Architecture Commons^™

Rilem Tc 266-Mrp: Round-Robin Rheological Tests On High Performance Mortar And Concrete With Adapted Rheology—A Comprehensive Flow Curve Analysis, Dimitri Feys, Helena Keller, Khadija El Cheikh, Egor Secrieru, Yannick Vanhove

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A comprehensive testing program was carried out to compare the rheological properties of flowable concrete that can be obtained from different rheometers. The results obtained from seven rheometers using vane or similar geometries are discussed. A comprehensive flow curve analysis is undertaken for further comparison of the various rheometers. Partially, large differences could be observed between the results obtained from the different rheometers. However, the device-specific trendlines are shown to have significant correlations with the overall baseline. Two potential causes of differences between results are highlighted: imposition/registration of torque/rotational velocity and discrepancies between the measured material flow behavior in the …

Predicting The Friction Coefficient Of High-Friction Surface Treatment Application Aggregates Using The Aggregates' Characteristics, Ahmed S. El-Ashwah, Korrenn Broaddus, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Providing Sufficient Pavement Surface Friction (I.e., Skid Resistance) between Vehicle Tires and Pavement Surface throughout the Pavement Service Life is Considered to Be One of the Main Objectives of Highway Design. Moreover, Vehicle Safety, the Amount of Consumed Fuel, and the Wearing Rate of Vehicle Tires Generally Are Influenced by Pavement Surface Friction. in This Study, a Comprehensive Experimental Testing Program Was Conducted on Different Aggregate Sources, Including Calcined Bauxite and Five Alternative Local Sources, to Assess their Friction Characteristics. the Testing Program Included a British Pendulum Tester (BPT) and a Dynamic Friction Tester (DFT), Which Were Used to Evaluate …

Rilem Tc 266-Mrp: Round-Robin Rheological Tests On High Performance Mortar And Concrete With Adapted Rheology—Rheometers, Mixtures And Procedures, Dimitri Feys, Mohammed Sonebi, Sofiane Amziane, Chafika Djelal, Khadija El-Cheikh, Shirin Fataei, Markus Greim, Irina Ivanova, Helena Keller, Kamal Khayat, Laurent Libessart, Viktor Mechtcherine, Ivan Navarrete, Arnaud Perrot

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Recent developments in understanding the rheology of mortar and concrete as well as applying this understanding in the practice of construction necessitate an accurate assessment of materials' rheological properties. It is well known that different rheometers for mortar and concrete deliver different results, as this was shown over 15 years ago in two measuring campaigns comparing concrete rheometers. Considering newly developed rheometers, including those to evaluate interface rheology and structural build-up at rest, as well as additional measurement procedures and data interpretation techniques, a new comparison campaign was carried out in 2018 at the Université d'Artois, in Bethune, France. This …

Characterizing Energy Dissipation Of Shallow-Water Wave Breaking In A Storm Surge, Hunter Boswell, Guirong Grace Yan, Wouter Mostert

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

While understanding breaking waves is crucial for the development of parametrizations used in ocean wave modeling for both deep and shallow water, the complete process of wave breaking is not well understood. Here we present direct numerical simulations of two-dimensional solitary waves that shoal and break on a uniform beach in shallow water, with the presence of storm surge represented by an inshore region. The storm surge depth, beach slope, and wave amplitude are varied to study the dependence of energy dissipation in the breaker on wave and bathymetric parameters. We classify wave breaker types and find a separation between …

The Bridge Newsletter Spring 2023, Missouri University Of Science And Technology

The Bridge Newsletter

-Virtual reality in architectural engineering
-Steel Bridge team wins fifth consecutive competition
-S&T Volleyball star ‘jumps’ at research opportunity
-Benavides legacy continues

A Unified Two Independent Stress Variable Approach To Moisture-Change-Induced Unsaturated Soil Volume Change, Sandra Houston, Xiong Zhang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In 1968, Matyas and Radhakrishna introduced the concept of the state surface, demonstrating that unsaturated soil volume change is dependent on two independent stress state variables, net total stress and suction. For decades the basic theory of unsaturated soils has been known, and a holistic view of the elastoplastic response of unsaturated soils, based on a modified state surface approach (MSSA), makes it clear that a method accounting for independent roles of net total stress and suction is required to quantify volume change of unsaturated soils. Still, reliance on pre-unsaturated-soil-mechanics-era methods persists, particularly within the geotechnical practice community. Unsaturated soil …

Calibration Of Bbm Parameters Using The Modified State Surface Approach, Xiong Zhang, Beshoy Riad, Eduardo E. Alonso

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Barcelona Basic Model (BBM) developed by Alonso et al. [1] is the first and the mostwidely used elasto-plastic model for unsaturated soils. The BBM successfully explained many key features of unsaturated soils and received extensive acceptance. However, there is lack of a well-establishedmethod for selecting parameter values for the BBM from laboratory tests, although a variety of methods have been recently developed for calibrating model parameters for the BBM. Concerns still exist on the correctness and robustness of such parameter value selection procedures. The above statements were evidenced by a recent benchmark exercise on selection of parameter values for …

Lunar In-Situ Aluminum Production Through Molten Salt Electrolysis (Lisap-Mse), Jacob Ortega, Jeffrey D. Smith, Fateme Rezaei, David Bayless, William P. Schonberg, Daniel S. Stutts, Daoru Frank Han

NASA-Missouri Space Grant Consortium

The goal of Artemis is to establish a sustained presence on the Moon. To achieve so, numerous resources are necessary. The Moon contains several essential elements needed to sustain human presence. Most of those elements are trapped in the form of minerals. To refine those minerals into useful materials, reduction methods are needed. Most reduction methods on Earth require large amounts of mass and power which is unrealistic for early stages of building a lunar base. To solve this problem, we are developing a concept of Lunar In-Situ Aluminum Production through Molten Salt Electrolysis (LISAP-MSE).

The LISAP-MSE project, if successful, …

Fatigue Behavior And Calculation Methods Of High Strength Steel Fiber Reinforced Concrete Beam, Zhiqiang Gu, Hu Feng, Danying Gao, Jun Zhao, Congjie Wei, Chenglin Wu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Adding Steel Fibers into Concrete Was Considered as One of the Most Effective Ways to Restrain the Crack Development and Improve the Stiffness for Reinforced Concrete (RC) Structures. to Explore the Reinforcement Mechanism of Steel Fibers on the Fatigue Behavior of High-Strength RC Beam, Eight High-Strength Steel Fiber Reinforced Concrete (HSSFRC) Beams Subjected to Fatigue Loading Were Tested in This Study. the Main Design Parameters Considered in This Work Were Stress Level and Steel Fiber Content. the Failure Mode, Crack Patterns, Fatigue Life, Crack Width, and Stiffness Degradation of HSSFRC Beams under Fatigue Loading Were Discussed. the Results Showed that …

Closure To "Some Insights On Flow Over Sharp-Crested Weirs Using Computational Fluid Dynamics: Implications For Enhanced Flow Measurement", Joseph M. Sinclair, S. Karan Venayagamoorthy, Timothy K. Gates

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.

Efficient Recycling Of Waste Rubber In A Sustainable Fiber-Reinforced Mortar And Its Damping And Energy Dissipation Capacity, Haodao Li, Wu Jian Long, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A Great Number of Waste Tires Are Discarded in Landfills, Occupying Land Resources, and Severely Endangering the Ecosystem. Upcycling These Wastes as Aggregates to Partially Substitute Natural Sand and Develop Structure-Function Integration in Concrete Structures is a Desirable Solution. in This Study, a Sustainable Fiber-Reinforced Rubberized Mortar with Superior Material Damping and Moderate Strength is Developed by Combined Use of Waste Crumb Rubber (WCR) Incorporated at 0, 30%, and 60%, by Volume of Sand, and Polyvinyl Alcohol (PVA) Fiber Added at 0, 0.5%, and 1%, by Volume, in a High-Volume Fly Ash Binder System. Low-Temperature Plasma (LTP) Pre-Treatment of the …

Discrete-Element Modeling Of Shear-Induced Particle Migration During Concrete Pipe Flow: Effect Of Size Distribution And Concentration Of Aggregate On Formation Of Lubrication Layer, Tooran Tavangar, Masoud Hosseinpoor, Jeffrey S. Marshall, Ammar Yahia, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Paper Seeks to Better Understand the Particulate Mechanics Giving Rise to the Lubrication Layer (LL) in Flows with Wide Particle-Size Distributions (PSD) Typical of Concrete Pumping Applications. the Study Uses a Soft-Sphere Discrete Element Method (DEM) to Simulate the Shear-Induced Particle Migration (SIPM) Mechanism of Formation of the LL. to Provide Realistic Understanding of SIPM and Rheological Heterogeneity of Concrete, Three Wide PSDs (Fine, Medium, and Coarse) and Three Different Concentrations (10 %–40 %) of Five Spherical-Particle Subclasses (1–17 Mm Diameter) Were Investigated. the Radial Evolution of Concentration and Particle Distribution Was Simulated over Time and the LL Formation …

Analysis Of Eccentrically Loaded Frp Partially Wrapped Reinforced Concrete Columns Subjected To Combined Environmental Erosion, Zhiqiang Gu, Congjie Wei, Chenglin Wu, Danying Gao, Peibo You, Dong Wei

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Behavior of Eccentrically Loaded Fiber Reinforced Polymer (FRP) Partially Wrapped Reinforced Concrete (RC) Columns under Combined Environmental Erosion Was Investigated in This Paper. Circular RC Columns Were Firstly Subjected to Chloride Erosion Where the Target Corrosion Degree (0, 10 %, and 20 %) is Obtained with Externally Applied Current. This Was Then Followed by Partially Strengthening with 2-Ply of Glass Fiber Reinforced Polymer (GFRP) Strips as Well as 50 Freeze–thaw Cycles. Series of Eccentric Compression Tests Were Conducted with Ranging Eccentricities of 0, 5 Mm, 10 Mm, and 15 Mm. for Comparison, the Carbon Fiber Reinforced Polymer (CFRP) Partially …

Performance Assessment Of Bioasphalt Mixtures Containing Guayule Resin As An Innovative Biobased Asphalt Alternative, Ahmed Hemida, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Guayule resin was investigated through mixture to assess its role in the field performance. For performance comparisons, conventional asphalt, neat guayule, asphalt-rubber-guayule, and guayule-rubber binders were implied. Field-simulated lab mixtures were made to investigate the major distresses. Modified Lottman, rut, semicircular bending, and disk-shaped compact tension tests were used to assess stripping, rutting, fatigue, and thermal cracking resistances. Stripping and rutting susceptibilities were also assessed by Hamburg wheel-tracking test. The outcomes disclosed that when the modified Lottman test was used, guayule containing a 7% air content was more susceptible to stripping than that containing a 3.5% air content, resulting in …

Investigation Of Corrosion Mechanism Of Ribbed Mild Steel Bars Coated With Magnesium Potassium Phosphate Cement Paste, Fan Zhang, John J. Myers, Wenyu Liao, Cun Hui, Hongyan Ma

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This Study Investigated the Anti-Corrosion Performance of Magnesium Potassium Phosphate Cement (MKPC) Paste Applied to the Surface of Ribbed Mild Steel Bars – Which Was Exposed to Simulated Accelerated Corrosive Environment. Four Electrochemical Approaches Were Used Including Open-Circuit Potential (OCP), Electrochemical Impedance Spectroscope (EIS), Polarization Resistance (PR) and Potentiodynamic Polarization (PDP) over a Period of 5376 H (224 Days). Moreover, Visual Inspection, Optical Microscope, and Scanning Electron Microscopy (SEM) with Energy Dispersive Spectroscopy (EDS) Were Used to Assess the Extent of Corrosion on the Samples. to Understand the Mechanism of Corrosion Protection of the Coating System, X-Ray Photoelectron Spectroscopy (XPS) …

Raveling Performance Of Conventional And Rubberized Chip Seal Under Field And Laboratory Traffic Loading, Alireza Pourhassan, Ahmed A. Gheni, Mohamed Elgawady

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Raveling, or the Loss of Surface Aggregate, is a Major Concern in Chip Seal Pavement. Previous Studies Have Used the Standard Sweep, Vialit, and Pennsylvania Tests to Evaluate Raveling, But These Tests Do Not Replicate the Stresses of Rolling Vehicle Tires on Chip Seal and Have Produced Inconsistent Results. Additionally, These Tests Mainly Evaluate Early-Stage Raveling Due to their Short Curing Time. in This Study, a Small-Wheel Traffic Simulation Device (SWTS) Was Used to Apply Similar Stresses as Rolling Vehicle Tires and Produce Comparable Raveling Results. This Was Confirmed through a 13-Month Field Observation of Chip Seal, Where the Laboratory …

Photolysis Of 3-Nitro-1,2,4-Triazol-5-One: Mechanisms And Products, Hunter W. Schroer, Esteban Londono, Xueshu Li, Hans Joachim Lehmler, William Arnold, Craig L. Just

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Insensitive munitions formulations that include 3-nitro-1,2,4-triazol-5-one (NTO) are replacing traditional explosive compounds. While these new formulations have superior safety characteristics, the compounds have greater environmental mobility, raising concern over potential contamination and cleanup of training and manufacturing facilities. Here, we examine the mechanisms and products of NTO photolysis in simulated sunlight to further inform NTO degradation in sunlit surface waters. We demonstrate that NTO produces singlet oxygen, and that dissolved oxygen increases the NTO photolysis rate in deionized water. The rate of NTO photolysis is independent of concentration and decreases slightly in the presence of Suwannee River Natural Organic Matter. …

Hyperspectral Reflectance For Determination Of Steel Rebar Corrosion And Cl− Concentration, Pengfei Ma, Liang Fan, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In This Study, a New Method is Proposed to Determine Chloride Ion (Cl−) Concentration and Steel Rebar Corrosion from Hyperspectral Spectroscopy. Three Groups of Mortar Cubes with Water-To-Cement (W/c) Ratios of 0.5, 0.6, and 0.7 Were Subjected to Rapid Corrosion Testing in 3.5 Wt% NaCl Solution to Accelerate the Transport of Chloride Ions. Embedded Along the Centerline of Each Mortar Cube Was a Steel Rebar that Corroded When the Cl− Accumulation Around It Exceeded a Critical/threshold Concentration. Open Circuit Potential Was Measured to Characterize the Corrosion Possibility of Steel Rebar. Mortar Surfaces Were Scanned with a Hyperspectral Camera in the …

Enhancement Of Heat-Cured Cement Paste With Tannic Acid, Jinrui Zhang, Ziye Kang, Youzhi Yang, Biqin Dong, Hongyan Ma

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Improvement of Cement-Based Materials' Performance by Natural Organic Compounds Can Greatly Promote the Green and Sustainable Development of the Construction Industry. However, Such Compounds Are Not Widely Used Yet Because of their Retarding Effect on Cement. in This Study, the Retardation Effect of Tannic Acid (TA, a Well-Known Retarding Compound) is overcome and the Enhancing Effect is Achieved by Adding Less Than 0.1% Content and Curing Samples in Thermal Regime. Then the Mechanism of TA Enhancing Heat-Cured Cement Pastes is Studied Systematically. Mechanical Properties Results Suggest that Addition of 0.025% TA Can Reduce the Compressive and Flexural Strengths of …

Integrating Quality Assurance In Balance Mix Designs For Durable Asphalt Mixtures: State-Of-The-Art Literature Review, Yizhuang David Wang, Jun Liu, Jenny Liu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Delivering durable asphalt concrete within a reasonable cost is one of the great ambitions of pavement material engineers. This state-of-the-art review article documents the efforts spent in the past two decades to ensure the durability and performance of asphalt mixtures in mix design and production. A perspective with the attempt to integrate laboratory mix design, plant production quality assurance, and field place acceptance is applied in the review. The development of the performance specification and performance mix design is summarized. The paper categorizes performance specification into index-based performance specification and predictive performance specification that include performance-related specification and performance-based specification. …

Wind Effects On Dome Structures And Evaluation Of Cfd Simulations Through Wind Tunnel Testing, Tiantian Li, Hongya Qu, Yi Zhao, Ryan Honerkamp, Guirong Grace Yan, Arindam Chowdhury, Ioannis Zisis

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In the Study, a Series of Wind Tunnel Tests Were Conducted to Investigate Wind Effects Acting on Dome Structures (1/60 Scale) Induced by Straight-Line Winds at a Reynolds Number in the Order of 106. Computational Fluid Dynamics (CFD) Simulations Were Performed as Well, Including a Large Eddy Simulation (LES) and Reynolds-Averaged Navier–Stokes (RANS) Simulation, and their Performances Were Validated by a Comparison with the Wind Tunnel Testing Data. It is Concluded that Wind Loads Generally Increase with Upstream Wind Velocities, and They Are Reduced over Suburban Terrain Due to Ground Friction. the Maximum Positive Pressure Normally Occurs Near the Base …

Synergistic Effect Of Hedp.4na And Different Induced Pouring Angles On Mechanical Properties Of Fiber-Reinforced Alkali-Activated Slag Composites, Jingjie Wei, Jianwei Liu, Kamal Khayat, Wu Jian Long

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Poor Flexural and Damping Properties of Building Materials Damages Concrete Structures and Affects their Service Life When Concrete Structures Are Subjected to Dynamic Loads. Three Different Dosages (I.e., 0%, 0.3%, and 0.6%) of Organic Phosphonates (HEDP.4Na) and Different Pouring Methods (I.e., Conventional Pouring Method, 90°-Induced Pouring Method, and 150°-Induced Pouring Method) Were Designed to Improve the Flexural and Damping Performance of Fiber-Reinforced Alkali-Activated Slag Composites (FR-AASC). the Enhanced Mechanism of HEDP.4Na Was Revealed by Phase Analysis (X-Ray Diffraction, XRD), Pore Structure Analysis (Mercury Intrusion Porosimetry, MIP), the Heat of Hydration, and Scanning Electron Microscopy (SEM) Analysis. the Results Showed …

Effect Of Class C And Class F Fly Ash On Early-Age And Mature-Age Properties Of Calcium Sulfoaluminate Cement Paste, Sukanta K. Mondal, Carrie Clinton, Hongyan Ma, Aditya Kumar, Monday Uchenna Okoronkwo

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

To Promote the Sustainable Development of Eco-Efficient Calcium Sulfoaluminate (CSA) Cements through the Partial Replacement of the CSA Clinker with Supplementary Cementitious Waste Products, the Effects of Coal Fly Ashes on the Early-Age and Mature-Age Properties of a Calcium Sulfoaluminate (CSA)-Based Cement Paste Were Investigated. the Impacts of Both Class C and Class F Fly Ashes on the Rheological Properties, Hydration Kinetics, and Compressive Strength Development of CSA Cement Paste Were Studied. Rheology-Based Workability Parameters, Representing the Rate of Loss of Flowability, the Rate of Hardening, and the Placement Limit, Were Characterized for the Pastes Prepared with Fixed Water-To-Cement (W/c) …

Rheological Characterization Of Ultra-High Performance Concrete For 3d Printing, Arun R. Arunothayan, Behzad Nematollahi, Kamal Khayat, Akilesh Ramesh, Jay G. Sanjayan

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The authors recently developed a 3D-printable ultra-high performance fiber-reinforced concrete (3DP-UHPFRC) for additive construction of structural members with significantly reduced reliance on steel bars. This study investigates the rheological behavior of the developed 3DP-UHPFRC. The effects of two major factors affecting the performance of 3DP-UHPFRC, namely steel fiber volume (0, 1%, and 2%) and nano-clay (NC) content (0, 0.1%, and 0.2% by binder mass) on workability, static yield stress, dynamic yield stress, and apparent viscosity were determined. Test results showed that the inclusion of steel fibers and NC reduced the workability and led to a significant increase in the static …

Effect Of Additional Water Or Superplasticizer On Key Characteristics Of Cement Paste Made With Superabsorbent Polymer And Other Shrinkage Mitigating Materials, Kamran Aghaee, Ricarda Sposito, Karl Christian Thienel, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The use of superabsorbent polymer (SAP) coupled with expansive agent (EA) or shrinkage-reducing admixture (SRA) can effectively reduce shrinkage of cement-based materials. However, SAP particles at high contents can adversely affect rheological and mechanical properties. Securing proper workability can be accomplished by additional water or adjusting the superplasticizer (SP) demand. There is an uncertainty about the efficiency of these approaches to workability compensation. This study evaluates the effect of additional water or SP on key properties of cement paste made with SAP and relatively high content of EA or SRA. Macro and micro mechanisms underlying the effect of combined shrinkage …

Homogeneous Flow Performance Of Steel-Fiber Reinforced Self-Consolidating Concrete For Repair Application: A Biphasic Approach, Naimeh Nouri, Masoud Hosseinpoor, Ammar Yahia, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this study, fiber-reinforced self-consolidating concrete (FR-SCC) was considered as a diphasic suspension of fiber and coarse aggregate (F-A ≥ 5 mm) skeleton in mortar suspension with solid particles finer than 5 mm. The coupled effect of the volumetric content of fibers, coarse aggregate particle-size distribution, and rheological properties of the mortar on the passing ability and dynamic stability of various FR-SCC mixtures was investigated. Nine high-strength and 10 conventional-strength FR-SCC mixtures for repair application were proportioned with water-to-binder ratios (W/B) of 0.35 and 0.42, respectively, and macro steel fibers of 0.1%–0.5% volumetric contents. The dosages of high-range water-reducer (HRWR) …

Nucleotide Detection Mechanism And Comparison Based On Low-Dimensional Materials: A Review, M. Mustafa Azeem, Muhammad Shafa, Muhammad Aamir, Muhammad Zubair, Basma Souayeh, Mir Waqas Alam

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The recent pandemic has led to the fabrication of new nucleic acid sensors that can detect infinitesimal limits immediately and effectively. Therefore, various techniques have been demonstrated using low-dimensional materials that exhibit ultrahigh detection and accuracy. Numerous detection approaches have been reported, and new methods for impulse sensing are being explored. All ongoing research converges at one unique point, that is, an impetus: the enhanced limit of detection of sensors. There are several reviews on the detection of viruses and other proteins related to disease control point of care; however, to the best of our knowledge, none summarizes the various …

An Insight Into The Effect Of Sharp And Round Edges On The Flow Field-A Cfd Simulation, Abid Hussain, Gao Puzhen, M. Mustafa Azeem, Muhammad Zubair, Muhammad Aamir, Muhammad Irfan Khaleed

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents a numerical investigation of pressure drop and distribution in a channel around a sharp edge and a disc that is connected to the base of a circular rod. We have employed computational fluid dynamics (CFD)-Fluent for the validation of our models. It was found that the edge sharpness of the disc influences the pressure drop., i.e. sharp edge has higher turbulence and pressure drop. We also observed that pressure drops in the case of the circular disc are less than that of the sharp edge. However, pressure drop has essentially the same values for both shapes after …

Analytical And Numerical Behavior Of Double Composite Steel Bridges, Emad M. Hassan, Hussam Mahmoud

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Steel plate girders are considered a viable solution for the construction of medium- to long-span bridges. Despite their many advantages, various concerns have been raised regarding their maintenance due to the potential of fatigue crack initiation at welded details, accelerated corrosion in thin webs, and trapped debris around stiffeners. The use of rolled beams, on the other hand, can be very beneficial because they require much less maintenance. However, they are limited in size, which imposes constraints on their use to relatively short-span bridges due to deflection requirements. In this study, the behavior of the double composite superstructure system was …

Assessing The Predictive Capability Of The Nno Ballistic Limit Equation For Low-Density Projectile Impact, William P. Schonberg

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The design of nearly all Earth-orbiting spacecraft includes some sort of added shielding that protects the spacecraft against impacts by meteoroids and orbital debris. The effectiveness of the shielding is typically assessed using ballistic limit equations (BLEs) that are developed using data from high-speed impact tests on key spacecraft components and elements. These equations predict whether or not a particular system or structural element will sustain a critical failure following a specific impact event. As such, they are essential components of spacecraft system design as well as any quantitative spacecraft risk assessments that may need to be performed as part …