GNGTS 2023 - Atti del 41° Convegno Nazionale

Session 2.1 GNGTS 2023 Figure 2. Geological formations outcropping at San Salvador city site. The investigated area is located in Santa Tecla along the Balsamo Range (Cordillera del Balsamo) (black square). Table 1. Typical physical-mechanical properties of lithotypes in Fig. 2. Lithotype Unit weight (kN/m 3 ) Friction angle (°) Cohesion (kPa) (s4) Quaternary pyroclastic deposits (Tierra Blanca Joven formation) – very soft soil 11 14 23 (s3a) Quaternary pyroclastic deposits (Tierra Blanca Vieja formation) – soft soil 11 15 30 (s5b)-(s5c) Browny ignimbrites and tuffs (San Salvador formation) – medium soil 15 20 30 (b1) Epiclastites and pyroclastic deposits (Balsamo formation)- medium soil 15 20 30 (c3) Altered pyroclastic deposits (Cuscatlan formation) – hard soil 18 30 60 (c1) Epiclastites and pyroclastic deposits (Cuscatlàn formation) – hard soil 18 30 60