Nonlinear dynamic behaviour of a saddle form cable net modeled by an equivalent sdof cable net

Vassilopoulou, I; Gantes, CJ

dc.contributor.author	Vassilopoulou, I	en
dc.contributor.author	Gantes, CJ	en
dc.date.accessioned	2014-03-01T02:53:22Z
dc.date.available	2014-03-01T02:53:22Z
dc.date.issued	2011	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/36276
dc.relation.uri	http://www.scopus.com/inward/record.url?eid=2-s2.0-80054819869&partnerID=40&md5=5be7e00b2347aabc6d6c3e82bddc4876	en
dc.subject	Equivalent sdof model	en
dc.subject	Nonlinear dynamic response	en
dc.subject	Saddle form cable net	en
dc.subject	Similarity relations	en
dc.subject.other	Analytical solutions	en
dc.subject.other	Approximate analysis	en
dc.subject.other	Cable nets	en
dc.subject.other	Computational effort	en
dc.subject.other	Computational time	en
dc.subject.other	Degree of freedom	en
dc.subject.other	Duffing oscillator	en
dc.subject.other	Eigen frequencies	en
dc.subject.other	Eigen modes	en
dc.subject.other	Equation of motion	en
dc.subject.other	External loads	en
dc.subject.other	Geometrically nonlinear	en
dc.subject.other	Hyperbolic paraboloids	en
dc.subject.other	Initial conditions	en
dc.subject.other	Jump phenomenon	en
dc.subject.other	Loading frequencies	en
dc.subject.other	Non-linear dynamics	en
dc.subject.other	Non-linear phenomena	en
dc.subject.other	Nonlinear dynamic response	en
dc.subject.other	Response amplitudes	en
dc.subject.other	Response curves	en
dc.subject.other	Saddle form cable net	en
dc.subject.other	SDOF models	en
dc.subject.other	Similarity relations	en
dc.subject.other	Single-degree-of-freedom	en
dc.subject.other	Steady state	en
dc.subject.other	Steady state oscillation	en
dc.subject.other	Subharmonic resonances	en
dc.subject.other	Super-harmonic	en
dc.subject.other	Time history analysis	en
dc.subject.other	Time variations	en
dc.subject.other	Vertical displacements	en
dc.subject.other	Cable supported roofs	en
dc.subject.other	Civil engineering	en
dc.subject.other	Computational methods	en
dc.subject.other	Dynamic models	en
dc.subject.other	Dynamic response	en
dc.subject.other	Earthquakes	en
dc.subject.other	Engineering geology	en
dc.subject.other	Equations of motion	en
dc.subject.other	Modal analysis	en
dc.subject.other	Resonance	en
dc.subject.other	Structural dynamics	en
dc.subject.other	Cables	en
dc.title	Nonlinear dynamic behaviour of a saddle form cable net modeled by an equivalent sdof cable net	en
heal.type	conferenceItem	en
heal.publicationDate	2011	en
heal.abstract	The purpose of this paper is to estimate the geometrically nonlinear dynamic behavior of a saddle form cable net, using an equivalent single-degree-of-freedom model. First, a symmetric simple cable net is assumed, consisting of two crossing cables, considering the vertical displacement of the central node as the only degree of freedom. The equation of motion is found to be similar to the one of the Duffing oscillator with a hardening cubic term. Next, a MDOF symmetric cable net model is considered, with fixed cable ends, having a circular plan view and forming a surface of a hyperbolic paraboloid. Harmonic external loads act vertically on every node of the net, with the same amplitude and time variation. Modal analyses are conducted in order to calculate the linear eigenfrequencies and the corresponding eigenmodes of the network. The nonlinear dynamic response of the cable net is obtained by performing time history analysis. Detecting nonlinear phenomena, such as bending of the response curve, jump phenomena, different response amplitudes according to the initial conditions, superharmonic or subharmonic resonances, demands much computational effort for different load amplitudes and ratios of loading frequency. Based on a method of approximate analysis for prediction of the response of cable nets, the MDOF model is transformed to an equivalent SDOF one, using similarity relations. The analytical solution of the single-degree-of-freedom model can provide, with minimum computational time, the basic information needed for nonlinear dynamic response, i.e. secondary resonances, jump phenomena, dependence on the initial conditions and the exact loading frequency for which the maximum steady state oscillation amplitude is obtained. The comparison between the two models by means of the steady state amplitude of the central node, demonstrates that the behavior of the SDOF model describes satisfactorily the one of the MDOF model, predicting the dominant nonlinear phenomena.	en
heal.journalName	ECCOMAS Thematic Conference - COMPDYN 2011: 3rd International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering: An IACM Special Interest Conference, Programme	en