Ultimate bearing capacity of reinforced saturated ground

Results of model tests on saturated horizontal ground reinforced with geosynthetic reinforcement are analysed using an extended formula for the ultimate bearing capacity ratio (BCR_r). Three components are considered in this formula, namely the bearing capacity ratio induced by the deep-footing mechanism (BCR_d), that induced by the wide-slab effect (BCR_s) and that induced by apparent cohesion (or negative excess pore water pressure) (BCR_c). The calculated BCR_r values for saturated reinforced ground agree well with measured values (BCR_m) within a maximum error of 12·5%. For a low reinforcement placement density (R_d = 2), values of BCR_d can be as high as 70% of the BCR_r, suggesting the importance of the deep-footing effect in a lightly reinforced ground. In the case of high R_d (= 12), the contributions of BCR_s and BCR_c to BCR_r become significant for saturated reinforced grounds.