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TABLE l: ALLOWABLE LATERAL LOAD CAPACITY OF CAISSONS <br />Deflection (inch) <br />Allowable Lateral Load (Tons) <br />3.5-Foot Diameter <br />4-Foot Diameter <br />1/4 <br />10 <br />15 <br />1/2 <br />25 <br />30 <br />1 <br />50 <br />60 <br />The lateral capacity indicated above refers to the resistance available on the side of the <br />caisson. Additional resistance to lateral lads will be provided by passive soft pressure against the <br />caisson cap. Anumlop and and gravel or {lacial till beckfift is placed adjacent to the caisson cap <br />and compacted at or near optimum moisture content to 95 percent of the maximum dry density <br />in accordant with ASTht D-1557 test procedures, the lean! sell preanre against the cap may <br />be approximated by assuming an equivalent fluid density of 350 pounds per cubic foot (pcf). If <br />ban concrete is placed adjacent to the cap. the lateral earth pressure may be approximated using <br />an equivalent density of 400 pcf. These values include a factor of safety of 1.5 and are consistent <br />with a lateral deflection of 0.5 inches. In addition, lateral seismic lads may be resisted with the <br />equivalent fluid densities presented heroin. To develop the recommended equivalent fluid <br />pressure, the compacted backfill or loan concrete should extend horizontally a distance equal to <br />three times the embedment depth of the cap. <br />5.2.3 U192m2pI <br />Total settlement for individual caissons will be proportional the diameter of the caisson. We <br />estimate that the caissons will experience about 1/4 and 1/2 inch settlements for diameters of 4 <br />and S feet, respectively. Differential settlement between adjacent columns in the proposed <br />expansion is estimated at 1/4 inch or less. Theme settlements are expected to be elastic in nature <br />and will occur essentially simultaneously with the application of lad. <br />s-005-006t4.016%ssosOr00.mp <br />00695-SM-016 10 <br />