|
|
"Breathing" of longitudinally stiffened steel webs subject to repeated partial edge loading
Kutmanová, I. ; Škaloud, Miroslav ; Januš, K.
The aim of the first part of the Prague experimental research on web "breathing" was to look into the effect of the repeated\ncharacter of patch loading on the ultimate limit state of steel plate girder webs fitted with longitudinal ribs. 80 experimental panels were tested to date, the flange size and the position and dimensions of the longitudinal ribs being varied. During the tests, the "breathing" of the girder webs under the action of a cyclic patch load, the initiation and propagation of cracks in the most heavily stressed areas of the webs, and their influence on the "erosion" of the plastic failure mechanisms of the test girders were carefully studied. Final analysis of the data obtained made it possible for the authors to establish the limit fatigue loads, longitudinally stiffened steel plate girders whose thin webs are subject to a repeated partial edge load.
|
|
|
Ultimate load behaviour of longitudinally stiffened steel webs subject to partial edge loading
Kutmanová, I. ; Škaloud, Miroslav ; Januš, K. ; Löwitová, O.
The objective of the contribution is to describe the main results and conclusions of a several years' experimental investigation into the ultimate limit state of steel plate girders whose thin webs were loaded by a partial edge load. Altogether 184 experimental girders were tested, with the following geometrical characteristics of the test girders being varied from girder to girder: (i) the depth-to-thickness ratio of the webs, (ii) the flange size, (iii) the position of\nthe longitudinal rib, (iv) its dimensions and (v) the length of load. Special care was given to a study of (a) the\nstiffeners location and size and (b) the dimensions of the loaded flange upon the progression of plastification, the failure mechanisms and ultimate strengths of the girders tested.
|
|
|
Nonstationary vibrations of rectangular plate excited by concentrated force with linearly variable frequency
Náprstek, Jiří ; Fischer, Ondřej
Many physical and technical problems can be modelled as a rectangular plate with certain edge-supports, loaded by forces with variable frequency (e.g. machines in industrial buildings, electrodynamic systems). Such systems can be solved numerically using finite element method, i. e. solving the system of ordinary differnetial equations in time. In some practical cases of frequency-variation this problem can be solved analytically - the advantage of such a procedure is the objectivity and the possibility of parametric analyses of the problem.
|
host ::
RSS.