In this paper, a technology enabling the optimization of topology truss or frame structures with genetic algorithms is presented. It has been shown that due to huge number possible variants global solution similar problems exhaustive search feasible only for systems possessing small numbers d.o.f. s (usually until 10 nodes). These can be solved in reasonable time by algorithms. The modified algorithm suggested, where repair genotype, instead some constraint used. numerical examples original...

In this paper, topology and shape optimization of truss or frame structures is discussed. The starts from a structure, into which finite number nodesare set; all the nodes are connected together by trusses in possible variants. Unfit variants system rejected. Two alternative ways compared: starting initial structure with larger nodes, smaller but additional obtained topology. solved original modified genetic algorithm, giving better results comparison classical algorithm. Instead further...

Present paper describes the facilities of composite material properties identification technique using specimen vibration tests, genetic algorithms, finite elements analysis and shape optimization. In process elastic constants in a numerical model is updated so that output from code fits results testing. Main problem analysed this Poisson's ratio worst determined characteristic due to its low influence on eigenfrequencies. It shown it possible increase by choosing specific test...

Abstract A numerical method combining finite element analysis and a hybrid genetic algorithm is proposed to inversely determine the elastic constants from vibration testing data. As verified composite material specimens, repeatability accuracy of inverse determination are confirmed, it also proves that concept effective workable. Moreover, three different sets assumptions reduce five independent four do not make clear difference on obtained results by method. In addition, obtain robust...

The aim is to investigate ways of increasing the efficiency grillage optimization. Following this general aim, two well‐known optimization methods, namely Genetic Algorithm (GA) and Simulated Annealing (SA), were compared using some standard medium size (10 15 piles) examples. objective function was maximal vertical reactive force at a support. Coordinates piles variables. SA wins applied real‐life problem (55 by parallel computations performed powerful cluster. New element comparison with...

The mathematical models and different solution algorithms for global optimization of pile placement schemes in grillage-type foundations are presented: the local search from a quasioptimal by Branch-and-Bound algorithm genetic algo-rithms. maximum absolute value vertical reactive force arising at either support is to be minimized. op-timization problem nonlinear nonconvex. objective function supplied “black box” finite element program. Comparison techniques reveals potential this type...

The aim of the article is to choose algorithms suited for optimal placement piles in real grillages by performing experimental comparison different global optimization algorithms. includes several algorithms: random search, metaheuristics (simulated annealing and genetic algorithm) local combined with search. are compared using results pile schemes 10 practical small-to-medium scale data obtained from design bureaus. best have been achieved simulated nonlinear algorithm NEWUOA heuristic...

The paper addresses one engineering design prob-lem, the optimization of pile placement schemes under grillage-type foundations. Aim is to find scheme where number piles minimal and reactive forces at all do not exceed given allowable reaction. This global problem solved here using simulated annealing algorithm which proved be most promising algorithms for grillage optimization. Optimization real-life grillages PC requires usually unacceptably long engineer-ing practice computation time,...

The mathematical models and solution algorithms for optimization of grillage-type foundations are presented. Optimization grillage is based on separate beams comprising grillage. Minimising maximum in absolute value vertical reactive force, bending moment, reaction-bending moment together sought a beam. All these problems non-linear, therefore solved iteratively changing each iteration the structure shape to better neighbouring shape. Solution this requires three steps: finite element...

A technique for simultaneous topology, shape, and sizing optimization of tall guyed masts is presented in this paper. The typical scheme telecommunication that are triangular plan supported by a certain number guys’ levels examined. objective function the total mass mast, including guys. mast structure optimized self-weight wind loading evaluated according to Eurocodes. nonlinear behaviour simplified idealizing guys as approximate boundary conditions mast. comparison solution with results...

The article concerns optimization of network arch bridges. This is challenging problem involving even for conventional scheme bridge the identification some topological parameters as well shape configurations and all sizing structural members, seeking minimum weight. Optimal sought tuning a large set design diverse character: type hanger arrangement, number hangers, their inclination angles placement distances, rise, etc. Mathematically, mixed-integer constrained global solved employing...

In this paper, a technology enabling to optimize the topology of truss or frame structures with genetic algo-rithms is presented. The objective function total mass structure elements. Constrains consist equilibrium equations and conditions on stresses in elements: cannot exceed allowable value must be above some threshold value. values are calculated package ANSYS. Genetic algorithm interface implemented C++. Exchange data between ANSYS C++ goes through temporary files. Numerical examples

The article presents the technique for simultaneous topology, shape and sizing optimisation of tall guyed masts under wind loadings self-weight using simulated annealing. objective function is mass mast structure including guys, while set design parameters may consist up to 10 different nature. constraints are assessed according Eurocodes include local global stability constraints, limitations on slenderness in elements, strength constraints. proposed covers three independent parts:...

The paper analyzes the performance of parallel global optimization algorithm, which is used to optimize grillage-type foundations. algorithm obtained by using automatic parallelization tool. We describe briefly layer structure Master–Slave Template library and present a detailed mathematical formulation application problem. Experiments are done on homogeneous computer cluster 7 IBM machines RS6000. results experiments presented.

Modified genetic algorithm with special phenotypes' selection and crossover operators default specified rules is proposed in this paper thus refusing the random crossover. The suggested operator enables wide distribution of genes best phenotypes over whole population. During crossover, newest population additionally individuals two previous populations are involved. effectiveness modified shown numerically on real-life global optimization problem from civil engineering - optimal pile...

In this paper, a new simplified version of the Bayesian Approach to coordinate global optimization (BAcoor) is compared with well-known algorithms. BAcoor some method multi-dimensional by applying sequence one-dimensional optimizers starting from best points obtained previous optimization. The globality one-dimension search controlled only parameter ε. element that observation are defined explicit formulas. other similar methods, such as [8, 15, 16, 10, 11], performed numerical techniques...

This data article provides a series of 220 optimal parameter sets steel radial network arch pedestrian bridge schemes. Each set includes 10 design parameters for two-dimensional frame: the rise, number hangers, their (variable) spread and central angles, dimensions arch, girder, hangers. Additionally, solutions are provided different initial conditions such as constant hanger given ratio values between rise span, diameters, condition hangers' verticality. These related to research...

Santrauka Suformuluoti pamatų sijyno optimizavimo uždavinių matematiniai modeliai, pasiūlyti jų sprendimo algoritmai. Išspręsti trys uždaviniai: lenkimo momentų, atraminių reakcijų minimizavimo ir bendras momentų uždavinys. Statikos uždavinys sprendžiamas baigtinių elementų metodu. Panaudotas paprastas dviejų mazgų lenkiamo strypo elementas su dviem laisvumo laipsniais mazge. Jautrumo atramų postūmiams analizė atlikta analitiškai. Optimizavimui taikytos tiesinio matematinio programavimo...

Steady-case thermal analysis plays an important role in dimensioning control systems for spacecrafts and aircrafts. Usually a trial error approach is used based on engineering judgement experience. When models become complex or there are conflicting requirements, however, it becomes harder engineer to gain insight as which design decisions will lead better results. Numerical optimization, the other hand, could provide more robust of spacecraft aircraft models. In this paper, we suggest...

A geometric algorithm for the packing of a given sequence polydispersed circular particles into containers regular polygon shape is suggested. The proposed aims twofold goal: obtaining maximum density and following prescribed homogeneity distribution laws particles. When seeking density, obtained further optimized by several heuristic stochastic optimization algorithms. objective function supplied “black-box” routine, which can either determine best possible place in each particle or allow...