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Using Thermodynamics To Evaluate Stationary Phase Polarity In Gas Chromatography- A New Look, Hetal R. Rana

Seton Hall University Dissertations and Theses (ETDs)

Abstract

Gas chromatography is a separation method in which the components of a sample partition between a gaseous mobile phase (carrier gas) and a solid or liquid stationary phase. The stationary phase is usually a polymer coated or chemically bonded to a solid support on the column wall and its function is to separate different components, based on their relative vapor pressure and their intermolecular interactions with the stationary phase. If the analyte polarity is similar to the stationary phase polarity, then the retention time increases because the intermolecular interactions are stronger and if the polarities are different then the …

The Glass House, Ricardo Villanueva, Emma Placek, Jacob Keller, Jorge Rios

Architectural Engineering

A collaboration of Architects and Architectural Engineers to design a unique depiction of the 50x50 Glass House with Miesian Architectural appeal.

Structural Behavior Of Circular Geopolymer Concrete Filled Fiber Reinforced Polymer (Frp) Tube Columns Internally Reinforced With Frp Bars Under Different Loading Conditions, Junaid Ahmad

University of Wollongong Thesis Collection 2017+

Sustainable development is a global goal to address the climate change due to increased greenhouse emissions. The construction industry is the largest industry in the world and cement is the most widely used material. Cement industry is a major contributor in carbon dioxide (CO2) emissions. In recent years, geopolymer concrete (GPC) has emerged as a sustainable alternative to ordinary Portland cement concrete (OPC). The GPC not only eliminates the use of cement, but also utilizes the industrial waste materials like fly ash (FA) and ground granulated blast furnace slag (GGBFS).

Steel reinforced concrete (RC) structures are commonly used in the …

Optimum Mix Design And Structural Behaviour Of Steel Fibre Reinforced Geopolymer Concrete Cured Under Ambient Condition, Nabeel Abed Farhan

University of Wollongong Thesis Collection 2017+

Concrete is one of the most common construction materials in the world. The primary material used in the production of concrete is cement. However, the manufacture of cement is associated with greenhouse gas emissions which cause global warming. Hence, there is a need to develop other types of concrete that does not contain cement in order to maintain environmental sustainability. Geopolymer concrete as green concrete without cement has been investigated as a viable alternative to traditional concrete for reducing the adverse environmental impact. Fly ash (FA) and ground granulated blast furnace slag (GGBS) are the most popular industrial by-product materials …

Columns Of Some Kind : Kinetic, Structural, Formal, Periodic & Interactive Elements Of Architecture, Jhanani Palanismay

Masters Theses

Architects and designers exist within the matrix of artificial intelligence and animate tools, therefore we are faced with the task of examining what it means to ‘humanize’ architecture and foster a tangible and intangible interaction with the spaces we inhabit. The poetics of architecture is now interpreted through the degree of engagement with technological advancements.

As an architectural element, the ubiquitous column exists within the substrate of floor and ceiling. In designing an animate column while retaining structural integrity, an opportunity is created for dialogic feedback between the user and the built environment, thereby activating different spatial conditions.

The generation …

Fea Of Carbon Composite As A Substitute For Steel (A992) In Case Of Square Or Rectangular Hollow Cross-Sections As Beams And Columns, Pradeep Ganesh Pai

Mechanical and Aerospace Engineering Theses

Improvement to an existing design is an ongoing and never-ending process in every field. The improvement can be in a myriad of areas like an increase in strength, reduction in weight, stiffness to a loading condition and so on. The way it is achieved can range from changing the properties of the material used by incorporating various manufacturing processes or by using an alternative material which can sustain the same loading conditions or for that matter, work better than the existing material. Composite materials like Carbon Fiber, Glass Fiber or Kevlar Fiber reinforced plastics, to name few, are being used …

Structural Behaviour Of Circular High Strength Concrete (Hsc) Columns Reinforced With Glass Fibre-Reinforced Polymer (Gfrp) Bars And Helices Under Different Loading Conditions, Hayder Alaa Hasan

University of Wollongong Thesis Collection 2017+

Steel reinforcement in reinforced concrete structures is vulnerable to corrosion, especially in marine structures or structures located in aggressive areas or moist environments. The corrosion of the steel reinforcement causes huge maintenance cost and in some situations leads to severe damages in the concrete structures.

Fibre Reinforced-Polymer (FRP) bars have several advantageous properties, including, light weight, high tensile strength, and electromagnetic neutrality, in addition to the corrosion resistance. The FRP bars became ideal replacements for the conventional steel bars in reinforcing concrete structures that require such characteristics. However, FRP bars are not recommended to reinforce concrete columns. This is because …

Partial Material Strength Reduction Factors For Aci 318, Tong Zhang

Electronic Thesis and Dissertation Repository

The strength reduction factors, phi, defined in ACI 318-14 for different structural actions and elements lead to inconsistent results. This study proposes partial material strength reduction factors for concrete, phi_c, and reinforcing steel, phi_s, that yield similar design strengths and more consistent reliability indices. Three structural actions are investigated: moment; shear; and, combined moment and axial force. The first-order, second-moment method is used to compute reliability indices for moment and shear, and Monte Carlo simulation is used for combined moment and axial force. The statistical parameters assumed for the professional factor for shear strength significantly impact …

Circular Rc Columns Partially Confined With Frp, Sahar Y. Ghanem

Theses and Dissertations--Civil Engineering

Wrapping reinforced concrete (RC) columns with Fiber Reinforced Polymer (FRP) composites is effective in increasing their capacity. The current state of art concentrates primarily on fully wrapped RC columns and few studies dealt with partially wrapped columns. The majority of the studies did not account for the influence of the existing steel reinforcement on the column’s behavior. Other studies estimated the total confinement pressure as the sum of the confinement pressure due to the external FRP jacketing and due to the internal transverse steel reinforcement. Few models dealt with the coupled effect of the confinement from steel and partial FRP …

Behaviour Of Fibre-Reinforced Polymer (Frp) Tube Reinforced Concrete (Ftrc) Specimens Under Different Loading Conditions, Ali Qasim Luaibi Al-Baali

University of Wollongong Thesis Collection 1954-2016

This study provides an experimental investigation of the behaviour of fibre-reinforced polymer (FRP) tube reinforced concrete (FTRC) specimens under different loading conditions. Four groups of 16 specimens with diameter of 200 mm and height of 800 mm were cast and tested. Specimens in the first group (Group REF) which is reference group were reinforced with longitudinal steel bars and steel helixes. Specimens in the second group (Group ST) were reinforced with intact glass FRP tubes. Specimens in the third group (Group ST-G) were also reinforced with intact glass FRP tubes. In addition, polymer grid was embedded into the concrete cover …

Behaviour Of Circular Concrete Columns Reinforced With Gfrp Bars And Gfrp Helices, Hogr Karim

University of Wollongong Thesis Collection 1954-2016

Glass Fibre Reinforced Polymer (GFRP) bar has emerged as a preferable alternative to steel bar in Reinforced Concrete (RC) members in harsh, corrosive, and coastal environments. This is particularly because steel bars may corrode in such environments and may cause damage and deterioration of RC members. FRP bars are noncorrosive and possess high tensile strength to weight ratio. In spite of their high tensile strength, FRP bars are not recommended to reinforce concrete columns because of their low compressive strength and low modulus of elasticity in comparison to the steel bars. The behaviour of FRP bar reinforced concrete (FRPRC) columns …

Structural Behaviour Of Frp Tube Reinforced Concrete (Ftrc) Columns, Weiqiang Wang

University of Wollongong Thesis Collection 1954-2016

FRP tube reinforced concrete (FTRC) column is a novel hybrid concrete column proposed in this thesis. In the FTRC column, FRP tube is placed into the concrete to act as internal reinforcement of the column. Two types of FTRC columns have been investigated. Type I FTRC column is reinforced with perforated FRP tube. Type II FTRC column is reinforced with intact FRP tube, and polymer grid is embedded into the concrete cover to prevent the premature spalling of concrete cover. Both types of FTRC columns are expected to achieve excellent durability under harsh environments as well as superior performance under …

The Design Of Moment Connections Between Rectangular Hollow Sections, Billy Allen

Theses

Steel portal frames in the construction industry typically comprise 1 and H sections. The design procedures for the connections in these frames (base, eaves and apex) are well established. This research is based on using rectangular hollow sections as the column and rafter members.

The eaves connection of a rectangular hollow section pitched portal frame is investigated in this report and includes a literature review of various experimental research relating to moment connections between rectangular hollow sections.

Three eaves joints were considered in this research. The joints were physically tested in the laboratory and a finite element analysis carried out. …

Numerical Modelling And Performance Of Reinforced Concrete Members Under Fire Condition, Mohamed Moftah

Digitized Theses

A thermo-mechanical finite element model is developed to study the behaviour of reinforced concrete columns and beams exposed to fire. Two different analyses are included in this model. A three-dimensional nonlinear transient heat conduction analysis that takes into account the variation of the thermal properties of concrete with temperature is first conducted. The temperature profile resulting from the exposure of a reinforced concrete member to fire is determined by the heat transfer analysis and is then exported to a stress analysis model. A special nonlinear fibre frame element is used in this model. The stress analysis incorporates a material model …

Methods To Improve Bond On Frp Wrapped Piles, Andy Schrader

USF Tampa Graduate Theses and Dissertations

Fiber Reinforced Polymer (FRP) sheets can provide incredible structural strength while weighing only a fraction as much as steel. When applied to piles the FRP provides strengthening through both concrete confinement and tensile reinforcement. Mainly used in structural repair, its application is relatively simple in theory. However, many factors(some avoidable, some not) can interfere with the bond between FRP and concrete. When this bond is interrupted the strength of the repair becomes compromised.This thesis examines 2 new methods of improving FRP bond to concrete piles during the time the resin is curing. These methods are compared using 3 types of …

Site Response Projections For Deep Sediment Columns And Earthquake Microzonation For The Las Vegas Basin, Ying Liu

UNLV Retrospective Theses & Dissertations

Deep sediment columns play a significant role in defining surface response to earthquakes. For the Las Vegas basin (Nevada, U.S.), the basin sediments are capable of amplifying ground motions by a factor of up to 5 to 10 with respect to motions recorded at near-rock sites at the edges of the basin, over the period range 0.3 to 5 sec; A one-dimensional (1-D) equivalent-linear model is used to study the impact of sediment columns on surface response. The 1-D model is optimally parameterized through iterative assessment to select the depth to halfspace so that the projected response spectrum best matches …

Evaluation Of Fire Resistance Of Plastering Applied To Reinforced Concrete, Engy M Samy Serag

Archived Theses and Dissertations

Concrete is one of the most resistant construction materials to heat and fire. It is known to retain heat for a relatively long time, thus limiting crack propagation from penetrating deeply. Furthermore, it can be repaired if exposed to fire for a limited time. However it loses its strength dramatically when exposed to elevated temperatures for long duration. With the increase in the use of concrete in structures, a demand arises to assess the fire resistance of concrete structural members and to develop means of improving the fire characteristics of these elements. One of the methods to increase the fire …

Non-Linear Evaluation Of Concrete-Filled Steel Tubular Columns, Mohammad Hassan Shams

Dissertations

Concrete-filled steel tubular (CFT) columns have become increasingly popular in structural applications due to their high strength, high ductility, and large energy absorption capacity. These structural properties are the result of integral behavior of the concrete core and the steel tube. This research provides an analysis of the interaction of the concrete core and the steel tube in CFT columns.

While there have been many experimental studies of CFT columns, there has been no analytical work modeling the confining effect of the steel tube on the concrete core. Furthermore, current design procedures tend to underestimate the ultimate strengths of CFTs …

Behavior Of Concrete And Slender Reinforced Concrete Columns Under Cyclic Axial Compression With Bidirectional Eccentricities, Byong Youl Bahn

Dissertations

A rational analysis of reinforced concrete (R/C) structures requires satisfactory modeling of the behavior of concrete under general loading patterns. The behavioral characteristics of concrete dominantly depends upon its load history. For the study of concrete behavior, parametric study and experimental investigation into the behavior of concrete under load history of random cycles are performed. Through parametric study, the applicability of the previous concrete models is examined and a physically motivated modeling for the cyclic stress-strain relationships is proposed. The present modeling of concrete under general cyclic loading is initiated to provide substantial applicability, flexibility of mathematical expressions and furthermore …

Behavior Of Biaxially Loaded Concrete-Encased Composite Columns, Pedro Ricardo Munoz

Dissertations

The theory of nonlinear behavior of biaxially loaded short and slender composite columns is used to study the load-deformation and moment-curvature of four pin-ended composite column specimens tested under axial compressive load and biaxial bending moments in a single curvature. The accuracy of the test results is verified by comparison with analytical results obtained by a method of analysis that includes the nonlinear material properties of concrete and steel and covers the ascending and descending branches of the linear segmented column specimen. A computational method is presented to model the analytical behavior of the biaxially loaded composite column. Its validity …

Behavior Of R/C Columns Under Nonproportional Variations In Axial And Lateral Loads, Kaniz Fatema Ahsan

Theses

The study on the behavior of reinforced concrete columns subjected to the motion of earthquake suggests that the structure may experience nonproportional variations in axial and lateral forces. In order to assess the capacity of a reinforced concrete structure under nonproportional loadings, an analytical model is developed using the fiber modeling technique.

The method is based on detailed analytical description of the geometry and material properties used in evaluating the behavior of the critical regions rather than a simplified and predefined set of hysteresis rules. The present study has two principal components of investigation. First, the analyses are done at …

Behavior Of High Strength Concrete And Slender Reinforced Concrete Columns With And Without Steel Fibers, Lin Showmay Hsu

Dissertations

A series of compression tests are conducted on 3 in. by 6 in. cylindrical specimens using a modified testing method that give the complete stress-strain behavior for both plain and fibrous high strength concretes with or without tie confinements. The volume fractions of fiber in the concrete are 0%, 0.5%, 0.75%, and 1.0%, respectively. Empirical equations are proposed herein to represent the complete stress-strain relationships of high strength and high strength fibrous concretes with compressive strength exceeding 10,000 psi. Various parameters are studied and their relationships are experimentally determined. The comparison between the experimental and analytical results shows to have …

Three-Dimensional Beam-Columns, Mohammad Hassan Shams

Theses

This thesis explores several special cases of three-dimensional beam-columns and suggests that the method of finite differences can be used when a solution of general case is required. The thesis begins with a review of the three-dimensional beam-column equations and then shows how these equations can be used to generate the member stiffness matrix for the nonlinear analysis of three-dimensional frames. Examples are included which discuss the differences between the analytical and numerical solutions.

Behavior Of Square And L-Shaped Slender Reinforced Concrete Columns Under Combined Biaxial Bending And Axial Compression, Wen Hu Tsao

Dissertations

A numerical analysis was developed to evaluate the complete load-deflection and moment-curvature relationships for square and L-shaped slender reinforced concrete columns subjected to biaxial bending and axial load. This computer model can be used for any cross section geometry and material properties of normal concrete. The analysis was based on a deformation control and both the ascending and descending branches of curves can be studied. The finite difference method was introduced to calculate the deflections which satisfy the compatibility equations. Six square slender columns and eight L-shaped slender columns were tested to compare their experimental load-deformation results with the analytical …

Daily Columns In The Contemporary Egyptian Press, Thomas Kerop Gorguissian

Archived Theses and Dissertations

No abstract provided.

Behavior Of Thin-Walled Channel Shaped Reinforced Concrete Columns Under Combined Biaxial Bending And Compression, Subash Yalamarthy

Theses

Next to rectangular, circular and L shapes, Channel section may be the most frequently encountered reinforced concrete columns since they can be used as box wall for elevators. Nevertheless, information about the load deformation behavior is not generally available to structural engineers. Most of the investigations have been emphasized on the ultimate strength of column sections under combined biaxial bending and axial compression and the resulting interaction surface. No attention is paid to load deformation behavior.

Current code provisions do not provide adequate guidelines for assessing the strength and ductility of biaxially-loaded reinforced concrete columns. Therefore, this investigation is aimed …

Behavior Of L-Shaped Reinforced Concrete Columns Under Combined Biaxial Bending And Compression, Amar Shah

Theses

Combined biaxial and axial compression for L-shaped reinforced concrete short columns is a common design Problem. Current code, provisions and the available design aids do not offer an insight into the determination of strength and ductility of biaxially loaded reinforced concrete column. An experimental and analytical investigation of the moment-deformation behavior of biaxially loaded L-shaped short columns were undertaken. Four 1/2 scaled specimens were tested till failure. Moment-curvature and load-deflection curves were developed from the experimental and the analytical results. The analytical results were obtained using a computer program developed by Hsu (1). From the investigation it is deduced that …

Behavior Of Tee-Shaped Reinforced Concrete Columns Subjected To Biaxial Bending And Axial Compression, Antoun Romanos Nader

Theses

The investigation deals with the effect of eccentric loading on the moment-curvature relationship of reinforced concrete tee columns.

The test program consisted of two series of tee-shaped reinforced concrete columns, loaded biaxially at constant angle from the principle axes. Their end conditions were assumed to be pinned-ended.

Loads, at constant rate, were gradually applied until failure. At each loading stage, measurements were made for the strains and deflections at the mid span section.

The experimental and theoretical results of the load- deformation and moment-curvature were compared and found that the analytical approach proposed by Hsu is applicable to irregular sections …

Comparative Analysis Of Seven Lifestyles Sections: March 8-14 1981, Virginia Vickers Braun

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.

A Numerical Solution For Three Dimensional Beam Columns In The Elastic Region, Hamid Reza Afghan

Dissertations and Theses

The three differential equations describing the behavior of the beam columns in three dimensions are derived and presented in finite difference form. A computer model is developed to solve the simultaneous equations in the elastic regions and predict the member behavior.

The computer program is checked by comparing the results obtained from the program with data from other investigators, and classical analytical techniques.