Matching Items (6)
Description
This study focuses on implementing probabilistic nature of material properties (Kevlar® 49) to the existing deterministic finite element analysis (FEA) of fabric based engine containment system through Monte Carlo simulations (MCS) and implementation of probabilistic analysis in engineering designs through Reliability Based Design Optimization (RBDO). First, the emphasis is on experimental data analysis focusing on probabilistic distribution models which characterize the randomness associated with the experimental data. The material properties of Kevlar® 49 are modeled using experimental data analysis and implemented along with an existing spiral modeling scheme (SMS) and user defined constitutive model (UMAT) for fabric based engine containment simulations in LS-DYNA. MCS of the model are performed to observe the failure pattern and exit velocities of the models. Then the solutions are compared with NASA experimental tests and deterministic results. MCS with probabilistic material data give a good prospective on results rather than a single deterministic simulation results. The next part of research is to implement the probabilistic material properties in engineering designs. The main aim of structural design is to obtain optimal solutions. In any case, in a deterministic optimization problem even though the structures are cost effective, it becomes highly unreliable if the uncertainty that may be associated with the system (material properties, loading etc.) is not represented or considered in the solution process. Reliable and optimal solution can be obtained by performing reliability optimization along with the deterministic optimization, which is RBDO. In RBDO problem formulation, in addition to structural performance constraints, reliability constraints are also considered. This part of research starts with introduction to reliability analysis such as first order reliability analysis, second order reliability analysis followed by simulation technique that are performed to obtain probability of failure and reliability of structures. Next, decoupled RBDO procedure is proposed with a new reliability analysis formulation with sensitivity analysis, which is performed to remove the highly reliable constraints in the RBDO, thereby reducing the computational time and function evaluations. Followed by implementation of the reliability analysis concepts and RBDO in finite element 2D truss problems and a planar beam problem are presented and discussed.
ContributorsDeivanayagam, Arumugam (Author) / Rajan, Subramaniam D. (Thesis advisor) / Mobasher, Barzin (Committee member) / Neithalath, Narayanan (Committee member) / Arizona State University (Publisher)
Created2012
Description
The Prestige Worldwide Resort and development area will be constructed to the east of Scottsdale Rd and North of the 101 loop. The development area is composed of 442.58 acres of land within 9 parcels. Zoning for this development area consists of commercial, recreational, golf course, residential, and water/wastewater treatment. The main feature of the development area is a luxury resort to be located at the southwest corner of Legacy Blvd and Hayden Rd. The resort includes a large pond over which the entrance road traverses. The resort also includes an 18-hole golf course located just north of Legacy Blvd. The proposed residential area is to the east of Hayden Rd on the northern half of the site. Along the northeastern border of this residential area are APS, SRP, and Bureau of Reclamation easements. A recreational area in the form of a park is proposed to the east and west of the southern portion of N Hayden Rd on the site. The southeast corner or the site is reserved for water and wastewater treatment. The southwest corner of the site is for commercial use with an additional recreational/sporting area just to the north of this commercial area. The key feature of the resort is its luxurious eight-story hotel along with two other hotel buildings that accommodate tourists who are visiting Scottsdale. The main hotel includes 210 rooms to provide enough housing for these tourists and acquire more attraction to Scottsdale. The composition of the hotel consists of the first floor being the lobby and a recreational area. The other floors each contain 30 rooms, 3 elevators, and a staircase. Surrounding the hotel is a parking lot for the hotel guests and people attending events hosted at the hotel. Regarding the hotel specifications, two different alternative designs were produced to determine the ideal steel member type, concrete reinforcement, and the steel frame layout. The final hotel design was determined by which alternative had the lowest structural response from loading and cost effective.
ContributorsCastro, Cesar Aaron (Author) / Fox, Peter (Thesis director) / Templeton, Stephanie (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Tall building developments are spreading across the globe at an ever-increasing rate (www.ctbuh.org). In 1982, the number of ‘tall buildings’ in North America was merely 1,701. This number rose to 26,053, in 2006. The global number of buildings, 200m or more in height, has risen from 286 to 602 in the last decade alone. This dissertation concentrates on design optimization of such, about-to-be modular, structures by implementing AISC 2010 design requirements. Along with a discussion on and classification of lateral load resisting systems, a few design optimization cases are also being studied. The design optimization results of full scale three dimensional buildings subject to multiple design criteria including stress, serviceability and dynamic response are discussed. The tool being used for optimization is GS-USA Frame3D© (henceforth referred to as Frame3D). Types of analyses being verified against a strong baseline of Abaqus 6.11-1, are stress analysis, modal analysis and buckling analysis.
The provisions in AISC 2010 allows us to bypass the limit state of flexural buckling in compression checks with a satisfactory buckling analysis. This grants us relief from the long and tedious effective length factor computations. Besides all the AISC design checks, an empirical equation to check beams with high shear and flexure is also being enforced.
In this study, we present the details of a tool that can be useful in design optimization - finite element modeling, translating AISC 2010 design code requirements into components of the FE and design optimization models. A comparative study of designs based on AISC 2010 and fixed allowable stresses, (regardless of the shape of cross section) is also being carried out.
The provisions in AISC 2010 allows us to bypass the limit state of flexural buckling in compression checks with a satisfactory buckling analysis. This grants us relief from the long and tedious effective length factor computations. Besides all the AISC design checks, an empirical equation to check beams with high shear and flexure is also being enforced.
In this study, we present the details of a tool that can be useful in design optimization - finite element modeling, translating AISC 2010 design code requirements into components of the FE and design optimization models. A comparative study of designs based on AISC 2010 and fixed allowable stresses, (regardless of the shape of cross section) is also being carried out.
ContributorsUnde, Yogesh (Author) / Rajan, Subramaniam D. (Thesis advisor) / Neithalath, Narayanan (Committee member) / Mobasher, Barzin (Committee member) / Arizona State University (Publisher)
Created2016
Description
Motorcycles must be designed for safety and long operation. Front suspension systems must in turn be safe and able to operate for long service lives. Challenges to achieving safe and long service lifetimes include designing components (rims, axles, forks, etc.) to withstand various loading conditions not just once but numerous times as a matter of fatigue life. An already developed CAD model of a motorcycle suspension was taken and optimized for various loading conditions. These conditions included static loading, braking, cornering, and wheelie and front impact loads. In all cases, front impact load was the critical loading condition when FEA in SolidWorks Simulation was conducted for the components. All components were then optimized to handle the impact load by changing geometry until safety factors of 4.0 ± 0.25 were achieved. Components were then analyzed for fatigue life, with all steel and magnesium components having infinite predicted fatigue lives and all aluminum components having fatigue lives predicted with corrected S-N curves created for up to 500 million loading cycles. The design was optimized with all components becoming improved for stress compliance, with room for improvement existing in both defining loads for analysis and developing more accurate and rigorous fatigue life models.
ContributorsOrth, Trentten (Author) / Nam, Changho (Thesis director) / Chen, Yan (Committee member) / Barrett, The Honors College (Contributor) / Engineering Programs (Contributor)
Created2023-05
Description
One of the fundamental aspects of cellular material design is cell shape selection. Of particular interest is how this selection can be made in the context of a realistic three-dimensional structure. Towards this goal, this work studied the stiffness response of periodic and stochastic lattice structures for the loading conditions of bending, torsion and tension/compression using commercially available lattice design optimization software. The goal of this computational study was to examine the feasibility of developing a ranking order based on minimum compliance or maximum stiffness for enabling cell selection. A study of stochastic shapes with different seeds was also performed. Experimental compression testing was also performed to validate a sample space of the simulations. The findings of this study suggest that under certain circumstances, stochastic shapes have the potential to generate the highest stiffness-to-weight ratio in the test environments considered.
ContributorsSharma, Raghav (Author) / Bhate, Dhruv (Thesis advisor) / Oswald, Jay (Committee member) / Kwon, Beomjin (Committee member) / Arizona State University (Publisher)
Created2019
Description
This Barrett creative project includes the structural design of a coffee shop using recycled shipping containers in Phoenix, Arizona. Repurposing old shipping containers into commercial and residential buildings has become more popular. Even here in Arizona, buildings have already integrated shipping containers into their design. Shipping containers add a unique character to the architectural design of the building and at the same time cut costs of construction due to their low prices. With using the shipping containers as building materials, there is a positive impact on the use of the structures in builds. The uniqueness of using shipping containers is what sparked my interest to design a shipping container coffee shop. For my creative project, I designed the coffee shop using the already structurally sound core of the shipping container to my advantage. However, when adding modifications to the structure, the materials of the structure were analyzed to ensure the design could take the modifications. I have taken my love for structural design, the environment, and coffee and brought it to life. Through this project, I have a better understanding of how much thought goes into designing a building and have a deeper understanding of the codes that structural engineers must follow to design and analyze buildings.
ContributorsWhite, Celine Johanna (Author) / Ward, Kristen (Thesis director) / Chatziefstratiou, Efthalia (Committee member) / Civil, Environmental and Sustainable Eng Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05