Finite Strip Analysis of the Dynamic Response of Highway Bridges Subject to Moving Loads
Author : Malcolm James Short
Publisher :
Page : 206 pages
File Size : 47,1 MB
Release : 1978
Category : Bridges
ISBN :
Author : Malcolm James Short
Publisher :
Page : 206 pages
File Size : 47,1 MB
Release : 1978
Category : Bridges
ISBN :
Author : Abdulkarim Hassan Ali
Publisher :
Page : 0 pages
File Size : 38,1 MB
Release : 2000
Category :
ISBN :
The dynamic analysis of highway bridges is very complex because of the interaction between the moving vehicle load and the bridge response. Analytical methods such as beam theory and orthotropic plate theory are applicable only to simple structures and highly simplified moving vehicle load models. The beam theory is applicable only to long and narrow bridges since it neglects the effect of transverse flexibility of the bridge. The orthotropic plate theory is only applicable to slab bridges under simple vehicle load models as complex vehicle models render the differential equation of equilibrium difficult or impossible to solve. The finite element method is a very powerful and versatile technique which can be applied to deal with any specific configuration of bridge structure, supports and vehicle load models. However, the efficiency of the method needs to be improved because the finite element solutions usually require too much computer time, too large core storage and too much data input. In addition to these deficiencies, in order to simulate the local of the moving concentrated wheel loads the finite element mesh should be refined in both directions. The finite strip method has already proven to be the most efficient numerical technique for the static analysis of bridges. In fact the method is even more efficient for dynamic analysis of bridges. The structure can be divided into a number of finite strips. In each strip the displacement components at any point are expressed in terms of the displacement parameters of nodal lines by means of simple polynomials in the transverse direction and a continuously differentiable smooth series in the longitudinal direction. Thus, the number of dimensions of the analysis is reduced by one. The minimum number of degrees of freedom along a nodal line in the finite strip method is equal to twice times the number of terms used in the series and this is normally much less than that for finite element method, which requires a minimum of three times the number of nodes along the same line. Hence the size and the bandwidth of the matrices are greatly reduced, and consequently it can be handled by personal computers and solved in much shorter time. In this study the finite strip method is applied to dynamic analysis of simply supported single span slab bridges, slab-on girder bridges, box girder bridges and multi-span bridges by using various vehicle load models. Harmonic analysis of beams is covered in Chapter Two as an introduction for the finite strip method. A FORTRAN computer program capable of analyzing all the topics covered in this thesis is also developed.
Author : Herbert S. Suer
Publisher :
Page : 188 pages
File Size : 41,66 MB
Release : 1955
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Author :
Publisher :
Page : 400 pages
File Size : 46,72 MB
Release : 1948
Category : Mechanics, Applied
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Author : John M. Biggs
Publisher :
Page : 250 pages
File Size : 14,93 MB
Release : 1958
Category :
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Author : Shabnam Darjani
Publisher :
Page : 164 pages
File Size : 13,45 MB
Release : 2013
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Through the development and usage of high-strength materials, the design of more flexible bridges is unavoidable. It is assumed that limiting a bridge static deflection would control the excessive vibration caused by more flexible design. However, results of prior studies indicate that deflection limits do not necessarily address bridges vibrational issue. This dissertation addresses the parameters affecting bridge vibration and provides simple equations to compute bridge dynamic acceleration, velocity and displacement in both transient and steady state parts of the vibration. These equations can then be used to control bridges excessive vibration; and provide human comfort and structural performance. A comprehensive analytical study was performed to evaluate dynamic response of bridges under a moving truck load. The effect of bridge dynamic parameters and vehicle moving conditions are investigated, which includes bridge frequency, damping ratio, span length, girders distance, bracing, support conditions, truck speed, load sequence, axle's weight, and number of spans. Bridge and vehicle k-parameters, which represent the number of vibration cycles before the next excitation occurs, are developed to better explain the vibrational behavior of a bridge. The proposed equations include bridge frequency, static deflection for one axle load, and k-parameters. Finally, a case study is presented to highlight the application of the new approach.
Author : Lei Gong
Publisher :
Page : 478 pages
File Size : 35,17 MB
Release : 2008
Category : Box girder bridges
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Author : Cenap Oran
Publisher :
Page : 302 pages
File Size : 39,39 MB
Release : 1961
Category : Bridges
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Author : National Research Council (U.S.). Highway Research Information Service
Publisher :
Page : 980 pages
File Size : 45,32 MB
Release : 1984
Category : Highway engineering
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Author : Paul P. Christiano
Publisher :
Page : 0 pages
File Size : 29,46 MB
Release : 1967
Category : Carnegie-Mellon University
ISBN :