Reinforced Earth Structures to Relieve Walls of Earth Pressure
Earth pressure on walls or concrete retaining structures can reach significantly high values for high structures. The reduction of earth pressure results in a reduced stress on these structures. The concept described in this paper is to reduce the earth pressure by means of wrap back geotextile reinforced earth structures (GRE). GRE structures are a well established construction method. By means of these walls the earth pressure can be reduced to zero, leaving a gap in between wall and GRE. The paper presents two case studies, where wrap back walls have been used behind walls to reduce the earth pressure.
For this application the deformation behaviour of the GRE is very important. Some examples are given, showing the huge capacity of GRE in load bearing combined with small deformation. Deformation measurements of laboratory tests as well as on executed projects are shown. At the end of the paper the benefit of an earth pressure elimination resp. reduction is shown on a virtual example.
GRE walls are capable to bear great loads with low deformation. This can be seen in the presented measurement results of the real-scale test as well as the instrumented bridge abutment. Two elected case studies were presented where GRE structures have been used to reduce the earth pressure on the main building such as an 14 m high wall of an office building as well as 9 m high oversteep (110°) slender concrete wall of an ecoduct. A parameter study shows, that the total costs of a 6 m high retaining (concrete) structure or an abutment can be reduced by about 50% due to the effect of earth pressure elimination by using a GRE structure.