3322 BROADWAY COMPASS HEALTH 2025-10-03

Compass Health June 26, 2019 JN 19178 Page 6 We recommend using the following ultimate values for the foundation's resistance to lateral loading: PARAMETER ULTIMATE VALUE Coefficient of Friction 0.50 Passive Earth Pressure 350 pcf Where: pcf is Pounds per Cubic Foot, and Passive Earth Pressure is computed using the Equivalent Fluid Density. If the ground in front of a foundation is loose or sloping, the passive earth pressure given above will not be appropriate. The above ultimate values for passive earth pressure and coefficient of friction do not include a safety factor. FOUNDATION AND RETAINING WALLS Retaining walls backfilled on only one side should be designed to resist the lateral earth pressures imposed by the soil they retain. The following recommended parameters are for walls that restrain level backfill: Active Earth Pressure * 35 pcf Passive Earth Pressure 350 pcf Coefficient of Friction 0.50 Soil Unit Weight 130 pcf Where: pcf is Pounds per Cubic Foot, and Active and Passive Earth Pressures are computed using the Equivalent Fluid Pressures. * For a restrained wall that cannot deflect at least 0.002 times its height, a uniform lateral pressure equal to 10 psf times the height of the wall should be added to the above active equivalent fluid pressure. This applies only to walls with level backfill. The design values given above do not include the effects of any hydrostatic pressures behind the walls and assume that no surcharges, such as those caused by slopes, vehicles, or adjacent foundations will be exerted on the walls. Traffic surcharges can typically be accounted for by increasing the effective height of the shoring wall by 2 feet. It does not appear that there are existing adjacent buildings will exert surcharges on the proposed shoring wall; however, if future buildings are built on the eastern ed_ a of the western allev, thev will surcharge the shorina and should be accounted for is possible. Where sloping backfill is desired behind the walls, we will need to be given the wall dimensions and the slope of the backfill in order to provide the appropriate design earth pressures. Heavy construction equipment should not be operated behind retaining and foundation walls within a distance equal to the height of a wall, unless the walls are designed for the additional lateral pressures resulting from the equipment. The values given above are to be used to design only permanent foundation and retaining walls that are to be backfilled, such as conventional walls constructed of reinforced concrete or masonry. GEOTECH CONSULTANTS, INC,