Laserfiche WebLink
lite: J1 dUU2 11 : 108M GREGG DRILLING 52531303022"GG <br /> EGG p. l <br /> EGG IN SI 1 Uq INC. <br /> �® Geotechnical and Environmental In Situ Testing Contractors <br /> CONE P ENETR,ATION TESTING (CPT) <br /> Gregg In-Situ's Cone Penetrometer Tests(CPT)are <br /> carried out using an integrated electronic piezopona. <br /> The piezocone,is pushed using a specially designed CPT <br /> i <br /> rig.With a farce capacity of 20 to 25 tons. <br /> A compression type cone is used for each CPT sound- <br /> ing. PieZo=es with rated load capacities of 5,10 or 20 <br /> tons are used depending on soli conditions. The 5 and ` <br /> 10 ton cones have a tip area of 10 sq cm and a frict ion <br /> sleeve area of 150 sq cm. The 20 ton carnes have a tip <br /> fir:rF area of 15 sq cm and a friction sleeve area of 225 set cm. <br /> ,� A pore water pressure transducer is located directly be- <br /> i''€; hind the cone tip. Each filter is saturated in glycerin urr <br /> der vacuum pressure prior to each CPT sounding, Pore <br /> .r Pressure Dissipation Tests(PPDT)are recorded at 5 <br /> Triaxial Geophones second intervals during pauses in penetration. The equi- <br /> 0[Accelerrztteter libriurn pore water pressure from the dissipation last can <br /> (Vp} �)•� = be used to identity the depth to groundwater. <br /> The piezocones.arecapable of recording the following <br /> parameters at 2.5 a6d 5 cm increments; <br /> Tip Resistance(qc) <br /> r.� Sleeve Friction(ft) <br /> t Inclinometer Q) -D)mamic Pore Pressure(U) <br /> -Resistivity (rho)Alth added module <br /> TfienniStDr(T) -Ultra Violet Induced Fluorescence(UVIF) <br /> The measured parameters are-printed simultaneously an. <br /> ` x a prtnter and stored on a computer disk In ASCEII format <br /> - Friction Sleeve(Fs) For future analysis. All CPT's are carried out in accor- <br /> dance with ASTM D-5778-95, A complete set of trase- <br /> .r Load Cells tines readings are takers prior to each sounding to deter- <br /> mine any aero load offsets. <br /> Y; The inferred stratigraphic profile of each CPT location is <br /> ' included on each CPT plot. The stratigraphic interpreta- <br /> `� Pore Pmswm tions are biased on relationships between cone bearing <br /> Porous Fitter ' ' Transducer(U) (qc)and friction natio(Rf). The friction ratio is a calcu-. <br /> Element lated parameter(t/qc) used in conjunction with the cone <br /> Con9lip(QC) bearing to identifysoil behaviortype, Generally,soft <br /> cohesive soils have low cone bearing and high friction <br /> ratios. Cohesionless soils(sands)have a high cone <br /> bearing and low friction ratios. The classification of soils <br /> is based on corre lations developed by Robertson st at <br /> (1988). It Is not always possible to clearly identify a soil <br /> type based an qt:and Rf alone. Correlation with existing <br /> soils Information and analysis of pore pressure measure- <br /> ments should also be used in determining soil type. <br /> Los Angeles(corporate)-San Francisco -Houston •Chariston <br /> Vancouver--Salt Lake City•New Jersey <br /> Tel:(562)427-6899-Fax(562)424-2329-Website:www.greggdritiina.com <br /> I lip <br /> v <br /> .r <br />