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OEMgg 001 55NN ig .a-gmg M. "IMU f�"' .aR ift "I ' T • �1 S .� .� �iC`9C.1YwMwTLS4i.'b[?gR.1!s@LIS PILAN4r�l�iS�^-•Z SkO.�fOca.HMS cnn:.M:YV6M1.G: i 00 will be recGrded continuously as a function of depth, and transmitted as . slog voltage signals through a cLble inside the push pipes to an electronic data acqui..,ton systein located inside the cone penetrometer rig. The on-board data acquisition system converts the analog signals received from the piezocone into digital data, and stores the data at small depth increments (typically about 1 inch) on a personal computer system also mounted inside the truck. This data can be displayed on a monitor while the test is proceeding, and can be printed or plotted upon completion of the test to provide an automatic log of penetration. The data log typically consists of the measured cone tip resistance (qc), friction sleeve resistance (fs), and pore water pressure (u), on as well as two calculated parameters, the friction ratio (defined as the ratio of sleeve iric by y to tip resistance, or fslgc) and the pore pressure ratio (essentially pore pressure divided tip resistance, or ulgc). Interpretation of the CPT data is necessary to derive the strttigraph:c and hydrogeologic site information. The stratigraphy is derived from the c;s� ,tip-Trsistance (qc) and friction ratio w (sslgc)parameters. The qc values are normalized to nedsalize the effects of overburden rough numerous side-by-side CPT and borehole pressure. This chart was developed th sample laboratory analysis correlations, and has been digitized and ince-,porated into a computer program which resides in the on-board PC. On-site predictions of soil € gene a classification can therefore be printed out as a funetirm of depth, essentially g g detailed "boring log" witlivit actually seeing the soil. depth to groundwater, aquifer connectivity, and Hydrogeologic information, such as permeability(hydraulic conductivity) is derived from the piezocone pore pressure measurements (u). Essentially, any moisture bearing zone is identified by a positive pore �. pressure measurement. The measurxl pore pressure'in clays tends to be higher than that in sands because the lower permeability of clays tends to prevent rapid dissipation of the "excess" pore pressure. Excess pore pressure is generated from the disturbance caused by the advancing probe. Therefore, to define the piezometric level of an aquifer, the hydrostatic 4 0;w9M a OIN9-01v.n. FF �r a•�'RAl�fklY06�.��®�1�1�111��r1�1fJi IR"Itl101ilM/�