Abstract
This thesis sets down the results and findings of a laboratory and theoretical investigation of reinforced earth with particular reference to reinforced clay. As a prelude to the main body of the work a brief historical review is presented in tandem with a state-of-the-art report. This is followed by four discrete studies. The first invovles a laboratory investigation of both drained and undrained soil-reinforcement bond using both the conventional shear box and a purpose built pull-out apparatus. It was concluded that mesh reinforcement was the most efficient of those reinforcements tested. The second study attempts to define the mechanism of soil reinforcement under both drained and undrained axisymmetric loading. Enhanced strength under drained loading is attributed to the induction, by the reinforcement, of an increased effective confining pressure. Under rapid undrained loading, however, an analogous increase in total confining pressure is found to be associated with a decrease in strength. The penultimate investigation makes use of small scale model walls brought to failure by the application of surcharge. Two analytical methods are presented, the so called "discrete theory" and the "composite theory" which involves the use of an equivalent undrained strength. Both theories and the test results show good agreement. Finally an analytical study is made of the effects of compaction induced lateral earth pressures on both conventional and reinforced earth retaining structures. The veracity of the resulting theory is proven by comparison with data from twelve published case histories. As a closure the main findings of these discrete studies are reiterated in the conclusions.