SU0004714 - Laserfiche WebLink

Home Browse Search

NW, *,we37 If the site is improved by removal and replacement, or by DDC treatment, the site period is expected to be less than 0.45 sec. In this case, the design period should be increased to 0.5 sec per USC recommendations. Liquefaction Potential Soil liquefaction occurs as a result of a loss in shear strength in loose, and medium dense, saturated, cohesionless soils caused primarily by earthquake- induced groundshaking. Liquefaction is considered a hazard at this site if the upper 15-ft of soils, in their existing density condition, are saturated at the time of shaking. Densification of replacement of these soils will mitigate liquefaction effects. Lower deposits are not expected to liquefy owing to the presence of stiff clays and dense sands below the 14-ft depth. Typically, upper medium dense sands with glass will need to be densified or recompacted or replaced to at least the 15-ft depth to provide adequate founda- tion to the proposed structures. This recompaction will provide a mat of com- pacted soil that will help mitigate any liquefaction effects if locally liquefi- able surface soils are saturated at the time of shaking. EARTHWORK AND CONSTRUCTION Earthwork Introduction. To construct the 2-acre "plant" area will require raising the existing ground surface by 2 to 5 ft. As a minimum requirement, all compacted fills, and fill and cut slopes should be constructed in accordance with San Joaquin County regulations for grading and earthwork. Special earthwork considerations are anticipated at this site depending on which foundation option or combination of foundation options are used to develop this site. Site Preparation and Grading. The existing ground surface should be stripped of all organic material, vegetation, and debris. The stripped material should be disposed of off the site. Requirements for additional excavation, or treatment, of the on-site materials is dependent on the foundation option(s) chosen. The exposed surface, after stripping or overexcavation, should be visually inspected by the Soils Engineer, or his representative to evaluate if McClelland 1144A/CC-37 '--