Passive anchors within retaining walls to stabilize volcanic rock slopes in road widening

Abstract

An economical and environmentally-friendly solution to stabilize jointed vertical rock slopes in works of improvement and cross section widening of a local road section in Gran Canaria Island (Spain) is presented in this paper. Due to the mountainous relief of this territory, this road cross over an extremely narrow section between two deep cliffs with vertical rock slopes on jointed phonolitic ignimbrites. The structural solution involves the construction of traditional gravity retaining walls with passive fully-grouted steel bar anchorages within its foundation. The rock mass nailing under the foundation of the retaining walls and even the adjacent rock slopes is also designed. This system combines traditional constructions of high simplicity with modern techniques of rock reinforcement.