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02/19/2003 10 54 843-832-4919 GREGG SUMMERVILLE PAGE 02 _ <br /> 17 <br /> Applieauons Guide-Cl'T' <br /> Geotechnical parameters <br /> Hydraulic conductivity (k) <br /> ' An approximate estimate Of soil hydraulic recompression and can be determined from <br /> conductivity or coefficient Of permeability, k, laboratory consolidation tests Baligh and <br /> can be made fonts an estimate of soil Levadoux recommended that RR should <br /> ' behaviour type using the CPT classification !range from 0 5x10'2 to 2x1.072 t <br /> Charts Table 4 provides estimates based on Table 5.Estimation of soil permeability(k)from <br /> the nan-norrnalized chart shown in Figure 2 the normalized CPT soil behaviour chart by <br /> (Robertson et al , 1986), while Table 5 Robertson(1990) shown in Figure 3. <br /> provides estimates based on the normalized <br /> Zone Soil Behsviour'Iype Range of <br /> chart shown in Figure 3 (Robertson, 1990) (SBT) permeability <br /> ' These estimates are approximate at best, but km/s <br /> can provide a guide to variations of possible <br /> permeability 1 Sensitive tine grained 3x10"p to 3x108 <br /> 2 Organic soils IxiO'to 1x10 <br /> Table 4, Estimation of soil permeability(k) frons 3 Clay 1x10"1°to 1x10-9 <br /> the non-normalized C?T soil behaviour chart by 4 Slit mixtures 3x10"to 1x10'' <br /> Robert"n et RL(1986)shown im Figure 2_ 5 Sand immiures 1x10'to 140-3 <br /> 6 Sands 1xI0 s to 1xI0'' <br /> Zone Soi[Behaviour Type Range of <br /> 7 Gravelly sands to dense 1x10- to I <br /> (SBT) permeability <br /> k m/s sands <br /> 1 Sensiuve fine grained 3x10 to 3x10'] 8 Very stiff sated to clayey 1x10 to ix10' <br /> sand <br /> 2 organic soils 1x10 to Ix10' <br /> 9 Very st <br /> 3 Clay 1x10"10 to Ix10A t#'fine-grai><ied 1x10'9 to ix10'' i <br />' soil <br /> 4 Silty clay to clay 1x10-9 to 1x10'6 <br /> 5 Clayey sdt to silry clay 1x104 to IX10-7 10-11 <br /> 6 Sandy silt to clayey silt 1x101 to 1x10' <br />' 7 Silty sand to sandy silt 1x10 3 to 1x10' <br /> 8 Sand to silty sand 1X10.3 to 1x101 10_5 <br /> 9 Sand 1x10-4 to 1x104 z <br /> 10 Gravelly sand to dense 1x10 to I <br />' sand 10-' <br /> 11 Very still fine-grained 1x10"9 to 1x10'' • • ; <br /> soil <br /> 12 Very stiff sand to clayey 3x].0'to 3x10' _ 10-' <br /> sand % <br /> • 3chmarnnannfts��j <br /> Baligh and Levadoux (1980) recommended <br /> that the horizontal coefficient of permeabdity <br /> can be estimated f&om the expression 14'' <br /> e z 4 <br />' kh - Y RR ch <br /> 01 1 l fl 1 d0 1000 10 000 <br /> t,.(min) <br />' where RR is the re-compression .ratio in the Figure 7. Summary of data for estimating <br /> overconsolidated range It represents the horizontal coefficient of pe»neability from <br />' strain per log cycle of effective stress during dissipation tests(after Robertson et al_,1992)_ <br />' P K Itobertsank u"L�k Lit Lj-'tax' use- 1 K rr� 1- 1998 r <br />