Wyniki wyszukiwania - BazTech

1

Application of the Generalized Stochastic Perturbation Method in cable structures analysis

Szafran J.

Structure and Environment

|

2015

|

Vol. 7, no. 2

61--71

EN

The main focus of this paper is the presentation of the capabilities of the numerical analysis dedicated to cable structures affected by random parameters. The main tool of the analysis carried out is the Generalized Stochastic Perturbation Method. It allows to determine numerically the statistical data for horizontal reaction of a single cable with respect to random parameters, such as the modulus of elasticity of rope or the magnitude of loading. Central probabilistic moments of structure responses are calculated using the analytical approach to the determination of horizontal reactions of a single cable supported with a stochastic perturbation technique. The moments were obtained for random Young modulus and loading. In the analyses, computer algebra system MAPLE v.13 was applied. The computer application described in the paper may be utilized in reliability analysis of much more complex cable structures such as masts, girders, roofs or cable supported bridges.

2

Analiza stateczności stalowych wież telekomunikacyjnych o parametrach losowych

Kamiński M., Szafran J., Świta P.

Zeszyty Naukowe. Budownictwo / Politechnika Łódzka

|

2011

|

Z. 63

151-165

PL

Tematem pracy jest zastosowanie uogólnionej metody perturbacji stochastycznej do wyznaczenia probabilistycznych momentów obciążenia krytycznego stalowych wież telekomunikacyjnych. Obciążenia te wyznacza się przy pomocy Stochastycznej Metody Elementów Skończonych dla losowo określonych parametrów geometrycznych przekroju i modułu Younga stali konstrukcyjnej. Wykorzystując metodę funkcji odpowiedzi, oblicza się wartości oczekiwane i odchylenia standardowe sil krytycznych, które można wykorzystać przy montażu kolejnych urządzeń nadawczych, a także - do wyznaczania wskaźników niezawodności tych konstrukcji. Przeprowadzana analiza ma również na celu weryfikację wrażliwości konstrukcji na parametry projektowe przyjęte jako zmienne losowe.

EN

The main aim of this paper is the stability analysis of the steel telecommunication tower with random parameters using the Generalized Stochastic Finite Element Method. The Taylor expansion with random coefficients of nth order is used to express all random state parameters and to determine the basic probabilistic characteristics of the critical load. The Response Function Method assists to determine higher order partial derivatives of the structural response instead of the Direct Differentiation Method employed widely before and sufficient to assure high quality of the resulting moments. The magnitude of the critical force is examined in terms of random Young modulus as well as of the main structural members diameter to show how much extra load (in the new telecommunication equipment) may be applied in the future at this tower to prevent the structural failure. Further application of this methodology is seen in the reliability analysis and reliability-based topology optimization of such steel structures.

3

Reaction-diffusion problems with Random parameters using the generalized stochastic finite difference method

Kamiński M.

Journal of Applied Computer Science

|

2011

|

Vol. 19, nr 2

31-45

EN

The main idea here is to demonstrate the new stochastic discrete computational approach consisting of the generalized stochastic perturbation technique based on the Taylor expansions of the random variables and, at the same time, classical Finite Difference Method on the regular grids. As it is documented by the computational illustrations, it is possible to determine using this approach also higher probabilistic moments and to provide full hybrid analytical-discrete analysis for any random dispersion of input variables unlike in the second order second moment technique worked out before. A numerical algorithm is implemented here using the straightforward partial differentiation of the reaction-diffusion equation with respect to the random input quantity; all symbolic computations of probabilistic moments and characteristics are completed by the computer algebra system MAPLE.