Structural Engineering Commons^™

Underwater Explosion Energy Dissipation Near Waterborne Infrastructure, Paul R. Smith

Theses and Dissertations--Civil Engineering

Underwater explosions pose a significant threat to waterborne infrastructure though destructive pressure waves that can travel significant distances through the water. However, the use of bubble screens can attenuate the peak pressure and energy flux created by explosions to safe levels. This study investigates the prediction of pressure wave characteristics based on accumulated data, the damage potential of underwater explosions based on applied loads and effective material strength, and the bubble screen parameters required to prevent damage. The results were compiled to form a procedure for the design and implementation of a bubble screen the protection of waterborne infrastructure.

Preliminary Investigation Into The Rate Of Carbonation Of Concrete Blocks Under Normal Production Yard Conditions, Aimee Byrne, Eanna Nolan

Conference papers

The release of CO2 from calcination during the manufacture of cement can be partially or fully offset by the CO2 it naturally absorbs during its lifetime. This paper reports results from a preliminary investigation into the rate of carbonation in concrete blocks stacked in a production yard over a period of 6 months. The blocks were stacked in a normal manner under natural exposure conditions. Carbonation progress was determined by splitting the blocks and spraying the freshly exposed surface with a phenolphthalein solution at intervals over the test period. It was found that the rate of the carbonation front progression …

Thermal Envelope Analysis Of Local Authority Low Rise Housing Based On Stock Aggregation Theory Using A Remote Feature Extraction Technique., James Pittam

Theses

Understanding the buildings thermal envelope is paramount to analysing existing problems which facilitate cold bridging and low surface temperatures. As no detailed housing stock database is in existence in Ireland which describes the geometrical configuration of the existing housing stock, and to create one would be a major challenge, this research set out to develop a high speed remote cataloguing and geometrical data extraction methodology to build such a database. Replacing traditional measurement methods with a remote method allows for the rapid extraction of fagade information. A remote surveying process is proposed named, the Virtual Survey Method, for the classification …

Precast Full-Depth Deck Panels Supported On Inverted Bulb-Tee Bridge Girders, Michael James Mingo

Electronic Theses and Dissertations

The South Dakota Department of Transportation (SDDOT) currently uses precast double-tee bridge deck systems for many of its county bridges because they are economical and fast in construction. Current bridges are designed for a service life of 75 years. However, many double-tee girder bridges are deteriorating and some need total replacement after 40 years in service. Furthermore, the double-tee bridge system only has one supplier in South Dakota. Alternative durable precast or prefabricated bridge systems are needed to provide more options to local governments when designing a new bridge. Different alternatives will also give local governments more flexibility to select …

Using Photovoltaics To Power Electrochemical Chloride Extraction From Concrete, Sean Bond, Lynette O'Callaghan, Niall Holmes Dr., Brian Norton

Conference papers

Corrosion of embedded steel in reinforced concrete (RC) is a world-wide problem, that reduces structural performance and lifespan. Chloride attack may be a result of seawater, de-icing salts or contaminated admixtures, brought on by ingress of chlorides into the concrete. Electrochemical Chloride Extraction (ECE) is a non-destructive treatment for contaminated RC structures, that due to uncertainty of treatment times and applied current densities, is only 50% effective. It is often diesel powered has an environmental impact and often very costly due to the long treatment times. To improve the efficiency of ECE the influences of concrete resistance, cement type and …

Structural Health Monitoring Of Composite Overwrapped Pressure Vessels, Luca Letizia

Honors Undergraduate Theses

This work is focusing to study the structural behavior of Composite Overwrapped Pressure Vessels (COPVs). These COPVs are found in many engineering applications. In the aerospace field, they are installed onto spaceships and aid the reorientation of the spacecraft in very far and airless, therefore frictionless, orbits to save energy and fuel. The intent of this research is to analyze the difference in performance of both perfectly intact and purposely damaged tanks. Understanding both the source and location of a structural fault will help NASA engineers predict the performance of COPVs subject to similar conditions, which could prevent failures of …

Sinkhole Monitoring Using Groundwater Table Data, Ton Tu

Electronic Theses and Dissertations

Florida might be one of the most sinkhole-active areas on the earth. Due to its unpredictability and significance of occurrence, the development of sinkhole monitoring techniques is imperative to minimize sinkhole-induced hazards. Several methods have been used to evaluate sinkhole risks, including destructive methods, such as Standard Penetrating Tests (SPT) and Cone Penetrating Tests (CPT), geophysical method, and sensor-based groundwater monitoring method. However, few studies are available for comprehensive understanding of spatiotemporal sinkhole mechanism by combining different exploration methods under realistic experimental conditions. The objective of this study is to understand spatiotemporal sinkhole mechanism, using SPT, CPT, ground penetrating radar …

Heterogeneous Thermal Effects On Structural-Grade Steel, Eric Wickersham

Williams Honors College, Honors Research Projects

The AISC Steel Construction Manual covers structural steel design while at atmospheric and elevated temperatures. The manual does not, though, cover what happens to the steel after it has cooled from elevated temperatures. To fill in this knowledge gap, A36 steel was studied with respect to three main criteria: time, temperature, and cooling. Time was sub-divided into a standard burn (17-20min) and a prolonged burn (90min). Temperature was sub-divided into an average burn (600-800⁰F) and an extreme burn (>1200⁰F). To reach such temperatures, a forge was constructed and used during the burning process. Cooling was sub-divided into standard (air …

An Exploration Of Structural Timber Innovation, Simon Beskitt

Williams Honors College, Honors Research Projects

In many undergraduate programs of study, civil and structural engineering students are exposed to introductory material regarding timber construction. The information received in the undergraduate experience typically consists of a brief summary of the basic mechanical properties of wood but does not significantly cover timber design. Much greater emphasis is placed on design practices involving steel and concrete, likely due to their prominence in contemporary building trends in civil engineering. While it is true that wood is one of the older materials in terms of its utilization in structural and architectural design, it is certainly not an antiquated choice. Wood …

Corrosion Protection Systems In Offshore Structures, Hristo Ivanov

Williams Honors College, Honors Research Projects

Corrosion plays a pivotal role in the engineering world. Engineers of all disciplines must consider the dangers that this phenomenon can incur. Interestingly, corrosion mitigation is not a topic that is addressed in most academic curricula. The goal of this paper is to give engineering students a brief introduction into corrosion and some of the prevention techniques commonly used today.

The design of a corrosion protection system for offshore structures is discussed in order to illustrate how these techniques can be utilized even in the most extreme environments. First, the driving force behind corrosion is examined, introducing the basic mechanics …

Effect Of Fiber Orientation On Dynamic Compressive Properties Of An Ultra-High Performance Concrete, Andrew B. Groeneveld

Dissertations, Master's Theses and Master's Reports

Casting structural elements with ultra-high performance concrete (UHPC) tends to create preferential fiber alignment, which affects the strength and must be accounted for in design. Fiber orientation effects in tension have been studied extensively, but less work has been performed for compression. This work characterizes the fiber orientation occurring in a typical UHPC beam and how that orientation affects compressive behavior at high strain rates. Specimens (36 total) were cored from the beam and their fiber orientations were non-destructively evaluated using x-ray computed tomography (CT). Fibers showed flow-induced alignment along the length of the beam, with orientation angles in the …

Probability-Based Hurricane Resilience Evaluation And Retrofitting For Residential Community, Yadong Dong

Dissertations, Master's Theses and Master's Reports

Wood residential construction is vulnerable to hurricanes, as evident in recent hurricane events. Many studies indicated that the changing climate may very likely alter hurricane patterns, which could lead to more severe hurricane damage to the wood residential construction that accounts for 90% of the residence in the USA. On the other hand, deterioration of material increases the chance of structural failure by reducing the structural capacity (e.g., corrosion of fasteners in roof panel could significantly reduce the withdrawal capacity of the roofing structure during hurricane events).

Currently, most hurricane damage estimations only focus on direct loss (e.g., structural loss). …

Structural Control Of Wind Turbines With Soil Structure Interaction Included, Breiffni Fitzgerald, Biswajit Basu

Articles

The importance of considering soil structure interaction in structural control of wind turbines is investigated in this paper. An Euler–Lagrangian wind turbine mathematical model based on an energy formulation was developed for this purpose which considers the structural dynamics of the system and the interaction between in-plane and out-of-plane blade vibrations. Also, the interaction between the blades and the tower including a tuned mass damper (TMD) is considered. The turbine is subject to turbulent aerodynamic loading simulated using a modification to the classic Blade Element Momentum (BEM) theory with turbulence generated from rotationally sampled spectra. The turbine is also subject …

Risk-Based Assessment And Strengthening Of Electric Power Systems Subjected To Natural Hazards, Abdullahi Salman

Dissertations, Master's Theses and Master's Reports

Modern economic and social activities are dependent on a complex network of infrastructure systems that are highly interdependent. Electric power systems form the backbone of such complex network as most civil infrastructure systems cannot function properly without reliable power supply. Electric power systems are vulnerable to extensive damage due to natural hazards, as evident in recent hazard events. Hurricanes, earthquakes, floods, tornados and other natural hazards have caused billions of dollars in direct losses due to damage to power systems and indirect losses due to power outages, as well as social disruption. There is, therefore, a need for a comprehensive …

An Overview Of The Development Of Cement-Based Batteries For The Cathodic Protection Of Embedded Steel In Concrete, Aimee Byrne, Niall Holmes, Brian Norton

Conference papers

This paper presents an overview of the cement-based batteries developed in DIT for use in the cathodic protection of embedded steel in reinforced concrete undergoing chloride-induced corrosion. Cathodic protection delivers an external current (approximately 20mA per m2 of embedded steel) which effectively polarises the internal current generated during corrosion. The batteries developed in DIT comprise of a cement-based electrolyte containing different additives including sand, aggregate, salts, carbon black and plasticiser with protruding anode and cathode metal plates. These batteries produced an initial electrical output of 1.5V and 23mA through a 10 resistor as measured using data acquisition units and a …

Influence Of The Substrate Characteristics On The Bond Behavior Of Pbo Frcm-Concrete Joints, Tommaso D'Antino, Lesley H. Sneed, Christian Carloni, Carlo Pellegrino

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Fiber Reinforced Cementitious Matrix (FRCM) composites can be employed as a valid alternative to Fiber Reinforced Polymers (FRP) composites for strengthening existing reinforced concrete (RC) structures. The weakness of FRCM-concrete joints has been reported to be at the matrix-fiber interface rather than within the concrete substrate, as is usually reported in the case of FRP-concrete joints. The experimental investigations regarding FRCM strengthening available in the literature have been performed by applying the FRCM composite onto a surface that was treated before the application, usually by grinding or sandblasting. However, the role of the substrate characteristics on the failure mechanism of …

An Assessment Of The Accuracy Of The Euler-Bernoulli Beam Theory For Calculating Strain And Deflection In Composite Sandwich Beams, Qhinhon D. Ho

LSU New Orleans Theses and Dissertations

This study focuses on assessing the accuracy of the Euler-Bernoulli beam theory as computational bases to calculate strain and deflection of composite sandwich beam subjected to three-point and four-point bending. Two groups of composite sandwich beams tests results will be used for comparison purposes. Mechanical properties for the laminated skin are provided by researchers from University of Mississippi (Ellen Lackey et al., 2000). Mechanical properties for the balsa wood core are provided by Alcan Baltek Corporation. Appropriate material properties and test geometries are then used in the Euler-Bernoulli-based algorithm in order to generate analytical data for comparison to experimental data …

Improving Renewable Energy Transition Acceptance: A Simulation Gaming Approach On A Multi Actor Setting In The Netherlands, Aziiz Sutrisno, Jac A. M. Vennix, Noor Syaifudin

Makara Journal of Technology

The Netherlands have tried very hard to increase their renewable energy sources (RES) shares to fulfill the European Union target in 2050. However, RES performance did not show the expected result as the performance declined in 2009 producing even wider gap compare to the target. The Dutch government’s tried to incorporate all interested stakeholders by forming the Dutch energy transition task force. Nevertheless, the task force’s result is also not showing a desirable trend. Key reasons behind the Dutch low RES performance are the lack of shared understanding and positive attitude toward RES development among interested actors. This research uses …

Dual-Band Singly-Fed Proximity-Coupled Tip-Truncated Triangular Patch Array For Land Vehicle Mobile System, Basari Basari, Josaphat Tetuko Sri Sumantyo

Makara Journal of Technology

This paper proposes a dual-band left-handed circularly polarized triangular-patch array that is developed for land vehicle mobile system aimed at mobile satellite communications. The array consists of six tip-truncated triangular patches, which the first three patches are used for reception and the second three patches are used for transmission purpose. Each of three-patches has a beam pattern that can be switched in three different 120°-coverage beam in azimuth-cut plane at a minimum targeted gain at a desired elevation angle. The targeted minimum gain of the array is 5 dBic, in order for data communications with a large geostationary satellite can …

Improvement Of Quality Of Carica Papaya L. With Clove Oil As Preservative In Edible Coating Technology, Eny Kusrini, Anwar Usman, Chrispine Deksita Wisakanti, Rita Arbianti, Dedy Alharis Nasution

Makara Journal of Technology

We have studied utilization of essential clove oil, extracted from clove buds by hydrodistillation, as preservative in edible packaging technology. Preservative of essential clove oil was applied on chopped papaya fruits by using two methods, namely spray and brush. The effects of concentration of clove oil from 0.05 to 0.20% on the preservation of papaya fruits (Carica papaya L.) at room temperature (25 °C) were also evaluated. Physicochemical and in vitro microbiological activities on the papaya fruits that were stored at 25 oC and 85-90% relative humidity were investigated in details. The results indicate that the clove oil at concentration …

Calibration Of Numerical Model For Shoreline Change Prediction Using Satellite Imagery Data, Sigit Sutikno, Keisuke Murakami, Dwi Puspo Handoyo, Manyuk Fauzi

Makara Journal of Technology

This paper presents a method for calibration of numerical model for shoreline change prediction using satellite imagery data in muddy beach. Tanjung Motong beach, a muddy beach that is suffered high abrasion in Rangsang Island, Riau province, Indonesia was picked as study area. The primary numerical modeling tool used in this research was GENESIS (GENEralized Model for Simulating Shoreline change), which has been successfully applied in many case studies of shoreline change phenomena on a sandy beach.The model was calibrated using two extracted coastlines satellite imagery data, such as Landsat-5 TM and Landsat-8 OLI/TIRS. The extracted coastline data were analyzed …

Independency Of Elasticity On Residual Stress Of Room Temperature Rolled Stainless Steel 304 Plates For Structure Materials, Parikin Parikin, David Allen

Makara Journal of Technology

Mechanical strengths of materials are widely expected in general constructions of any building. These properties depend on its formation (cold/hot forming) during fabrication. This research was carried out on cold-rolled stainless steel (SS) 304 plates, which were deformed to 0, 34, 84, and 152% reduction in thickness. The tests were conducted using Vickers method. Ultra micro indentation system (UMIS) 2000 was used to determine the mechanical properties of the material, i.e.: hardness, modulus elasticity, and residual stresses. The microstructures showed lengthening outcropping due to stress corrosion cracking for all specimens. It was found that the tensile residual stress in a …

Oxidation Process Of H 2 O /Uv For Cod Reduction Of Wastewater From Soybean Tofu Production, Komala Pontas, Abrar Muslim

Makara Journal of Technology

Chemical Oxygen Demand (COD) reduction of wastewater from soybean tofu production was studied by conducting advanced oxidation process (AOP) using hydrogen peroxide with UV radiation catalysts in a closed cylindrical glass reactor. The hydroxyl radical (*OH) concentration from H2O2 decomposition was modeled, and exponential trends were found for the *OH concentration over radiation time and operation temperature. As a result, it was found that the maximal *OH concentration was 0.209 mol L-1 at 240 minutes and 50 °C. The *OH concentration exponentially increased following rise in operation temperature. The H2O2/UV AOP application reduced COD concentration to approximately 42.41% from 10,545 …

Uplift Of Shoreline Regions On Pagai Island Due To The September 12, 2007 Mw 8.4 Earthquake Captured By Sar Image, Ashar Muda Lubis

Makara Journal of Technology

At least 25 people were killed by the September 12, 2007 Mw 8.4 Bengkulu earthquake, and many buildings were destroyed in Bengkulu and West Sumatra provinces. It is very important to estimate the earth surface deformation due to the earthquake to understand the rupture size and its process. The aim of this research is to estimate the shoreline change and vertical displacement on Pagai Island associated with the September 12, 2007 Mw 8.4 Bengkulu earthquake. The intensity of ALOS-PALSAR satellite images is used to access the pattern of displacement. The result shows that Pagai Island demonstrated huge uplift due to …

Effect Of Fly Ash Fortification In The Manufacture Process Of Making Concrete Towards Characteristics Of Concrete In Sulfuric Acid Solution, Asep Handaya Saputra, Muhammad Shohibi, Masatoshi Kubouchi

Makara Journal of Technology

Fly ash is a silica or alumino silica material that can be used as a constituent of cement in the concrete manufacturing process. Utilization of fly ash aims to improve durability and minimize the reduction of concrete’s compressive strength exposed to an acidic environment, which can be achieved through the pozzolanic reaction of fly ash with Ca(OH)2 within concrete. The reduced content of Ca(OH)2 through pozzolanic reaction will minimize the tendency of ettringite formation (compounds that cause deterioration and decrease the compressive strength of concrete). In order to determine the relation between fly ash replenishment into concrete with concrete’s characteristics …

North American Standard For Cold-Formed Steel Framing -- Nonstructural Members, 2015 Edition, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

North American Standard For Cold-Formed Steel Structural Framing, 2015 Edition, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

North American Standard For Seismic Design Of Cold-Formed Steel Structural Systems, 2015 Edition With Supplement 1, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

Comparative Analysis Of Buckling-Restrained Braced Frames In Eccentric Configuration (Brbf-Es) And Eccentrically Braced Frames (Ebfs), Peter T. Vayda

Civil Engineering Undergraduate Honors Theses

Continuing on the findings of “Using Buckling-Restrained Braced Frames in Eccentric Configuration,” by Dr. Gary S. Prinz, P.E., which determined that, from a performance standpoint, BRBF-Es could be a viable alternative for EBFs. A comparative analysis was conducted on the design procedures and initial cost estimates of BRBF-Es and EBFs. Upon designing four 12-Story buildings (two BRBF-Es and two EBFs), it was determined that BRBF-Es were easier to design due to the statically determinant system. The initial costs estimates of BRBF-Es; however, ranged upwards of 30% more cost than EBFs. Therefore, the initial investment of more intensive structural engineering design …

Phase I Evaluation Of Selected Concrete Material Models In Ls-Dyna, Bradley J. Winkelbauer

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

Numerous roadside safety systems are configured with reinforced concrete materials, such as bridge railings, median barriers, and roadside parapets. These protective barrier systems are intended to safely contain and redirect errant vehicles as well as prevent impacts into hazardous fixed objects or other geometric features. The analysis and design of these structures may involve impact simulation with finite element software, like LS-DYNA, which includes multiple concrete material models. For such investigations, limited guidance is available for selecting preferred concrete material models and determining appropriate values for specific parameters. This Phase I study investigated the viability and performance of existing concrete …