6.3 Facing systems

6.3.1 General

6.3.1.1 Facing systems are constructed using a variety of materials, configurations and connections to the reinforcement. Facings exposed to frost should be protected by frost insulation and extra drainage. Typical facing systems are described in Annex A.

6.3.1.2 All facing systems, including connections between facings and reinforcement, shall comply with 6.1.2.

6.3.1.3 The facing system shall enable construction and performance over the design life within specified tolerances of vertical and horizontal alignment.

6.3.1.4 The facing system shall be able to sustain differential settlements required by the design without structural damage to the facing.

6.3.1.5 The suitability of the facing system shall be proven by comparable experience or by tests, proving the serviceability of the system and the durability of the materials used for the design life of the soil nail construction.

6.3.1.6 Connections between the facing and the soil nails shall be capable of transferring load between facing and soil nails, as required by the design, and be able to sustain differential displacement between the facing and soil.

6.3.1.7 Connections between the facing and the soil nails should be capable of compensating misalignment due to installation.

6.3.2 Panels and blocks (normally precast)

6.3.2.1 Concrete panels should comply with EN 206.

6.3.2.2 If the concrete panels are reinforced, steel reinforcement shall comply with EN 10080.

6.3.2.3 The concrete cover of the face in contact with the ground shall be as specified by EN 1992-1-1 for humid environment or other more severe environments.

6.3.3 Sprayed concrete and cast in place concrete

6.3.3.1 The cement used shall conform to EN 197-1 and concrete shall conform to EN 206-1. Sprayed concrete shall conform to EN 14487-1.

6.3.3.2 Admixtures and additives may be used in sprayed concrete.

6.3.3.3 The concrete cover of the face in contact with the ground shall be specified by EN 1992-1-1 for humid environment or other more severe environments.

6.3.3.4 The aggregates used for sprayed concrete shall be stored under cover and shall be well graded to achieve the required spray rate.

6.3.4 Mesh

6.3.4.1 If reinforcing steel mesh is used as facing, it shall be in accordance with EN 10080.

6.3.4.2 If welded wire mesh is used as facing, it shall be constructed of cold-drawn steel wire conforming to EN 10079 and be welded into the finished mesh fabric in accordance with EN 10080.

6.3.4.3 If metallic mesh is galvanised, then it shall comply with EN ISO 1461.

6.3.4.4 If woven wire mesh is used for the facing, it shall be constructed of cold drawn steel wires and the finished product will be woven in accordance with the appropriate European Standards. The coatings on wire shall comply with the minimum requirements of EN 10244 (all parts) and EN 10245 (all parts) for extruded organic coating.

6.3.5 Other materials

6.3.5.1 If geosynthetic materials are used for the construction of a textile facing, they shall comply with EN 13251.

6.3.5.2 All natural and geosynthethic materials shall comply with 6.1.2.

6.4 Drainage systems

All drainage systems, including materials and products, shall comply with 6.1.2.

NOTE Examples of drainage systems are given in 8.5 and in Annex A.