Structural Engineering Commons^™

Compression Testing And Failure Modes Of Steel-Concrete Composite (Sc) Structures For Nuclear Containment, Patrick Michael Wanamaker, Amit H. Varma

The Summer Undergraduate Research Fellowship (SURF) Symposium

Although being able to provide much cleaner power than burning coal and other fossil fuels, nuclear power plants are still a tough sell to the general public due to their history of being spontaneously dangerous. The containment structures surrounding these nuclear plants, however, can play a huge role in reducing the risks associated with them. Relatively new designs for these containment assemblies, known as SC (steel-concrete composite) structures, aim to increase the strength and durability of the containment facilities while keeping costs down. By varying the spacing between shear studs, the ratio of concrete to steel, and the ratio of …

Real-Time-Hybrid-Simulation Of Multi-Degree-Of-Freedom Systems With Multiple Time Steps, Lanxi Liu, Arun Prakash

The Summer Undergraduate Research Fellowship (SURF) Symposium

Computational simulation and physical experiments are both widely used in testing the response of a structure under earthquake loadings, but physical experiments can be expensive for large problems and numerical may result in the loss of important structural behavior caused by a large amount of assumptions. Real-time hybrid simulation (RTHS) is a combination of these two approaches, which uses both a numerical and physical substructures that interact in real time to simulate structural behavior. The numerical and physical substructures are connected using a transfer system that enforces compatibility between them. The physical substructure needs to be run at a very …

Recursive Multi-Time-Step Coupling Of Multiple Subdomains, Yukun An, Payton Lindsay, Xiaowo Wang, Arun Prakash

The Summer Undergraduate Research Fellowship (SURF) Symposium

The need for efficient computation methods for modeling of large-scale structures has become critically important over the past few years. Efficient means of analysis often involve coupling in space through domain decomposition and multi scale methods in time. The multi-time-step coupling method is a coupling method in time which allows for efficient analysis of large-scale problems for structural dynamics where a large structural model is decomposed into smaller subdomains that are solved independently and then coupled back together to obtain the global solution. For coupling of more than two subdomains that are solved at different timesteps, we employ recursive methods. …

Validation Of Earthquake Simulations And Their Effects On Tall Buildings Considering Spectral Shape And Duration, Ting Lin, Gregory Deierlein, Nenad Bijelic

Civil and Environmental Engineering Faculty Research and Publications

No abstract provided.

Report On Laboratory Testing Of Fastening Of Cfs Track To Concrete Base Materials With Pafs, With Revision, Ricardo Ramirez, Roger A. Laboube

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

The 2012 AISI S100 Section E5 includes design provisions for power-actuated fasteners (PAFs) for connection of cold-formed steel (CFS) to steel base materials. However, a need exists to develop an in-depth understanding when CFS wall tracks are attached to concrete base materials as part of interior and exterior wall framing applications. Current code requirements, as specified by ASCE 7 – 2010 Chapter 13 (Exception to Section 13.4.5), limit individual PAFs in nonstructural component connections as part of distributed systems, to a sustained tension service load of 90 lbs in concrete and 250 lbs in steel in Seismic Design Categories D, …

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 …