2824 GRAND AVE NAUTICA CONDOMINIUMS 2018-01-02 MF Import

GEOTECHNICAL ENGINEERING STUDY Cascasia Pacific Properties, Ltd. July 15, 1999 E-8602 Page 6 1 he ground surface where foundations, or structural fill are to be placed should be observed by a representative of ECI. Loose or unstable subgrade soils should be compacted or replaced with structural fill. The use of lean mix concrete can also be considered in lieu of structural fill for use in replacing overexcavations in foundation areas. Some of the native soils are moisture sensitive, and will become unstable when exposed to excessive moisture. The poorly graded sand with silt encountered throughout much of the site has only moderate moisture sensitivity. Compaction and grading of the native soils, however, will be difficult if the moisture content of the soil is above optimum. As previously mentioned in the "Subsurface" section of the report, brick and concrete rubble was encountered to a depth of approximately three feet at test pit location TP-2. These fill soils should not be used as structural fill. During dry weather, the native soils can be considered for use as structural fill, provided the moisture Conte it of the soil is at or near optimum at the time of placement. At the time of our exploration, the majority of the native soils above a depth of approximately ten (10) feet had moisture contents that were at or near tY - optimum moisture content. If imported soil is necessary for use during wet weather conditions, the fill should consist of a fairly well graded granular material having a maximum size of three inches and no more than five percent fines passing the No. 200 sieve based on the minus 3/4-inch fraction. Structural fill is defined as compacted fill placed under foundations, roadways, slabs, pavements, or other load -bearing areas. Structural fill under slabs and footings should be placed in horizontal lifts not exceeding twelve (12) inches in loose thickness and compacted to a minimum of 90 percent of its laboratory maximum dry density. The maximum dry density should be determined in accordance with ASTM Test Designation D-1557 (Modified Proctor). The fill materials should be placed at or near the optimum moisture content. Fill under pavements and walks should also be placed in horizontal lifts and compacted to 90 percent of maximum density except for the top twelve (12) inches which should be compacted to 95 percent of maximum density. E.Rh co ... k.ml, 1, .