

No abstract provided.

Mechanism Of Tricalcium Silicate Hydration In The Presence Of Polycarboxylate Polymers, Rachel Cook, Hongyan Ma, Aditya Kumar

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Abstract: The early-age hydration of cement is inhibited in the presence of comb-shaped polycarboxylate ether (PCE) polymer -- a dispersant commonly added to control rheological properties of fresh cement paste. This study employs a series of microcalorimetry experiments and phase boundary nucleation and growth simulations to elucidate the effects of dosage and molecular architecture of PCE on hydration of tricalcium silicate (Ca₃SiO₅ or C₃S in cement notation), the dominant phase in cement. Results show that PCE -- regardless of its molecular architecture -- suppresses early-age hydration of C₃S. PCE-induced retardation becomes increasingly more …

Review Of Fiber Optic Sensors For Structural Fire Engineering, Yi Bao, Ying Huang, Matthew S. Hoehler, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Reliable and accurate measurements of temperature and strain in structures subjected to fire can be difficult to obtain using traditional sensing technologies based on electrical signals. Fiber optic sensors, which are based on light signals, solve many of the problems of monitoring structures in high temperature environments; however, they present their own challenges. This paper, which is intended for structural engineers new to fiber optic sensors, reviews various fiber optic sensors that have been used to make measurements in structure fires, including the sensing principles, fabrication, key characteristics, and recently-reported applications. Three categories of fiber optic sensors are reviewed: Grating-based …

Failure Mode Identification Of Masonry Infilled Rc Frames, Rabab Allouzi, Ayhan Irfanoglu

Emirates Journal for Engineering Research

This paper presents a new method to identify the ultimate failure mode of reinforced concrete (RC) frames due to the presence of masonry infill walls. The proposed method is based on simple geometry, reinforcement ratios and material properties of the elements involved in the frame-wall assembly. A simple engineering tool, expressed in terms of infill wall-to-RC frame stiffness and strength ratios, is developed to estimate whether the ultimate failure mode that would evolve during strong earthquake ground shaking in the infilled RC frame is brittle or ductile. The brittle failure mode, that is, shear failure in columns, should be avoided …

Inspire Newsletter Spring 2019, Missouri University Of Science And Technology. Inspire - University Transportation Center

INSPIRE Newsletters

No abstract provided.

Inspire Newsletter Fall 2019, Missouri University Of Science And Technology. Inspire - University Transportation Center

INSPIRE Newsletters

No abstract provided.

Exploring Engineering Club, Samantha Corey, Stephen Yaghmour

Honors Program: Expanded Learning Clubs

Exploring Engineering Club provides an introduction to a variety of engineering problems and piques the students’ interest in engineering by accompanying the information with hands-on problem solving activities mainly related to structural engineering. The activities will often be done in teams which will teach good teamwork skills, as well as problem solving and critical thinking.

Seismic Performance Of Reinforced Concrete Frames Retrofitted Using External Superelastic Shape Memory Alloy Bars, Yamen Ibrahim Elbahy, Maged A. Youssef, Mohamed E. Meshaly

Civil and Environmental Engineering Publications

Pre-1970s designed and built reinforced concrete frame structures are considered unsafe when subjected to seismic loads. Insufficient anchorage of the beam reinforcement in the beam-column joints of these structures is considered a main deficiency. Newly built frame structures are seismically designed for safety, where high inelastic deformations can occur under moderate to strong earthquakes. Minimizing these inelastic deformations makes the structure repairable. One way to minimize these residual deformations is by using smart materials such as superelastic shape memory alloys (SMAs). In this paper, the seismic performance of RC frames retrofitted using external superelastic SMA bars is investigated and compared …

Assessing Impact And Blast Resilience Of Polymer Coated Cementitious Materials, Murtaza Nalwala, Gabriel Nsengiyumva, Yong-Rak Kim

UCARE: Research Products

RESEARCH MOTIVATION The bridge piers are highly vulnerable to the impact and blast loads. The position in which they are constructed makes it difficult to install protective devices around them. By the current AASHTO standard, it is possible to under-design bridge piers for commercial vehicle impacts and other events such as blast.

OBJECTIVE To improve impact and blast resilience of bridge piers using polymeric coatings.

CONCLUSION Polymer coating of Portland cement concrete can be achieved with a good bonding. ü The polymeric coating seem to improve impact resilience of Portland cement concrete by increasing absorbed impact energy (i.e., area underneath …

Enhanced Concrete Bridge Assessment Using Artificial Intelligence And Mixed Reality, Enes Karaaslan

Electronic Theses and Dissertations

Conventional methods for visual assessment of civil infrastructures have certain limitations, such as subjectivity of the collected data, long inspection time, and high cost of labor. Although some new technologies (i.e. robotic techniques) that are currently in practice can collect objective, quantified data, the inspector's own expertise is still critical in many instances since these technologies are not designed to work interactively with human inspector. This study aims to create a smart, human-centered method that offers significant contributions to infrastructure inspection, maintenance, management practice, and safety for the bridge owners. By developing a smart Mixed Reality (MR) framework, which can …

Development Of Poly-Vinyl Alcohol Stabilized Silver Nanofluids For Solar Thermal Applications, James Walshe, George Amarandei, Hind Ahmed, Sarah Mccormack, John Doran

Articles

Nanofluids offer the potential to address the low thermal conductivities found in conventional heat transfer fluids, through their unique electrical, optical and thermal properties, but their implementation remains restricted due to absorption and stability limitations. Here, we characterize and exploit the distinctive plasmonic properties exhibited by polyvinyl-alcohol stabilized silver nanostructures by tuning their absorption and thermal properties through controlling the nanoparticle size, morphology and particle-size distribution configuration at the synthesis stage. The photo-thermal efficiency of different water-based silver nanofluids under a standard AM1.5G weighted solar spectrum were explored, the influence of each of these components on the resulting fluids performance …

Field And Numerical Study For Deteriorating Precast Double-Tee Girder Bridges, Brian Kidd

Electronic Theses and Dissertations

Two deteriorating DT bridges in South Dakota, both over 30-years old, were field tested with a static and dynamic load. From the recorded strain values, the liveload distribution factors (LLDFs) and dynamic load allowance (IM) factors were calculated. The AASHTO LRFD and AASHTO Standard Specifications were compared with the field LLDFs and IMs. It was determined that the AASHTO LRFD Specifications were conservative for deteriorating DT girder bridges, with two exceptions. The AASHTO Standard codified LLDFs were significantly higher than the field LLDFs in all cases. The AASHTO LRFD and AASHTO Standard specifications were conservative when calculating the IM factors …

What Is A Bim Design Model?, James Peters, Malachy Mathews

Conference papers

The recent report into Building Information Management or BIM, by construction law experts May Winfield and Sarah Rock entitled “Winfield Rock Report” [1] gives reason to state that the UK architectural, engineering and construction industry or AEC, is hindered by the absence of a clear definition of Level 2 BIM. The ISO 19650-2 standard published in 2019, is based upon PAS1192-2:2013. The intent of ISO 19650-2 is to provide a road map to facilitate the standardisation of BIM process in a uniformed fashion. A key pillar of ISO 19650 is the “information cycle” and central to this is a federated …

Perceptions Of Vulnerability To Flooding, Hurricanes, And Climate Change On Grand Isle, Louisiana’S Only Inhabited Barrier Island, Lauren Miller

Graduate Student Theses, Dissertations, & Professional Papers

This study used in-depth interviews of permanent residents on Grand Isle, Louisiana, a remote barrier island, to better understand their perceptions of structural flood measures, non-structural responses to flooding and hurricanes, and perceptions of vulnerability to flooding, hurricanes, and climate change on a remote barrier island-Grand Isle, Louisiana. Residents' perceptions regarding the various structural measures implemented by the federal, state, and local government appeared mixed. Non-structural responses to flooding risks implemented at the household, community, state, and federal level continue to strengthen resiliency on Grand Isle. According to interviewees, aspects of environmental, rural, and economic vulnerability on Grand Isle impact …

A Bridge Rehabilitation Strategy Based On The Analysis Of A Dataset Of Bridge Inspections In Co. Cork, Liam Dromey

Masters

Ageing highway structures present a challenge throughout the developed world. The introduction of bridge management systems (BMS) allows bridge owners to assess the condition of their bridge stock and formulate bridge rehabilitation strategies under the constraints of limited budgets and resources. This research presents a decision-support system for bridge owners in the selection of the best strategy for bridge rehabilitation on a highway network. The basis of the research is an available dataset of 1,367 bridge inspection records for County Cork that has been prepared to the Eirspan BMS inspection standard and which includes bridge structure condition ratings and rehabilitation …

Influence Of Pumping Parameters On The Freeze-Thaw And Scaling Resistance Of Highly Workable Concrete, Alexandra Nicole Wehar

Masters Theses

“Over the past 60 years, pumping concrete has gained popularity due to the economic and technical benefits that typically accompanies it. However, boom configuration and flow rate can adversely affect freeze-thaw and scaling resistance of concrete due to the effects of pressure on the air-void system. Therefore, the objective of this research is to assess the influence of different pumping parameters on the durability of hardened self-consolidating concrete. Self-consolidating, flowable, and conventional concrete mixtures were tested during large scale pumping experiments positioning the pump boom in an “A” and a flat shape as well as using different pumping speeds. In …

In Situ Mechanical Characterization Of The Mixed- Mode Fracture Strength Of The Cu/Si Interface For Tsv Structures, Chenglin Wu, Congjie Wei, Yanxiao Li

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In situ nanoindentation experiments have been widely adopted to characterize material behaviors of microelectronic devices. This work introduces the latest developments of nanoindentation experiments in the characterization of nonlinear material properties of 3D integrated microelectronic devices using the through-silicon via (TSV) technique. The elastic, plastic, and interfacial fracture behavior of the copper via and matrix via interface were characterized using small-scale specimens prepared with a focused ion beam (FIB) and nanoindentation experiments. A brittle interfacial fracture was found at the Cu/Si interface under mixed-mode loading with a phase angle ranging from 16.7° to 83.7°. The mixed-mode fracture strengths were extracted …

Incorporation Of Contaminated Sediment Into Environmentally Safe Concrete, Andrew Needs

Williams Honors College, Honors Research Projects

The research performed through this project provided some interesting results on how the different properties of the contaminated sediment can impact the strength of the new concrete.

Average three, seven, and fourteen-day strengths increased when comparing to the baseline mix developed for the experiment. Increases in strengths were notices in the ten and twenty-five percent soil replacement mixes. The largest increase was approximately thirty-three percent greater than the baseline average.

The results from the forty percent replacement test showed a significant decrease in strengths when comparing against the baseline mix. A loss of about thirty percent was observed between the …

Post-Earthquake Assessment And Numerical Modeling Of Freestanding Heritage Structures, M. Khalid Saifullah, Christine E. Wittich

Department of Civil and Environmental Engineering: Faculty Publications

Historic and heritage structures are particularly vulnerable to earthquakes, where damage or collapse can not only lead to loss of a structure but also the loss of irreplaceable heritage. Many heritage structures can be classified as freestanding (detached) structures, including unreinforced masonry walls, classical multi-drum columns, and statue-pedestal systems. However, the seismic response of freestanding structures (sliding, rocking, rock-slide, overturning) is poorly predicted by existing methods due to geometric non-linearities as well as sensitivity to interface conditions and modeling parameters. Previous studies have focused on analytical modeling of simplified systems and/or experimentation under controlled laboratory conditions. In contrast, this paper …

Post-Fire Damage Geospatial Assessment Via Point Clouds Of A Highway Bridge Structure, Yijun Liao, M Ebrahim Mohammadi, Richard L. Wood, Christine E. Wittich

Department of Civil and Environmental Engineering: Faculty Publications

This paper discusses the quantitative post-fire damage assessment of a steel girder bridge via point clouds. In this case study, the point cloud was collected using light detection and ranging (lidar) for a detailed geometric and shape analysis. The out-of-plane deformation was analyzed to locate and quantify buckling across the length of the steel girders.