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