Structural Engineering Commons^™

Numerical Evaluation Of The Lateral Behavior Of Vertical And Battered Pile Group Foundations Using 3-D Finite Element Modeling, Ahmad Souri

LSU Doctoral Dissertations

The design of pile foundations to resist lateral loads is essential in offshore structures and bridge foundations. The lateral behavior of piles has been studied in the past by experimental investigations coupled with analytical and numerical methods. The problem is complex due to the nonlinearities from soil behavior, gap formation, and pile-soil-pile interaction in pile groups (or the group effect). In this work, the finite element (FE) modeling was used to study the lateral behavior of pile groups. The FE method is robust and allows incorporating the necessary aspects for studying the behavior of pile groups. The nonlinear material behavior …

What Lessons Can Be Learned From The Delivery Of The First Building On The Grangegorman Campus Using Building Information Management (Bim)?, Pat O'Sullivan, Avril Behan

Conference papers

There is an acceptance that BIM, via data management, can be integrated with FM to reduce costs during the Operations and Maintenance stage of a project. However, what has not been documented is the ‘on the ground’ reality which can be reviewed as a lessons learnt exercise to improve the implementation of BIM FM for future projects. This case study sets out to explore the realities of a client’s adoption of BIM based upon the actual experience of the Greenway Hub. Rather than relying on anecdotal evidence the research was based upon the real practices and experiences of the Dublin …

Time-Dependent Prestress Loss Behavior Of Girders In Missouri Bridge A7957 Compared With A U.S. Data Set Of High-Performance Concrete Bridge Girders, Hayder H. Alghazali, John J. Myers

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this study, six precast, prestressed concrete girders were constructed and instrumented to measure prestress losses of bridge A7957 in Missouri. The concrete mixture for the bridge was designed with varying mechanical and rheological properties. High-strength concrete, high-strength self-consolidating concrete, and normal-strength self-consolidating concrete were used to construct the bridge girders. Vibrating wire strain gauges with integrated thermistors were embedded through the girders' cross sections to measure strains and temperatures. The measured short- and long-term prestress losses were compared with those obtained using different empirical models, specified in the AASHTO LRFD Bridge Design Specifications and in the PCI Design Handbook: …

Seismic Performance Of Hollow-Core Composite Columns Under Cyclic Loading, Mohanad M. Abdulazeez, Mohamed Elgawady

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper experimentally investigates the seismic behavior of a large-scale, hollow-core, fiber-reinforced, polymerconcrete- steel HC-FCS column under cyclic loading. The typical precast HC-FCS member consists of a concrete wall sandwiched between an outer fiber-reinforced polymer (FRP) tube and an inner steel tube. The FRP tube provides continuous confinement for the concrete wall, along the height of the column. The column is inserted into the footing and temporarily supported; then, the footing is cast in place around the column. The seismic performance of the precast HC-FCS columns was assessed and compared with previous experimental work. The compared column had the same …

Lab-On-Sensor For Structural Behavior Monitoring: Theory And Applications, Genda Chen

INSPIRE Archived Webinars

There are over 600,000 bridges in the U.S. National Bridge Inventory (NBI). Nearly 50% of them rapidly approach their design life and deteriorate at an alarming rate, particularly under an increasing volume of overweight trucks. Visual inspection as the current practice in bridge management is labor intensive and subjective, resulting in inconsistent and less reliable element ratings. Lab-on-sensor technologies can provide supplemental mission-critical data to the visual inspection for both qualitative and quantitative evaluations of structural conditions, and thus critical decision-making of cost-effective strategies in bridge preservation.

In this presentation, the design and operation characteristics of highway bridges are first …

Cyclic Compression Behavior Of Concrete-Filled Hybrid Large Rupture Strain Frp Tube, Monika Nain, Mohanad M. Abdulazeez, Mohamed Elgawady

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper experimentally investigates the behavior of concrete-filled-fiber-reinforced polymer (FRP) cylinders under cyclic axial compression. The FRP used in this study were either large rupture strain FRP (LRS-FRP) or hybrid LRS-FRP and conventional glass FRP (GFRP). LRS-FRP are manufactured out of polyethylene naphthalate (PEN) and polyethylene terephthalate (PET) obtained from recycled plastics. Hence, they are much cheaper and environment-friendly than conventional GFRP or carbon FRP (CFRP). LRS-FRPs has high tensile rupture strain (usually greater than 5%) compared to 1-2% for GFRP and CFRP. This study presents the results of 4 specimens with different confinement ratios to investigate the behavior of …

Torsional Behavior Of Hollow-Core Frp-Concrete-Steel Bridge Columns, Sujith Anumolu, Omar I. Abdelkarim, Mohanad M. Abdulazeez, Ahmed Gheni, Mohamed Elgawady

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents the behavior of hollow-core fiber reinforced polymer-concrete-steel (HC-FCS) column under pure torsion loading with constant axial load. The HCFCS consists of outer FRP tube and inner steel tube with concrete shell sandwiched between the two tubes. The FRP tube was stopped at the surface of the footing and provided confinement to the concrete shell from outer direction. The steel tube was embedded into the footing to a length of 1.8 times to the diameter of the steel tube. The longitudinal and transversal reinforcements of the column were provided by the steel tube only. A large-scale HC-FCS column …

Nonlinear Analysis Of Hollow-Core Composite Building Columns, Mohanad M. Abdulazeez, Mohamed Elgawady

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper numerically investigates the behavior of hollow-core fiber-reinforced polymer-concrete-steel (HC-FCS) building columns under combined axial compression and flexural loadings. The HC-FCS column for buildings consists of an outer circular fiber-reinforced polymer (FRP) tube, an inner square steel tube, and a concrete wall between them. A three-dimensional numerical model has been developed using LS_DYNA software for modeling of large scale HC-FCS columns. The nonlinear FE models were designed and validated against experimental results gathered from HC-FCS columns tested under cyclic lateral loading. The FE results were in decent agreement with the experimental backbone curves. These models subsequently were used to …

The Subject Librarian Newsletter, Engineering And Computer Science, Fall 2017, Buenaventura "Ven" Basco

Libraries' Newsletters

No abstract provided.

Structure Analysis And Governance Strategy Of International Containerized Liner Market Under The Shipping Alliances, Xuming Fan

World Maritime University Dissertations

No abstract provided.

On The Ramberg-Osgood Stress-Strain Model And Large Deformations Of Cantilever Beams, Ronald J. Giardina Jr

LSU New Orleans Theses and Dissertations

In this thesis the Ramberg-Osgood nonlinear model for describing the behavior of many different materials is investigated. A brief overview of the model as it is currently used in the literature is undertaken and several misunderstandings and possible pitfalls in its application is pointed out, especially as it pertains to more recent approaches to finding solutions involving the model. There is an investigation of the displacement of a cantilever beam under a combined loading consisting of a distributed load across the entire length of the beam and a point load at its end and new solutions to this problem are …

Performance Of Mud Mortar Walls Under Seismic Loading, Christian L. Berneking Vi, Santiago Pujol, Prateek Pratap Shah, Lucas Laughery

The Summer Undergraduate Research Fellowship (SURF) Symposium

The inherently brittle nature of unreinforced masonry structures results in poor performance during earthquakes, presenting major hazards to communities. Many of these structures found in Nepal were severely damaged or destroyed during two earthquakes in 2015. The purpose of this project is to test the effect on seismic response of several modifications to stone and mud mortar structures. These structures are common in many areas of Nepal. Two T-shaped stone and mud mortar masonry walls are constructed. The first wall has no modifications and represents current building practices. The second wall uses steel wire mesh as external reinforcement. Each wall …

The Effect Of Reinforcing Bar Bend Radius On The Strength And Behavior Of Knee Joints, Xitong Zhou, Christopher S. Williams, Hwa Ching Wang

The Summer Undergraduate Research Fellowship (SURF) Symposium

The strut-and-tie method (STM) is used by structural engineers to design discontinuity regions of reinforced concrete structures. Using STM, the stress distribution in a concrete member is expressed as a set of struts, ties, and nodes in a strut-and-tie model. These components are then proportioned and evaluated to develop an appropriate design. One type of node that appears in knee joints (i.e., frame corners) subjected to closing moments is referred to as a curved-bar node. Although curved-bar nodes represent a unique concentration of stresses in a structure, little research focused on curved-bar node design has been conducted. In response to …

Hazard Assessment Of Meteoroid Impact For The Design Of Lunar Habitats, Herta Paola Montoya, Shirley Dyke, Julio A. Ramirez, Antonio Bobet, H. Jay Melosh, Daniel Gomez

The Summer Undergraduate Research Fellowship (SURF) Symposium

The design of self-sustaining lunar habitats is a challenge primarily due to the Moon’s lack of atmospheric protection and hazardous environment. To assure safe habitats that will lead to further lunar and space exploration, it is necessary to assess the different hazards faced on the Moon such as meteoroid impacts, extreme temperatures, and radiation. In particular, meteoroids pose a risk to lunar structures due to their high frequency of occurrence and hypervelocity impact. Continuous meteoroid impacts can harm structural elements and vital equipment compromising the well-being of lunar inhabitants. This study is focused on the hazard conceptualization and quantification of …

Buckling Of Cylindrical Shells Under Wind Loading, Tianlong Sun, Eyas Azzuni, Sukru Guzey

The Summer Undergraduate Research Fellowship (SURF) Symposium

Cylindrical shells such as aboveground steel storage tanks are widely used to store gases, chemicals and fuels. Stiffener rings are introduced to prevent cylindrical shells from buckling due to wind loads. The current top wind stiffener design rules used in the USA for such cylindrical storage tanks are specified in API 650. However, the design methodology of top stiffener rings is overly conservative. Therefore, relaxation of the design rules for the top stiffener is investigated in this study. The API 650 mandated top stiffener size was reduced to the same size as the mandated intermediate stiffener ring in this study. …

Post-Earthquake Fire Assessment Of Steel Buildings, Yi Li, Rachel Chicchi, Amit H. Varma

The Summer Undergraduate Research Fellowship (SURF) Symposium

Resilience of structural systems after hazardous events is a crucial concern of building design. An abundance of research has focused on hazards such as seismic and fire separately. This project conducted a multi-hazard study on steel buildings considering both seismic and fire damage. A literature review of the behavior of steel-framed buildings due to fires after earthquakes, known as post-earthquake fires (PEF), is offered. The new PEF methodology, delivered in this study, starts with creating a three dimensional (3D) model of the examined steel building using the finite element method software, ABAQUS. Next, varying intensities of seismic and fire hazards …

Effect Of Moment Gradient And Load Height With Respect To Centroid On The Reliability Of Wide Flange Steel Beams Subject To Elastic Lateral Torsional Buckling, Christopher D. Eamon, Alexander W. Lamb, Kapil Patki

Civil and Environmental Engineering Faculty Research Publications

The reliability of doubly-symmetric wide flange steel beams designed to the AISC Specification for Structural Steel Buildings subjected to elastic lateral torsional buckling was evaluated when considering variation in moment gradient and load height. The analysis considers continuous loads on spans subjected to various end moments with supports that are torsionally fixed and laterally supported, without additional intermediate restraints. Dead load, occupancy live load, and beam resistance random variables were considered. Beam lateral torsional buckling resistance was evaluated from numerical solution of a fundamental differential equation that accounts for the effect of moment gradient and load height. In some cases, …

Spectroscopic Contrast Of Diarylethene Molecules On Octanethiol Monolayer, Arramel Arramel, Tibor Kudernac, Nathalie Katsonis, Bernard Lucas Feringa, Bart Jan Van Wees

Makara Journal of Technology

We present a systematic scanning tunneling microscopy (STM) study of bias-dependent imaging of disulfur diarylethene (2S-DE) molecules on octanethiol (C8) monolayer at room temperature. In a rigid confinement of the C8 matrix, we did not observe any significant variation in the appearance of the 2S-DE. On the contrary, a reversal in the apparent height of the 2S-DE was present when the molecule was situated on a gold vacancy island. We attributed this finding to the presence of a new electronic state that became accessible for a tunneling event. In addition, the C8 surface structure underwent a reversible phase transformation from …

Residual Stress Measurements On The Tig Weld Joint Of 57fe15cr25ni Austenitic Steel For Structural Material Applications By Means X-Ray Diffraction Techniques, Parikin Parikin, Agus Hadi Ismoyo, Riza Iskandar, Arbi Dimyati

Makara Journal of Technology

Measurements of residual stress on the 57Fe25Cr15Ni steel plate with no-filler TIG-welding process were carried out. This work was conducted to determine the nature of weld ability in synthesized steel. The bulks were formed in a dimension of 30x20x7 mm3 to ease data retrieval. Results show that the largest residual stress occurred in the weld metal area, amounting to 82.40 MPa with lattice stretching of 0.18%. Conversely, the values decreased to 65.92 MPa and a stretch of 0.14% in the HAZ area. This residual stress is a tensile stress that can reduce the mechanical strength of the material since it …

An Efficient Palladium-Thiourea Catalysed Heck Cross-Coupling Reaction For Molecular Electronic Interest, Wan M. Khairul, Mohd Shahrul Shahmi Md Shariff, Rafizah Rahamathullah, Adibah Izzati Daud, Mustaffa Shamsuddin, Siti Kamilah Che Soh

Makara Journal of Technology

The synthesis and utilization of C-C bonds formation are concerned about the key steps for the building of several conducting molecular electronics involving many asymmetric catalysts approached, which is an essential task that most researchers would ignore in preparing these materials to enhance the production yield of cross-coupling materials. Despite the enormous progress, there still remains a great demand for economic and practicable cross-coupling processes involving ultra-low catalyst loadings with high turnover numbers due to the employment of conventional metal catalyst. Thus, there has been an excessive interest to cultivate non-phosphine palladium catalysts for excellent achievement of activity, stability, and …