Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 9 of 9
Full-Text Articles in Engineering
Seismic Behavior Of Composite Bridge Columns, Mohanad M. Abdulazeez
Seismic Behavior Of Composite Bridge Columns, Mohanad M. Abdulazeez
Doctoral Dissertations
“This study investigates experimentally and numerically the seismic behavior of large-scale hollow-core fiber-reinforced polymer-concrete-steel (HC-FCS) innovative bridge columns as a sustainable approach to endure and rapidly recover from natural disasters such as earthquakes. The HC-FCS column consisted of a concrete shell sandwiched between an outer fiber-reinforced polymer (GFRP) tube and an inner steel tube to provided continuous confinement for the concrete shell along with the height of the column. The columns have a slender inner steel tube with diameter-to-thickness (Ds/ts) ratios ranged between 85 to 254. Each steel tube was embedded into the footing, while the …
A New Thickness-Based Accelerated Aging Test Methodology For Resin Materials: Theory And Preliminary Experimental Study, Yanlei Wang, Xue Zhang, Gaochuang Cai, Baolin Wan, Danièle Waldmann, Yuan Qu
A New Thickness-Based Accelerated Aging Test Methodology For Resin Materials: Theory And Preliminary Experimental Study, Yanlei Wang, Xue Zhang, Gaochuang Cai, Baolin Wan, Danièle Waldmann, Yuan Qu
Civil and Environmental Engineering Faculty Research and Publications
This paper proposes a novel accelerated test method based on the thickness of resin materials. This method is to overcome the adverse influence of high temperature on the reliability of experimental results of the accelerated tests widely adopted in the current practice. To verify the proposed thickness-based accelerated method (ThAM), an experimental investigation was conducted focusing on the water absorption and tensile properties of epoxy resin. The results suggest that the existing temperature-based accelerated method (TAM) cannot be applied when the test temperature is high as in this case the degradation mechanism of materials is probably changed. The acceleration factor …
Bio-Inspired Helicoidal Composites: 3d Printing And Experiments, Michael E. Jones, Pablo Zavattieri, Nobphadon Suksangpanya
Bio-Inspired Helicoidal Composites: 3d Printing And Experiments, Michael E. Jones, Pablo Zavattieri, Nobphadon Suksangpanya
The Summer Undergraduate Research Fellowship (SURF) Symposium
Materials that are impact resistant enough for personal protection in sports, transport, and combat are not also lightweight, strong, tough, and impact tolerant. Nature can provide inspiration for novel materials that can meet these needs. The hierarchical composite of the stomatopod’s, or mantis shrimp’s, dactyl club has been shown to have high impact resistance and damage tolerance due to its helicoidal fiber reinforcement(1,2). Analyzing helicoidal composites of different pitch angles (angles between adjacent rows of fibers) under quasi-static, displacement-controlled loading has provided insights into the fracture mechanisms of the composite structure and how they affect the macroscopic properties of the …
Reliability-Based Optimization Of Fiber-Reinforced Polymer Composite Bridge Deck Panels, Michel D. Thompson, Christopher D. Eamon, Masoud Rais-Rohani
Reliability-Based Optimization Of Fiber-Reinforced Polymer Composite Bridge Deck Panels, Michel D. Thompson, Christopher D. Eamon, Masoud Rais-Rohani
Civil and Environmental Engineering Faculty Research Publications
A reliability-based optimization (RBO) procedure is developed and applied to minimize the weight of eight fiber-reinforced polymer composite bridge deck panel configurations. The method utilizes interlinked finite element, optimization, and reliability analysis procedures to solve the weight minimization problem with a deterministic strength constraint and two probabilistic deflection constraints. Panels are composed of an upper face plate, lower face plate, and a grid of interior stiffeners. Different panel depths and stiffener layouts are considered. Sensitivity analyses are conducted to identify significant design and random variables. Optimization design variables are panel component ply thicknesses while random variables include load and material …
Structural Design Of Hollow Extruded Wpc Sheet Piling, Melissa Kahl
Structural Design Of Hollow Extruded Wpc Sheet Piling, Melissa Kahl
Electronic Theses and Dissertations
In marine environments, materials are exposed to a number of harsh environmental factors. Traditional retaining wall materials experience severe degradation as a response to these factors. To address these degradation issues, wood plastic composite (WPC) materials can be used in marine sheet pile applications. WPC materials are both lightweight and durable. This research focuses on developing a sheet pile design that utilizes the material benefits of extruded wood plastic composites with a voided z section sheet pile geometry. The objectives are to develop a more efficient structural design in terms of both material and geometry as compared to the polyvinylchloride …
Stabilization Of Residual Soil With Rice Husk Ash And Cement, Hilmi Mahmud
Stabilization Of Residual Soil With Rice Husk Ash And Cement, Hilmi Mahmud
Hilmi Mahmud
Stabilization of residual soils is studied by chemically using cement and rice husk ash. Investigation includes the evaluation of such properties of the soil as compaction, strength, and X-ray diffraction. Test results show that both cement and rice husk ash reduce the plasticity of soils. In term of compactability, addition of rice husk ash and cement decreases the maximum dry density and increases the optimum moisture content. From the viewpoint of plasticity, compaction and strength characteristics, and economy, addition of 6-8% cement and 10-15% rice husk ash is recommended as an optimum amount. © 2004 Elsevier Ltd. All rights reserved.
Damage Mechanics Of Composite Materials Using Fabric Tensors, Ziad N. Taqieddin
Damage Mechanics Of Composite Materials Using Fabric Tensors, Ziad N. Taqieddin
LSU Master's Theses
The major objective of this work is to relate continuum damage mechanics introduced through the concept of fabric tensors to composite materials within the framework of classical elasticity theory. A model of directional data-damage mechanics for composite materials is formulated using fabric tensors. In addition, a general hypothesis for damage mechanics is postulated. It is seen that the two available hypotheses of elastic strain equivalence and elastic energy equivalence may be obtained as special cases of the postulated general hypothesis. This general hypothesis is then used to derive the sought relationship between the damage tensor for composite materials and the …
Fatigue And Fracture Of The Frp-Wood Interface: Experimental Characterization And Performance Limits, Yong Hong
Fatigue And Fracture Of The Frp-Wood Interface: Experimental Characterization And Performance Limits, Yong Hong
Electronic Theses and Dissertations
A performance-based material evaluation methodology was developed to qualify FRP composite reinforcement bonded to glulam structural members for highway bridge applications. The objectives of this thesis are: a) to implement and correlate two methods to evaluate the fatigue and fracture performance of FRP-wood interfaces with associated performance limits; and b) to provide data and recommendations necessary to develop performance-based material specifications. The first method is based on evaluating the apparent shear strength in a single-lap shear test by fatigue tension loading. The second method is based on evaluating the interface fracture toughness in Mode I or opening-mode using fracture mechanics. …
The Effect Of Cutout Dimensionality On The Collapse Characteristics Of Cylindrical Composite Shells Of Varying Thickness, John C. Del Barga
The Effect Of Cutout Dimensionality On The Collapse Characteristics Of Cylindrical Composite Shells Of Varying Thickness, John C. Del Barga
Theses and Dissertations
This study involved a numerical and experimental investigation of the (geometric instability of graphite/epoxy cylindrical panels with free vertical edges undergoing axial compression. Symmetric quasi-isotropic laminates with five different size centralized cutouts, were investigated for two axial lengths of panels and three thicknesses. The study compared experimental data to results from SHELL, a geometrically nonlinear finite-element program which incorporates a parabolic transverse shear strain distribution through the thickness. The research verified that the SHELL program will provide good predictions of the collapse characteristics of a panel with large cutouts of varying dimensions undergoing large displacements and rotations. The best correlation …