PREFAILURE BEHAVIOR OF REINFORCED SOIL

This paper deals with the elastic-plastic analysis of fibre-reinforced soil that is treated as a macroscopically homogeneous composite mater ial. First, the theory of such a material is briefly described. The th eory allows for straightforward determination of the initial yield sur face of reinforced soil. The initial yield surface is defined as a sur face, in the macrostress space, on which either the soil or the reinfo rcement first becomes plastic the second constituent being in. an elas tic state. Further loading of the composite causes the regrouping of m icrostresses in both constituents up to the stage at which the second constituent becomes plastic. The points corresponding to such states f orm, in the macrostress space, the global yield surface for reinforced soil. The global yield surface can be determined analytically only in special cases. In a general case it can be determined by numerical in tegration of incremental equations describing an elasto-plastic range of the composite's behaviour. The global yield surface is determined f or various sets of initial data. The results are compared with the lim it surface defined by the rigid-plastic model of reinforced soil. Conc lusions of practical importance are drawn.