In this study, a unified optimal design approach is proposed for the design of skeletal dome structure (SDS). Thus, this study has three objectivities, i) presenting the emergence of proposed design integrity, ii) applying the proposed optimal design approach for the design optimization geometrically nonlinear SDS with both ellipse and sphere-shaped forms considering both the shape, size and topology-related design variables, iii) determining the dominant design criteria in the design of SDS. In this framework, the design of SDS is optimized thereby minimizing its entire weight and joint displacements and maximizing its member forces at the same time. The design constraints are borrowed from the provisions of American Petroleum Institute (API RP2A-LRFD) specification. A multi-objective optimization algorithm (MOA) named Pareto Archived Genetic Algorithm (PAGA), as an optimization tool is integrated by an automatic dome generating tool. Therefore, the novelty of this study comes from being the first attempt to obtain the optimal design in a way of integrating both member and joint-related design constraints by the geometrically nonlinear structural analysis. Consequently, it is displayed that that the proposed optimal design approach facilitates to determine an appropriate optimal design through a tradeoff analysis for designers depending on their preferences. The design concepts concerned with buckling, axial stress, combination of axial & bending, and yielding have the higher dominant effects in the optimal design of SDS. Furthermore, it is also demonstrated that the inclusion of diagonal members into the design of SDS provides a reduction in the violation of dominant design constraints.
The lattice girder, members of which are constructed by use of ready profiles with tubular cross-sections, has a simple but an effective structural framing form. In this regard, this study proposes to optimize the design of tubular lattice girders i n a way of minimizing its entire weight and joint displacement and maximizin g its load-carrying capacity considering the design codes of API RP2A-LRFD. As an optimization tool, a multi-objective optimization methodology named pareto archived genetic algorithm (PAGA) was utilized. The search capability of PAGA was improved by invol ving a designer module for automatically creation of a lattice girder form. The improved PAGA has a big responsibility of increasing the convergence degree of optimal designs against the stability problem. Furthermore, the content of this study is enriched by evaluating the computing efficiency of PAGA with respect to several multi-objective optimization algorithms. Consequently, the improved PAGA achieves to explore the optimal lattice girder designs with the higher convergence, diversity and capacity degr ees. Therefore, the proposed optimum lattice girder design tool is recommended for the designers due to its capability of obtaining a wide range of promising designs.
Fatigue damage occurs in steel joints exposed to repeated loads during their service life. Even if the design of lattice tubular structures that make up the steel skeletal structures is carried out according to certain regulations, the evaluations for determining the most critical fatigue damage in these structures are limited. Moreover, the discrete geometric configurations of trusses make it difficult to accurately predict fatigue damage. In this study, fatigue analyzes were performed on the planar T-joint sample with two different methods and under different boundary and loading conditions. Three-dimensional finite element models and three-dimensional welded joint detail were created to perform more accurate analysis. As a result, it has been determined that the fixed type support increases the fatigue life due to the increase in rigidity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.