2930 MAPLE ST KAISER PERMANENTE Geotech Report 2025-03-07

Geotechnical Engineering Report - Revised lferracon Kaiser Everett Medical Center Everett, Washington December 18, 2019 Terracon Project No. 81195071 GeoReport LATERAL EARTH PRESSURES Design Parameters Structures with unbalanced backfill levels on opposite sides should be designed for earth pressures at least equal to values indicated in the following table. Earth pressures will be influenced by structural design of the walls, conditions of wall restraint, methods of construction and/or compaction and the strength of the materials being restrained. Two wall restraint conditions are shown in the diagram below. Active earth pressure is commonly used for design of free- standing cantilever retaining walls and assumes wall movement. The "at-rest" condition assumes no wall movement and is commonly used for basement walls, loading dock walls, or other walls restrained at the top. The recommended design lateral earth pressures do not include a factor of safety and do not provide for possible hydrostatic pressure on the walls (unless stated). S Surcharge For active pressure movement (0.002 H to 0.004 H) S For at-rest pressure No Movement Assumed Horizontal Finished Grade H Horizontal Finished Grade �p24—p1 Retaining Wall Lateral Earth Pressure Design Parameters Earth Pressure Coefficient for Backfill Uniform Pressure 3,4,5 Effective Fluid Condition ' Type pi (psf) Pressures (psf)2,a'5 Active (Ka) 0.31 (0.31)S (40)H At-Rest (Ko) 0.47 (0.47)S (60)H Passive (Kp) 3.25 --- (400)H (7)H —Active Seismic 6 --- --- (12)H —At-Rest 1. For active earth pressure, wall must rotate about base, with top lateral movements 0.002 H to 0.004 H, where H is wall height. For passive earth pressure,wall must move horizontally to mobilize resistance. Responsive ■ Resourceful ■ Reliable 17