Flexible slope stabilization systems made from wire mesh in combination with nailing are widely used in practice to stabilize soil and rock slopes. They are economical solutions and a good alternative to measures based on rigid concrete liner walls or massive supporting structures. Apart from designs using conventional steel wire, mesh from high-tensile steel wire is now also available on the market. The latter can absorb substantially higher forces and transfer them into the nailing. Special concepts have been developed for the dimensioning of flexible slope stabilization systems for use on steep slopes in more or less homogeneous soil or heavily weathered loosened rock, as well as fissured and layered rock. In the latter instability is determined by the fissure and layer surfaces. Stabilizations implemented in soil and rock, with and without vegetated face, confirm that these measures are suitable for practical application.
The use of flexible slope stabilization measures has proved its suitability in numerous cases around the world including Switzerland, Germany, Italy, Spain, Poland, North America, South America and South Africa. The open structure of the mesh permits development of a full-surface vegetation face. In most cases for slope stabilization purposes the wire mesh is based on a tensile strength of the individual wires of 400–500 N/mm2. In this case if a nail spacing of say 2.75 m by 2.75 m is used, the mesh is often unable to absorb the driving forces and to transmit them into the nails. The development of a wire mesh made from high-tensile steel wire of a tensile strength of the individual wire of at least 1770 N/mm2 offers new possibilities for an efficient and economical stabilization of slopes. Taking the statics of soil and rock into account serves to dimension the proposed stabilization.
A high-tensile steel wire mesh made out of a steel with a tensile strength of 1770 N/mm2 at least has been developed which is available on the market under the name TECCO®. In standard layout, it is made from a steel wire of 3 mm diameter which has an aluminium-zinc coating for protection against corrosion. The diamond shaped mesh measuring 83 mm × 143 mm is produced by single twisting. The steel wire mesh provides a tensile strength of 150 kN/m. This value represents a minimum guaranteed load or bearing capacity. By tensioning the nail and if possible slightly impressing the spike plates into the ground to be stabilized, the mesh follows the surface contour and is tensioned in the best possible manner. With the slope stabilization system the rows of nails are offset to each other by half a horizontal nail distance. This means that the maximum possible local body liable to break out between the individual nails is limited to a width "a" and a length of "2 × b" (see Figure 2). The staggered layout is shown in Figure 3 for a project in Polymilou, Greece.
