Introduction
Retaining walls have been used for thousands of years; whether in the construction of terraced fields on a steep slope, or a railway cutting through a hill side, a retaining wall is used in some form or another.
This Technical Guidance Note is a description to the various forms of retaining walls that are currently used. It is primarily concerned with structures that retain soil; although many of the aspects described can be translated to retaining other materials such as grain, sand and liquids. The water table will have design implications on the wall, the pressure of which can be alleviated by providing drainage and weep holes, depending on the soil conditions. The aim of this note is to provide you with sufficient familiarity of the various types of retaining wall so that when you encounter them or are developing a retaining wall solution, you will know what options are available.