Laserfiche WebLink
CPT Interpretations <br /> lnie—mreted I description Equation Ref <br /> Parameter <br /> E Stress <br /> 6v Effective vertical overburden stress at Mid Layer Depth Estress= Tstress-u., <br /> For hydrostatic option <br /> Equilibrium pore pressure determined from one of the ] <br /> following user selectable options u,=Yw•(D-D I <br /> Ueq where u.,is equilibrium pore pressure <br /> 1) hydrostatic from water table depth 7w is unit weight of water <br /> 2) user supplied profile D is the current depth <br /> D,M is the depth to the water table <br /> Cn SPT N60 overburden correction factor where a,'is in tsf <br /> 05<C„<20 <br /> �- SPT N value at 60%energy calculated from qt/N ratios <br /> Nso assigned to each SBT zone This method has abrupt N See Figure 1 4 5 <br /> value changes at zone boundaries <br /> - SPTN Value at 60%energy This method is a slight — <br /> modification of the Jefferies and Davies technique <br /> N80(Ic) whereby the qt/N ratio varies across sod classification See Figure 1 5,8 <br /> zones based on the Ic parameter This techniques is <br /> limited to zones 2 through 7 on the normalized Soil <br /> Behavior Type Chart <br /> A)w SPT NN value corrected for overburden pressure (Nino=Cn •Nso -I-^ 4 - <br /> AM)"= l KK •W.). <br /> sPr <br /> Where KsPT is defined as , <br /> a(N,)w Equivalent Clean Sand Correction to(Ni)Bo 0 0 for FC a 5% a <br /> 0 0167•(FC-5) for 5%<FC<35% <br /> 05 for FC a 35% <br /> FC-Fines Content in% <br /> -�(IVi)eo.s - Equivalent Clean Sand(Ni)Bo (N1)eo.-(N1)eo + 4(N1)eQ 4 <br /> -I -- -- -- - - -- - <br /> - <br /> Su Undrained shear strength-Nig is user selectable Su=q1—w 1, 5 <br /> k Coefficient of permeability(assigned to each SBT zone) _ 5Au - <br /> Bq= <br /> qr-U, <br /> Bq Pore pressure parameter where Du=u-u,q 1 5 <br /> _ - and u=dynamic pore pressure -- <br /> u.=equilibrium pore pressure <br /> -- Normalized qt for Soil Behavior Type classification as )r=qr � - 2,5 <br /> Qi defined by Robertson, 1990 <br /> -� Normalized Friction Ratio for Soil Behavior Type Fr=100%0 fs -�rv_� -�------- 2, 5 <br /> F, classification as defined by Robertson, 1990 q1-6� - — <br /> _ SBTn - Normalized Soil Behavior Type as defined by Robertson See Figure 2 2 5 <br /> and Campanella <br /> REGG <br /> CPTSUMM-1 20C-Rev 02-07-31 <br />