Civil and Environmental Engineering Commons^™

Comparison Of Prestress Losses For Pedestrian Bridges Constructed With High-Strength Concrete And High-Strength Self-Consolidating Concrete, John J. Myers, Kurt E. Bloch

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Abstract Two precast prestressed high-strength concrete and high-strength self-consolidating concrete pedestrian bridges were designed and erected in Rolla, Missouri, for an in situ investigative study to monitor time-dependent losses. Using the temperature and strain data monitored by the vibrating wire strain gauges within the beam cross sections, time-dependent losses were determined and compared between the bridges and various empirical expressions presented by AASHTO and the Precast/Prestressed Concrete Institute. © 2013 American Society of Civil Engineers.

The Effect Zeolite Addition In Natural Rubber Polypropylene Composite On Mechanical, Structure, And Thermal Characteristics, Nurdin Bukit, Erna Frida

Makara Journal of Technology

This study was conducted to determine the effect of zeolite as filler on mechanical properties, and thermal structure blends of natural rubber and polypropylene (NR/PP). In this study, NR/PP/PP-g-MA blends was filled uncalcined zeolite and calcined zeolite at different weight percent of the 2, 4, and 6%. Samples were characterized to determine the tensile strength, fracture elongation and Young's modulus. Structure of the samples was investigated using XRD method and thermal characteristics were analyzed using DTA/TGA technique. The results obtained for tensile strength showed a significant influence with the addition zeolite of the NR/PP blends at 2% by weight of …

Characteristics Of Vacuum Freeze Drying With Utilization Of Internal Cooling And Condenser Waste Heat For Sublimation, Muhammad Idrus Alhamid, Nasruddin Yusuf, Indra Teuku Meurah Mahlia, Engkos Ahmad Kosasih, Muhamad Yulianto, Rio Ricardi

Makara Journal of Technology

Vacuum freeze drying is an excellent drying method, but it is very energy-intensive because a relatively long drying time is required. This research investigates the utilization of condenser waste heat for sublimation as a way of accelerating the drying rate. In addition, it also investigates the effect of internal cooling combined with vacuum cooling in the pressure reduction process. Jelly fish tentacles were used as the specimen, with different configurations for condenser heat waste and internal cooling valve opening. The results show that heating with condenser heat waste can accelerate the drying rate up to 0.0035 kg/m2.s. In addition, pre-freezing …

A New Experimental Approach To Evaluate Plasma-Induced Damage In Microcantilever, Yuki Nishimori, Shinji Ueki, Masakazu Sugiyama, Seiji Samukawa, Gen Hashiguchi

Makara Journal of Technology

Plasma etching, during micro-fabrication processing is indispensable for fabricating MEMS structures. During the plasma processes, two major matters, charged ions and vacuum–ultraviolet (VUV) irradiation damage, take charge of reliability degradation. The charged ions induce unwanted sidewall etching, generally called as “notching”, which causes degradation in brittle strength. Furthermore, the VUV irradiation gives rise to crystal defects on the etching surface. To overcome the problem, neutral beam etching (NBE), which use neutral particles without the VUV irradiation, has been developed. In order to evaluate the effect of the NBE quantitatively, we measured the resonance property of a micro-cantilever before and after …

Fatigue Life Prediction Of The Keel Structure Of A Tsunami Buoy Using Spectral Fatigue Analysis Method, Angga Yustiawan, Ketut Suastika, Wibowo Harso Nugroho

Makara Journal of Technology

One of the components of the Indonesia Tsunami Early Warning System (InaTEWS) is a surface buoy. The surface buoy is exposed to dynamic and random loadings while operating at sea, particularly due to waves. Because of the cyclic nature of the wave load, this may result in a fatigue damage of the keel structure, which connects the mooring line with the buoy hull. The operating location of the buoy is off the Java South Coast at the coordinate (10.3998 S, 108.3417 E). To determine the stress transfer function, model tests were performed, measuring the buoy motions and the stress at …

The Plasma Electrolysis Phenomenon In A Two-Compartment Reactor For Chlor-Alkali Production, Nelson Saksono, Fakhrian Abqari, Setijo Bismo

Makara Journal of Technology

Chlor-alkali is one of the most important processes in the chemical industry. It produces chlorine and caustic soda, which become the main feedstock of daily products. The aim of this study is to report the phenomenon of plasma electrolysis and how it can be used in chlor-alkali production for more efficient energy consumption. When the plasma is formed, the current fluctuates and gradually declines. Plasma electrolysis begins with the process of electrolysis itself. Due to Joule heating, gas bubbles are formed and a sheath is made on both electrodes, resulting in the plasma field. Plasma electrolysis can be identified by …

Observation Of Photovoltaic Effect And Single-Photon Detection In Nanowire Silicon Pn-Junction, Arief Udhiarto, Sri Purwiyanti, Daniel Moraru, Takeshi Mizuno, Michiharu Tabe

Makara Journal of Technology

We study nanowire silicon pin and pn-junctions at room and low temperature. Photovoltaic effects are observed for both devices at room temperature. At low temperature, nanowire pn-junction devices show their ability to detect single photon. This ability was not been observed for pin devices. Phosphorus-boron dopant cluster in the depletion region is considered to have the main role for single-photon detection capability. Fundamental mechanism of dopant-based single-photon detection in nanowire pn-junction is described in details.

Influences Of Surface Morphology Of Nanostructured Rutile Tio2 Nanorods/Nanoflowers As Photoelectrode On The Performance Of Dye-Sensitized Solar Cell, Mohd Khairul Bin Ahmad, Kenji Murakami

Makara Journal of Technology

Aligned Rutile TiO2 nanorods (r-TNRs) and TiO2 nanoflowers (r-TNFs) were successfully prepared by hydrothermal method. Using hydrochloric acid (HCl) as chelating agent and titanium butoxide (TBOT) as precursor, aligned r-TNRs with r-TNFs were successfully growth onto fluorine-doped tin oxide (FTO) with different morphologies. The influences of surface morphologies to the rutile based Dye-sensitized solar cell (DSC) efficiency are discussed. The highest lightto- electric energy conversion efficiency, 1.80% is achieved using different concentration under simulated solar light illumination of 100 mWcm-2 (1.5 AM).

Improvement In Performance Of Zno Based Dsc Prepared By Spraying Method, Rangga Winantyo, Devinda Liyanage, Kenji Murakami

Makara Journal of Technology

This paper reports the effect of TiCl4 on the performance of ZnO based DSC. ZnO was used due to its stability against photo-corrosion and photochemical properties similar to TiO2. Thin films of nanocrystalline ZnO were deposited on transparent conducting oxide glass using spray method. The ZnO films were treated using TiCl4. The cell’s efficiency was found to be 2.5% with TiCl4 post-treatment and 1.9% without TiCl4 post-treatment.

Determining The Air Gap Length Of An Axial Flux Wound Rotor Synchronous Generator, Abdul Multi, Iwa Garniwa, Uno Bintang Sudibyo

Makara Journal of Technology

The air gap length of the designed axial flux wound rotor (AFWR) synchronous generator is determined properly according to the design parameters. One of the distinct advantages of an axial flux (AF) machine is its adjustable air gap. An AF generator’s performance might be controlled by adjusting its air gap. The designed generator has a smallscale capacity that has 1 kW, 380 V, and 50 Hz. The windings are laid into slots made from laminated core. The slots are carved in the face of the stator and rotors. The generator has a single-double-sided slotted wound stator sandwiched between twin rotors. …

Production Optimization For Plan Of Gas Field Development Using Marginal Cost Analysis, Suprapto Soemardan, Widodo Wahyu Purwanto, Arsegianto Arsegianto

Makara Journal of Technology

Gas production rate is one of the most important variables affecting the feasibility plan of gas field development. It take into account reservoir characteristics, gas reserves, number of wells, production facilities, government take and market conditions. In this research, a mathematical model of gas production optimization has been developed using marginal cost analysis in determining the optimum gas production rate for economic profit, by employing the case study of Matindok Field. The results show that the optimum gas production rate is mainly affected by gas price duration and time of gas delivery. When the price of gas increases, the optimum …

Reliability Analysis Of Shallow Foundations Bearing Capacity On Sand, Ali Alhajami

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

Bearing capacity of shallow foundation is one of the most challenging problems for engineers. The difficulty comes from multiple sources of variability and uncertainty. There is an uncertainty in live load. Soil properties including: unit weight, cohesion, and angle of friction represent sources of variability in the determining bearing capacity. The current theories used in practice only estimate bearing capacity and does not give an exact value for it because of these sources of variability. Currently, there are Terzaghi, Meyerhof, Vesic, and Hansen theories for dealing with this problem. Based on previous research Terzaghi theory was found to be the …

Energy Dissipation Of Thin-Walled Cold-Formed Steel Members, David A. Padilla-Llano, Christopher D. Moen, Matthew Eatherton

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

No abstract provided.

Weighing The Financial And Sustainable Benefits Of High Performance Structures In Seismically Active Regions, Alia Talina Barajas

Master's Theses

This thesis investigated the potential advantages and disadvantages of high performance structures by comparing the financial and environmental impacts of a performance based four-story office building to one designed to meet minimum code-level requirements.

To generate a comparison, the lateral system of a four-story structure utilizing buckling restrained braced frames was designed to meet code-level requirements per the American Society of Civil Engineers’ Minimum Design Loads for Buildings and Other Structures (ASCE 7-05) and again to meet the immediate occupancy criteria defined by ASCE 41-06 Seismic Rehabilitation of Existing Buildings. The following was then performed:

• Test the structural performance of …

Reliability-Based Topology Optimization Of Trusses With Stochastic Stiffness, Mehdi Jalalpour, James K. Guest, Takeru Igusa

Civil and Environmental Engineering Faculty Publications

A new method is proposed for reliability-based topology optimization of truss structures with random geometric imperfections and material variability. Such imperfections and variability, which may result from manufacturing processes, are assumed to be small in relation to the truss dimensions and mean material properties and normally distributed. Extensive numerical evidence suggests that the trusses, when optimized in terms of a displacement-based demand metric, are characterized by randomness in the stiffness that follow the Gumbel distribution. Based on this observation, it was possible to derive analytical expressions for the structural reliability, enabling the formulation of a computationally efficient single-loop reliability-based topology …

The Effect Of Microencapsulated Phase-Change Material On The Compressive Strength Of Structural Concrete, Chad Norvell, David J. Sailor, Peter Dusicka

Mechanical and Materials Engineering Faculty Publications and Presentations

Latent heat energy storage through phase-change materials (PCMs) is one possible strategy to control interior temperatures in buildings, improve thermal comfort, and passively reduce building energy use associated with heating and cooling. While PCMs integrated into building structure elements have been studied since the 1970s, challenges of integrating PCMs into building materials while maintaining their heat storage benefits have limited their application in practice. The recent introduction of microencapsulated phase-change materials provides the energy storage capability of PCMs in micron-scale, chemically-inert capsules that can be easily integrated into composite materials such as gypsum wallboard and concrete. The size and physical …

Structural Reliability Analysis Of Corroded Steel Girder Bridge, Mohammed Shaalan Al Badran

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

The natural aging, environmental impact, and appropriate design are certainly playing a serious role in safety of the bridges function. The functional safety of bridge constitutes a prime element of the transportation system serving commuters, passengers and freight. According to Federal Highway Administration, the steel bridges share represents a large amount of the United States’ bridges. In last century, the collapse of both the Silver Bridge at Point Pleasant, West Virginia over the Ohio River on December 15, 1967 and over the Mianus River Bridge in Connecticut on June 28, 1983 showed that steel corrosion has been the leading reason …

Public Works Projects As Vehicles For Engineering Education And Outreach, Shannon Weiss, David Heil, Thalia Anagnos

Faculty Publications

America is built on small and large feats of public works engineering that, although often taken for granted, affect almost every aspect of our daily lives. So how can we celebrate these marvels of utilitarian infrastructure and use them to teach public audiences about the engineering principles, materials, and human innovations that make them possible? This case study will share how one project addressed these questions by leveraging informal learning strategies, multi-agency collaborations, and new media technologies to explain the history and engineering of one of the world’s most recognizable public work sites: the Golden Gate Bridge. This paper will …

Reliability-Based Design Optimization Of Concrete Flexural Members Reinforced With Ductile Frp Bars, Bashar Behnam, Christopher D. Eamon

Civil and Environmental Engineering Faculty Research Publications

In recent years, ductile hybrid FRP (DHFRP) bars have been developed for use as tensile reinforcement. However, initial material costs regain high, and it is difficult to simultaneously meet strength, stiffness, ductility, and reliability demands. In this study, a reliability-based design optimization (RBDO) is conducted to determine minimum cost DHFRP bar configurations while enforcing essential constraints. Applications for bridge decks and building beams are considered, with 2, 3, and 4-material bars. It was found that optimal bar configuration has little variation for the different applications, and that overall optimized bar cost decreased as the number of bar materials increased.

North American Specification For The Design Of Cold-Formed Steel Structural Members, 2012 Edition, American Iron And Steel Institute

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

No abstract provided.

The Effect Of Truck Permitting Policy On Us Bridge Loading, Eugene J. Obrien, Bernard Enright, Cathal Leahy

Conference papers

No abstract provided.

Another Look At The Collapse Of Skyline Plaza At Bailey’S Crossroads, Virginia, Jeffrey Schellhammer, Norbert Delatte, Paul A. Bosela

Civil and Environmental Engineering Faculty Publications

On March 2, 1973, the Skyline Plaza apartment building in Bailey’s Crossroads, Virginia collapsed while under construction. The Occupational Health and Safety Administration (OSHA) requested an investigation from the National Bureau of Standards [(NBS); now the National Institute of Standards and Technology (NIST)]. The NBS team concluded that the most likely cause of the collapse was a punching shear failure of the 23rd floor slab. The two factors that contributed to this were premature removal of shores below the 23rd floor slab, and the low strength of the 23rd floor concrete in the area supporting the weight of the 24th …

Seismic Performance Comparison Of A Fixed-Base Versus A Base-Isolated Office Building, Nicholas Reidar Marrs

Master's Theses

The topic of this thesis is base isolation. The purpose of this thesis is to offer a relative understanding of the seismic performance enhancements that a typical 12-story steel office building can achieve through the implementation of base isolation technology. To reach this understanding, the structures of a fixed-base office building and a base-isolated office building of similar size and layout are designed, their seismic performance is compared, and a cost-benefit analysis is completed. The base isolation system that is utilized is composed of Triple Friction Pendulum (TFP) bearings.

The work of this thesis is divided into four phases. First, …

Seismic Rehabilitation Of Steel Moment Frames Vulnerable To Soft-Story Failures Through Implementation Of Rocking Cores, Juan Carlos Sanchez

Master's Theses

During seismic events, inefficient steel moment frame building systems may exhibit soft-story failures. This thesis focuses on development and validation of a seismic retrofit strategy for avoiding soft-story failures in low-rise and mid-rise steel moment frame buildings. The considered retrofit strategy consists of a sufficiently stiff Rocking Core (RC) pinned to the foundation and pin connected to the existing frame. For demonstration purposes, two representative benchmark steel moment frames, which are modified from the three- and nine-story pre-Northridge steel moment frames designed for Los Angeles in the SAC Steel Project, are considered. Finite Element (FE) models of the benchmark buildings …

Reliability-Based Bridge Assessment Using Enhanced Monte Carlo To Simulate Extreme Traffic Loading, Bernard Enright, Donya Hajializadeh, Eugene J. Obrien

Conference papers

A framework is presented for the assessment of the safety of a bridge deck under actual traffic loading using an enhanced Monte Carlo method which attempts to reduce computational cost while preserving the advantages of more conventional, computationally intensive, simulation. To generate the bridge loading scenarios, an extensive Weigh-in-Motion (WIM) database is used to calibrate a sophisticated simulation model of two-directional traffic. Traffic and vehicle characteristics are generated from statistical distributions derived from measured traffic data. Two examples are used in this study to assess the usefulness and accuracy of the enhanced method. In the first, a simple example is …

Exploring Factors Contributing To Injury Severity At Freeway Merging And Diverging Locations In Ohio, Worku Y. Mergia, Deogratias Eustace, Deo Chimba, Maher Butros Qumsiyeh

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Identifying factors that affect crash injury severity and understanding how these factors affect injury severity is critical in planning and implementing highway safety improvement programs. Factors such as driver-related, traffic-related, environment-related and geometric design-related were considered when developing statistical models to predict the effects of these factors on the severity of injuries sustained from motor vehicle crashes at merging and diverging locations. Police-reported crash data at selected freeway merging and diverging areas in the state of Ohio were used for the development of the models. A generalized ordinal logit model also known as partial proportional odds model was applied to …

Seismic Rehabilitation Of Steel Concentrically Braced Frames Vulnerable To Soft-Story Failure Through Implementation Of Rocking Cores, Francisco Sanchez-Zamora

Master's Theses

Recent research reports that steel Concentrically Braced Frames (CBFs) (even the code-compliant ones) may be susceptible to soft-story failures during strong earthquakes. Such a failure mode causes catastrophic outcomes and should be definitely avoided in practice. This thesis focuses on development and validation of a seismic retrofit strategy for low-rise and mid-rise steel CBFs vulnerable to soft-story failures. The considered retrofit strategy consists of a sufficiently stiff rocking core (RC) pinned to foundation and connected to the existing frame. For demonstration purpose, two representative benchmark steel CBF buildings, which are the three-and six-story CBFs designed forLos Angelesin the SAC Steel …

Seismic Design Manual For Interlocking Compressed Earth Blocks, Nicholas Edwards Kennedy

Master's Theses

Seismic Design Manual for Interlocking Compressed Earth Blocks

Nicholas Edwards Kennedy

This thesis presents a comprehensive seismic design manual to be used to design and construct simple Interlocking Compressed Earth Block (ICEB) structures in seismically active regions. ICEBs are earth blocks made primarily of soil and stabilized with cement. They have female and male stud mechanisms designed to interlock when stacked, eliminating the need for mortar. The blocks can accept reinforcement and grout after they are placed. While ICEB construction is similar to conventional masonry construction, current design code standards for masonry only partially capture the actual behavior of ICEB …

Fatigue Testing And Data Analysis Of Welded Steel Cruciform Joints, Alina Shrestha

LSU New Orleans Theses and Dissertations

In this study, ABS Publication 115, “Guidance on Fatigue Assessment of Offshore Structures” is briefly reviewed. Emphasis is on the S-N curves based fatigue assessment approach of non-tubular joints, and both size and environment effects are also considered. Further, fatigue tests are performed to study the fatigue strength of load-carrying and non-load-carrying steel cruciform joints that represent typical joint types in marine structures. The experimental results are then compared against ABS fatigue assessment methods, based on nominal stress approach, which demonstrates a need for better fatigue evaluation parameter. A good fatigue parameter by definition should be consistent and should correlate …

Creep, Fatigue And Creep-Fatigue Interactions In Modified 9% Cr - 1% Mo (P91) Steels, Valliappa Kalyanasundaram

Graduate Theses and Dissertations

Grade P91 steel, from the class of advanced high-chrome ferritic steels, is one of the preferred materials for many elevated temperature structural components. Creep-fatigue (C-F) interactions, along with oxidation, can accelerate the kinetics of damage accumulation and consequently reduce such components' life. Hence, reliable C-F test data is required for meticulous consideration of C-F interactions and oxidation, which in turn is vital for sound design practices. It is also imperative to develop analytical constitutive models that can simulate and predict material response under various long-term in-service conditions using experimental data from short-term laboratory experiments. Consequently, the major objectives of the …