1318 W MUKILTEO BLVD 2016-01-01 MF Import

Wrought Corporation August 11, 2006 JN 06287 Page 8 fluid with a unit weight of 30 or 40 pounds per cubic foot (pc� depending on whether the shoring is temporary or permanent. Traffic surcharges can typically be accounted for by increasing the effective height of the shoring wall by 2 feet. Slopes above the shoring walls will exert additional surcharge pressures. These surcharge pressures will vary, depending on the configuration of the cut slope and shoring wall. Wa can provide recommendations regarding slope surcharge pressures when the preliminary shoring design is completed. It is important that the shoiing design provides sufficient working room to drill and install the soldier piles, without needing to make unsafe, excessively steep temporary cuts. Cut slopes should be planned to intersect the backside of the drilled holes, not the back of the lagging. Lateral movement of the soldier piles below the excavation level will be resisted by an ultimate passive soil pressure equal to that pressure exerted by a fluid with a density of 450 pcf. No safety factor is included in the given value. A typical safety factor of 1.2 or 1.5 should be included in this value to obtain an allowable pressure depending on whether the shoring is temporary or permanent. This soil pressure is valid only for a level excavation in front of the soldier pile; it acts on two times the grouted pile diameter. Cut slopes made in front of shoring walls significantly decrease the passive resistance. This includes temporary cuts necessary to install internal braces or rakers. The minimum embedment below the floor of the excavation for cantilever soldier piles should be equal to the height of the "stick-up." The vertical capacity of soidier piles to carry the downward component of the tieback forces will be developed by a combination of frictional shaft resistance along the embedded length and pile end-bearing. Where: (i) psf is pounds per square foot The above values assume that the excavation is level in front of the soldier pile and that the bottom of the pile is embedded a minimum of 10 feet below the floor of the excavation. For the pile end-bearing to be appropriate, the bottom of the drilled holes must be cleaned of loosened soil. The shoring contractor should be made aware of this, as it may affect their installation procedures. The concrete surrounding the embedded portion of the pile must have su�cient bond and strength to transfer the veRical load from the steel section through the concrete into the soil. GEOTECH CONSULTANTS. INC.