Vol.2, No 1, 1999 pp. 53-60
UDC 624.072.2:519.6(045)

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SECOND ORDER ANALYSIS OF SPACE BEAM STRUCTURES
Marina Mijalković
Faculty of Civil Engineering and Architecture, Niš, Beogradska 14, Niš, YU

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Abstract. The subject of this paper is the analysis and design of space beam structures based on second-order theory using "exact" strain method. The advantage of this procedure over the "simplified" strain method is in including the influence of  axial forces in the members on deformations of the structure, which is significant for some types of structures, such as: multistory frames, arches, suspension structures, etc.
On the basis of theoretical consideration presented in this paper, the general program for PC has been developed. The program is intended for static analysis – the determination of nodal displacements and member forces of all types of space structures, as well as plane structures, which consist of members subjected to various external load. The first order analysis, as a spatial case of second order analysis is contained, too.
Using this program one suspension bridge was analyzed in the paper.

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PRILOG PRORAČUNU KONSTRUKCIJA
PRIMENOM TEORIJE DRUGOG REDA Predmet ovog rada je analiza i proračun uticaja kod prostornih linijskih nosača po linearizovanoj Teoriji drugog reda po tačnoj metodi deformacije. Prednost ovog postupka u odnosu na približnu metodu deformacije je što obuhvata i uticaj normalnih sila na deformaciju sistema, koji je značajan kod nekih konstrukcija kao što su višespratni ramovi, lukovi, lančani sistemi i dr.
Na bazi teorijskih razmatranja prikazanih u radu razvijen je jedan generalni program za proračun statičkih i deformacijskih veličina po linearizovanoj teoriji drugog reda svih tipova linijskih nosača u prostoru, kao i u ravni. Uključena je i teorija prvog reda, kao specijalni slučaj teorije drugog reda.
U radu je analiziran primer lančanog mosta koji je primenom ovog programa obrađen.