Ballistic soil nailing

Ballistic soil nails are fired directly into the ground using a compressed air launcher which can propel 38 mm diameter steel nails 6 m or more into the soil to be reinforced. Elements of design and construction of ballistically nailed works are considered and the versatility of the technique illustrated through four examples. The first relates to a steep cut to be retained by a reinforced soil modular block slope where temporary works construction gave rise to instability and the modular block slope was replaced by a ballistic nailed slope. The second details slope stabilisation works combining the use of bored piles, conventional reinforced soil walls and ballistic soil nailing. The third involves remedial works to a secondary road, supported by fill on sidelong ground, where the natural slope had been undercut by a stream at its toe. The final example recounts remedial work to a deep shaft, lined with concrete segments, which suffered a serviceability failure during construction.