Since many materials have low tensile strength and different strength and stiffness properties in two orthogonal directions, the analysis of structures made from them becomes more difficult. This paper presents a simplified approach for the ultimate load analysis of such orthotropic panels subjected to lateral loading. Initially, the simplified approach was developed for brickwork panels that not only have low tensile strength but exhibit different strength and stiffness orthotropies. At failure, these panels develop fracture lines very similar to the yieldlines in ductile plates, so that there has been a great temptation to apply yieldline analysis1,3-6, which is really inappropriate and does not fully explain test results. This is understandable, since it is difficult to imagine fully plastic behaviour in a brittle material like brickwork. Invariably, yieldline analysis7 overestimates the failure pressure6,9. A simplified method based on fracture lines is proposed, which could very well be applied to any brittle material having both strength and stiffness orthotropies. B.P. Sinha
The paper describes a theoretical investigation into the collpase behaviour of the support region of an unstiffened rectangular steel box girder. The results were obtained from a finite-element computer program written for the large-deflection elasto-plastic analysis of 3D plate assemblages. Plasticity is treated using llyushin’s yield criterion. R.S. Puthli, W.J. Supple and M.A. Crisfield
This paper describes the stiffness method of solution of prismatic and tapering beams of various common sections with allowance for shear deformation, and compares the results with those obtained from other analyses. A method of treating heavily stiffened joints and conditions of support other than those applied on the neutral axis is then given, and this is extended to the solution of deep frames exhibiting such conditions. Several examples of stiffened structures are then solved and the results compared against other solutions. D.J. Just
Field loading tests were carried out on a curved prestressed concrete flyover with a multibox section. The bridge deck was analysed using the ICL program for plane frames and grids. A 1/12 scale prestressed concrete model of the structure was also tested. Comparative study of the results from the three sources indicated that the elastic behaviour of the structure could be predicted by computer analysis or model testing with an accuracy acceptable for design purposes. Destructive test of the model also provided an estimate of the cracking load and the ultimate load of the prototype. H.W. Chung, P.K.K. Lee and D. Ho