A Review on The Performance of Ring foundations resting on reinforced and unreinforced soil

Abstract

This manuscript presents a literature review of research undertaken on the bearing various parameters and conditions particularly loading types, size of footings, type of soil, bearing capacity factors Nγ, Nq and Nc, in addition to soil reinforcement. Numerous researchers investigated the bearing capacity of the ring foundations noticed that it is affected severely bearing capacity and settlement of ring footings under by the ratio of radius of the ring and the optimum value was 0.4 beyond which the bearing capacity of ring footing decreased under static conditions, different values have been found under dynamic conditions. It is to be acknowledged that most experimental tests were carried out statically mostly with small scale physical model. In contrast, only a few were undertaken with a dynamic test. It was observed that the optimal size and orientation of the reinforcement layer represent the main factors to enhance the bearing capacity and minimize the settlement for the ring footing located on geogrid reinforced sandy soil. In particular, the embedment depth for reinforcement, the space between two-layers, and the size of geogrid equal to (0.3-0.32), 0.32, and (3.5-4.0) of the outer diameter of footing respectively. Furthermore, it was found that the evaluates of bearing capacity factor Nγ, Nq, and Nc strongly affected by the ratio of the radius for both smoothly base and roughly base of the ring footings particularly the factor Nγ, particularly for greater values of the ratio of radius, the value of Nγ is considerably higher for roughly surfaces than that for a smoothly base.