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Table 5.1: Minimum Recommended Factors of Safety for the Design of Soil Nail Walls <br /> Using the ASD Method (1) <br /> Minimum Minimum <br /> Recomm. Recomm. <br /> Limit State Condition Symbol Factors of Factors of <br /> Safety, Static Safety, <br /> Loads Seismic Loads <br /> Overall Overall Stability FSos 1.5(2) .1(6) <br /> Overall Short Term Condition, FSos 1.25-1.33(3) NA <br /> Excavation <br /> Overall Basal Heave FSBH 2.0(4), 2.5(5) 23(5) <br /> Strength— Pullout Resistance FSpo 2.0 1.5 <br /> Geotechnical <br /> Strength — <br /> Geotechnical Lateral Sliding FSI,s 1.5 1.1 <br /> Strength — Tendon Tensile Strength PST 1.8 1.35 <br /> Structural (Grades 60 and 75) <br /> Strength — Tendon Tensile Strength FST 2.0 1.50 <br /> Structural (Grades 95 and 1 50) <br /> Strength — Facing Flexural FSFF 1.5 1.1 <br /> Structural <br /> Strength — <br /> Structural Facing Punching Shear FSFP 1.5 1.1 <br /> Strength — Headed Stud Tensile <br /> Structural (A307 Bolt) FSFH 2.0 1.5 <br /> Strength — Headed Stud Tensile FSFH 1.7 1.3 <br /> Structural (A325 Bolt) <br /> Notes: (1) The limit state and symbol nomenclature differ from that presented in the previous version of <br /> this manual. Many of these changes reflect the move toward using LRFD terminology as <br /> presented in AASHTO(2014). <br /> (2) For non-critical,permanent structures, some Owners may accept a design for static loads and <br /> long-term conditions with FSos= 1.35 when uncertainty is considered to be limited due to the <br /> availability of sufficient geotechnical information and successful local experience on soil <br /> nailing. <br /> (3) This range of safety factors for global stability corresponds to the case of temporary <br /> excavation lifts that arc unsupported for up to 2 days before nails are installed. The larger <br /> value may be applied to critical structures or when more uncertainty exists regarding soil <br /> conditions. <br /> (4) This factor of safety for basal heave is applicable to permanent walls for short-term <br /> conditions. <br /> (5) This factor of safety for basal heave is applicable to permanent walls for long-term <br /> conditions. <br /> (6) The minimum FSos for seismic overall stability should be 1.0,when horizontal seismic <br /> coefficients are used and these were derived from estimated,allowable seismic deformations. <br /> 108 <br /> 18185E Page 22 of 180 <br />