2505 PACIFIC AVE 2018-01-01 MF Import

Sierra Construction Services , Inc. JN 92276 July 1 . 1992 Page 8 additional lateral pressures resulting from the equi pment. Placement and compaction of retaining wall backfill should be accomplished with hand-operated equipment. Retaining Wall eackfill ' eackfill placed behind retaining or foundation walls should be free-draining structural fill containing no organics . This backfill should contain no more than five ' (5) percent silt or clay particles and have no particles greater than four (4) inches in diameter. 7he percentage of particles passing the No. 4 sieve should be berween 25 and 70 percent. Due to their high silt content, if the native ggad soils are used as backfill , a drainage composite, such as Miradrain or Enkadrain, �hould be placed against the retaining walls . The drainage i , , composites should be hydraulically connected to the foundation drain system. The silt soils are unacceptable for retaining wall backfill . The purpose of these backfill requirements is to ensure that the design criteria for the retaining wall ere not , exceeded because of a build-up of hydrostatic pressure behind the wall . The top foot to eighteen inches of the backfill should consist of a relatively impermeable soil or topsoil , or the surface should be peved. The sub- section entitled �ENERAL EARTHWORK AND STRUGT �Rei FI � contains recommendations regardin� placement and compaction of structural fill behind retaining and foundation walls . PAVEMENT AREAS All pavement sections may be supported. ebove competent native soils , or on structural fill placed above native soils . The . existing fill soils should be removed from beneath pevement erees due to the potentiel for excessive pavement settlement. The subgrade soils exposed following site clearing end stripping must be in a stable, non-yielding condition prior to placement of the pavement section or additional fill . As discussed in the ��NEae! section, a mi�imum of 18 inches of structural fill should be provided above existing topsoil . All pavement sections should be underlain by at least 12 inches of structural fill . In areas of excessively soft existing soils , it may be necessary to IaY a geotextile fabric prior to placing structural fill . If this is necessary, we � GEOTECH CONSULTANTS , INC.