Advanced Methods of Structural Analysis

Chapter 3

Multispan Beams and Trusses

This chapter is devoted to the analysis of statically determinate multispan beams and

trusses, subjected to moving loads. Methods for the generation of beam and trusses,

and the construction of influence lines are discussed. Different types of trusses are

considered; among them are trusses with subdivided panels and some special types

of trusses.

3.1 Multispan Statically Determinate Beams

Multispan hinged beams (Gerber–Semikolenov beams) are geometrically unchange-

able and statically determinate structures consisting of a series of one-span beams

with or without overhangs connected together by means of hinges. The simplest

Gerber–Semikolenov beams are presented in Fig.3.1.

Fig. 3.1 Simplest Gerber–Semikolenov beams

3.1.1 Generation of Multispan Statically Determinate

Hinged Beams

The following rules of distribution of hinges in beams, which have no clamped ends,

provide their unchangeableness and statical determinacy:

1.Each span may contain no more than two hinges.
2.Spans with two hinges must alternate with spans without hinges.
3.Spans with one hinge may follow each other, providing that first (or last) span
has no hinges.
4.One of support has to prevent movement in the horizontal direction.

I.A. Karnovsky and O. Lebed,Advanced Methods of Structural Analysis,

DOI 10.1007/978-1-4419-1047-93,cSpringer Science+Business Media, LLC 2010

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