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DEPTH OF <br />LOCATION <br />C-13 <br />C-13A <br />C-14 <br />CPT(ft)COMMENTS/NOTES: <br />3 Refusal, hole caved @ 3.0 ft (dry) <br />65 Groundwater @ 16.0 ft <br />65 Groundwater @ 14.5 ft <br />TABLE 2.1 - Summary of CPT Soundings <br />3. FIELD EQUIPMENT & PROCEDURES <br />The CPT soundings were carried out by KTE using an integrated electronic cone system <br />manufactured by Vertek. The CPT soundings were performed in accordance with ASTM <br />standards (D5778). The cone penetrometers were pushed using a 30-ton CPT rig & a direct <br />push rig anchored with 3/4-inch concrete anchors. This rig has a pushing capacity of <br />approximately 15 tons. The cones used during the program were a10 cmA2 &15 cmA2 cone <br />and recorded the following parameters at approximately 2.5 cm depth intervals: <br />• Cone Resistance (qc) •Inclination <br />• Sleeve Friction (fs) •Penetration Speed <br />• Dynamic Pore Pressure (u) <br />At locations C-11 & C-12A, shear wave measurements were obtained at various depths. The <br />shear wave is generated using an air-actuated hammer, which is located inside the front jack <br />of the CPT rig. The cone has a triaxial geophone, which recorded the shear wave signal <br />generated by the air hammer. <br />The above parameters were recorded and viewed in real time using a laptop computer. Data <br />is stored at the KTE office for future analysis and reference. A complete set of baseline <br />readings was taken prior to each sounding to determine temperature shifts and any zero load <br />offsets. Monitoring base line readings ensures that the cone electronics are operating <br />properly. <br />4. CONE PENETRATION TEST DATA & INTERPRETATION <br />The Cone Penetration Test data is presented in graphical form in the attached Appendix. <br />These plots were generated using the CPeT-IT program. Penetration depths are referenced to <br />ground surface. The soil classification on the CPT plots is derived from the attached CPT <br />Classification Chart (Robertson) and presents major soil lithologic changes. The stratigraphic <br />interpretation is based on relationships between cone resistance (qc), sleeve friction (fs), and <br />penetration pore pressure (u). The friction ratio (Rf), which is sleeve friction divided by cone <br />resistance, is a calculated parameter that is used along with cone resistance to infer soil <br />behavior type. Generally, cohesive soils (clays) have high friction ratios, low cone resistance <br />and generate excess pore water pressures. Cohesionless soils (sands) have lower friction <br />ratios, high cone bearing and generate little (or negative) excess pore water pressures. <br />Tables of basic CPT output from the interpretation program CPeT-IT are provided for CPT data <br />averaged over one foot intervals in the Appendix. Spreadsheet files of the averaged basic <br />CPT output and averaged estimated geotechnical parameters are also included for use in <br />further geotechnical analysis. We recommend a geotechnical engineer review the assumed