Abstract
A major component in the cost of new highways in urban areas is the construction of retained cuttings, cut-and-cover tunnels and bridge abutments. TRL's research aimed at achieving more economic but safe designs for retaining structures. This research on both embedded and conventional retaining walls has highlighted the importance of soil stress history, construction sequence and structural form in assessing likely wall performance. Recent findings from pilot scale and field studies, centrifuge modelling, numerical analysis, laboratory and in situ testing are reviewed and the implications on retaining wall design discussed. (A)