Structural optimization using evolutionary algorithms (original) (raw)

Comparison of evolutionary-based optimization algorithms for structural design optimization

In this paper, a comparison of evolutionary-based optimization techniques for structural design optimization problems is presented. Furthermore, a hybrid optimization technique based on differential evolution algorithm is introduced for structural design optimization problems. In order to evaluate the proposed optimization approach a welded beam design problem taken from the literature is solved. The proposed approach is applied to a welded beam design problem and the optimal design of a vehicle component to illustrate how the present approach can be applied for solving structural design optimization problems. A comparative study of six population-based optimization algorithms for optimal design of the structures is presented. The volume reduction of the vehicle component is 28.4% using the proposed hybrid approach. The results show that the proposed approach gives better solutions compared to genetic algorithm, particle swarm, immune algorithm, artificial bee colony algorithm and differential evolution algorithm that are representative of the state-of-the-art in the evolutionary optimization literature.

Structural design in the framework of cascade evolutionary optimization

1. Abstract In structural sizing optimization problems the aim is to minimize an objective function under certain constraints. The design variables of the optimization problem are generally discrete and belong to certain discrete sets. In the context of the present work the design set is implemented and efficiently treated as a database that contains the required geometric properties for all design variables considered in the optimization process. The proposed computational procedure, which is termed as multi-database cascade optimization, is implemented using an evolutionary optimization algorithm and the results prove that it can be an effective tool for handling large design spaces in the context of sizing optimization problems. 2. Keywords: evolutionary algorithms, sizing optimization, cascade, discrete databases.

Evolutionary Algorithm For Structural Optimization

1999

A hybrid rank-based evolutionary algorithm that takes advantage of a-priori problem specific information and operates on a high cardinality heuristic genetic representation is presented in this paper. A rank based fitness statement combined with generationally dependant penalty exponents is proposed to condition the seven components of the fitness statement so they participate fairly during the evolutionary process. Translocation crossover and

An evolutionary-based optimization algorithm for truss sizing design

Vietnam Journal of Mechanics, 2016

In this paper, the optimal sizing of truss structures is solved using a novel evolutionary-based optimization algorithm. The efficiency of the proposed method lies in the combination of global search and local search, in which the global move is applied for a set of random solutions whereas the local move is performed on the other solutions in the search population. Three truss sizing benchmark problems with discrete variables are used to examine the performance of the proposed algorithm. Objective functions of the optimization problems are minimum weights of the whole truss structures and constraints are stress in members and displacement at nodes. Here, the constraints and objective function are treated separately so that both function and constraint evaluations can be saved. The results show that the new algorithm can find optimal solution effectively and it is competitive with some recent metaheuristic algorithms in terms of number of structural analyses required.

Advances in structural optimization

Advances in Engineering Software, 2010

The objective of this study is to investigate the efficiency of various Evolutionary Algorithms (EAs), such as Evolution Strategies (ESs) and Genetic Algorithms (GAs), when applied to large-scale sizing optimization problems. ESs and GAs imitate biological evolution in nature and combine the concept of artificial survival of the fittest with evolutionary operators to form a robust search mechanism. The proposed methods are compared with a conventional mathematical programming (MP) method. A hybrid methodology, namely GAs-MP is also proposed in order to combine the advantages of both methods. The numerical tests presented demonstrate the computational advantages of the proposed methods, which become more pronounced in large-scale optimization problems.

Application of Evolutionary Optimization in Structural Engineering

IFIP Advances in Information and Communication Technology, 2009

Practical optimization methods including genetic algorithms are introduced, based on evolutionary computing or soft computing. Several application examples are presented to demonstrate and discuss the efficiency and applicability of the described methods.

A Genetic Evolution Algorithm for Structural Optimization

The application of genetic algorithm-based methodology for the structural design is presented in this study. The genetic algorithm is used to design prestressed concrete beams (PCB). The target objective in this method is to obtain set of optimal geometrical dimensions of symmetrical I-beam cross section. Additionally, the amount of pre-stressing steel is optimized. Post-tensioned prestressed beam with a single duct of parabolic shape is considered in the application. Several parameters are studied including the effect of the span length considering different loading cases. The performance constraints are adopted according to the ACI 318/95 Building Code provisions [1]; including the flexural stresses, the ultimate moment capacity of the section with respect to cracking moment, the maximum crack width, the immediate deflection and the long term deflection in addition to the side constraints. The results are presented and compared; several design charts are developed and presented. The present study showed the promising capabilities of the genetic algorithm in optimal designs, and showed the practicability of the genetic algorithm for different structural optimization problems.

Computationally Efficient Techniques for Structural Optimization

2000

Abstract. The objective of this paper,is to investigate the efficiency of combinatorial optimization methods and in particular algorithms based on evolution strategies, when incorporated,into structural optimization problems. Evolution strategies algorithms are used either on a stand-alone basis, or combined with a conventional mathematical programming technique. Furthermore, the structural analysis phase is replaced by a neural network prediction for the computation,of

Multi-database exploration of large design spaces in the framework of cascade evolutionary structural sizing optimization

Computer Methods in Applied Mechanics and Engineering, 2005

In discrete sizing optimization of truss and frame structures the design variables take values from databases, which are usually populated with a relatively small number of cross-section types and sizes. The aim of this work is to allow the use of large-size databases in discrete structural sizing optimization problems, in order to enrich the set of design variable options and increase the potential of achieving high-quality optimal designs. For this purpose, the concept of coarse database is introduced, according to which smaller-size versions of an appropriately ordered large database can be constructed. This concept is combined with the idea of cascading, which allows a single optimization problem to be tackled with a number of autonomous optimization stages. Under this context, several coarse versions of the same full-size database are formed, in order to utilize a different database in each cascade stage executed with an evolutionary optimization algorithm. The first optimization stages of the resulting multi-database cascade procedure make use of the coarsest database versions available and serve the purpose of basic design space exploration. The last stages exploit finer databases (including the original full-size database) and aim in fine tuning the achieved optimal solution. Based on the reported numerical results, multi-database cascading proves to be an effective tool for the handling of large databases and corresponding extensive design spaces in the framework of discrete structural sizing optimization applications. Ó 2005 Published by Elsevier B.V.

Structural Design Optimisation Using Genetic Algorithms and Neural Networks

This paper relates to the optimisation of structural design using Genetic Algorithms (GAs) and presents an improved method for determining the fitness of genetic codes that represent possible design solutions. Two significant problems that often hinder design optimisation using genetic algorithms are expensive fitness evaluation and high epistasis. Expensive fitness evaluation results in slow evolution and occurs when it is computationally expensive to test the effectiveness of possible design solutions using an objective function. High epistasis occurs when certain genes lose their significance or value when other genes change. Consequently, when a fit genetic code has an important gene changed this can have a dramatic effect on the fitness of that genetic code. Often the reduction in fitness results in failure of the genetic code being selected for reproduction and inclusion in the next generation. This loss of evolved genetic information can result in the solution taking consider...