A SIMPLIFIED CALCULATION METHOD FOR SYMMETRICAL LOADING OF A SINGLE-SPAN COMPOSITE STRING STEEL STRUCTURE

The article presents single-span composite string steel structure. The article discusses the calculation method for the single-span composite string structure when the load is symmetrical, while the string and bottom cable act as absolutely flexible elements. It presents the way the displacements and the shear force in the supports are calculated for the distributed and concentrated loads. Calculations with a pre-tensioned string are provided. The results are compared with the results obtained with the finite element method program. The conclusions present the results obtained.

Mechanical Behaviour of Steel-Concrete Twin I-Girder Bridges

<p>Steel-concrete composite twin I-girder bridges have been built a lot in both Europe and Japan, but the lack of redundancy has always been a concern in U.S. and many other countries. In addition, few experimental studies have been performed on the mechanical performance of such bridges, particularly for the intact bridges. On this background, a steel-concrete composite twin I-Girder bridge model was designed according to the current highway bridge design specification in Japan and tested in the laboratory. The static loading tests were performed, and two loading conditions including both symmetrical loading and unsymmetrical loading were applied. Load versus deflection relationships were measured in the loading test, and the failure mode of the test specimen was discussed. The flexural strain development on bottom flanges of two main girders was also reported in this paper to confirm the load transfer between two main girders. In addition, the theoretical results on the basis of the classic theory were also provided to compare with the test results. The comparison indicates that the theoretical analyses can predict the behaviour of the twin I-girder bridges very well in the elastic stage by considering the effective width of the slab. The load transfer paths in such bridges were also discussed on the basis of the test results under un-symmetrical loading.</p>

The Effects of Earthquake on the Cylindrical Tanks

This paper deals with a problem of earthquake of the cylindrical tank. During the seismic event, the load acts in one direction only, i.e. in the direction of earthquake. This load imposes a non-symmetrical loading of a structure. At seismic load of structure of cylindrical tank was used accelerogram. In final part of the paper some crucial results are presented both in a graphical and numerical way.

Analysis of Cylindrical Tanks under the Seismic Load

The paper deals with cylindrical tanks. Structures of this type have been used in hydraulic engineering, e.g. water towers, sewerage plant tanks. In recent years, cylindrical tanks have been also used in biogas management as fermentation and storage tanks.While the standard hydrostatic load acts symmetrically, it evokes the rotary symmetric load. During the seismic event, the load acts in one direction only, i.e. in the direction of earthquake. This load imposes a non-symmetrical loading of a structure. By a combination of individual loads the resulting forces are slightly non-symmetrical.Specific tank has been modeled. In one model, the solution is made using the quasi-static load induced by the hydrodynamic pressure according to the standard EC1998, part 4 [12]. The other model is presented as a calculation using the modal and spectral analyses under the seismic load. At the conclusion, these two solutions have been compared.

Theoretical and Experimental Investigations on Shear Lag Effect of Double-Box Composite Beam with Wide Flange under Symmetrical Loading

ABSTRACTA new type of steel-concrete composite beam with double-box cross-section is proposed in this paper. In order to investigate stress behaviors and deflection characteristics of such composite beam with wide flange considering the shear lag effect, theoretical analysis and experimental study are launched simultaneously. Based on the minimum potential energy principle, governing differential equations in view of the shear lag effect are deduced by energy variational method, and analytical solutions of it's stress and deflection under the effect of symmetrical loading are calculated. The preceding analyses show that relative error is less than 14.71%, with a good agreement, and farther show that this method of theoretical derivation, which is used for analyzing shear lag effect of composite beam with wide flange, has certain reference and guidance.