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j REGG Cone Penetration Testing Procedure <br />(CPT) <br />Gregg Drilling carries out all Cone Penetration Tests (CPT) using an integrated <br />electronic cone system, Figure CPL The soundings were conducted using a 20 ton <br />capacity cone with a tip area of 15 cm2 and a friction sleeve area of 225 cm: The cone <br />is designed with an equal end area friction sleeve and a tip end area ratio of 0.80. <br />The cone takes measurements of cone <br />bearing (qc), sleeve friction (fs) and /-- <br />penetration pore water pressure (le) at 5- <br />cm intervals during penetration to provide B--Soil seal <br />a nearly continuous log. CPT data 4 - - Electric cable for signal transrni,sion <br />. <br />reduction and interpretation is performed - Water seal <br />in real time facilitating on-site decision / <br />making.The above mentioned ,- -Friction load cell <br />parameters are stored on disk for further •-Friction steeve <br />analysis and reference. All CPT <br />soundings are performed in accordance •- - -Inclinometer (1. & ly) <br />with revised (2007) ASTM standards (D u <br />5778-07). <br />The cone also contains a porous filter <br />element located directly behind the cone <br />tip (u). It consists of porous plastic and is <br />5.Omm thick. The filter element is used to <br />obtain penetration pore pressure as the <br />cone is advanced as well as Pore <br />Pressure Dissipation Tests (PPDT's) <br />during appropriate pauses in penetration. <br />It should be noted that prior to <br />penetration, the element is fully saturated <br />with oil under vacuum pressure to ensure <br />accurate and fast dissipation. <br /> - - Tip load cell <br />1 <br />w - Water seal <br />B -- Soil feal <br />LE€Pore pres;ure tfaniducer <br /> Flitef <br />- Corie Tip <br />The cone has the following accuracy: <br />1 tsf for qc, 0.02 tsf for 4 and 0.5 psi for <br />U2· In soft clays, a lower capacity cone <br />should be used for improved accuracy. <br />Figure CPT <br />When the soundings are complete, the test holes are grouted. The grouting procedures <br />generally consist of pushing a hollow tremie pipe with a "knock out" plug to the <br />termination depth of the CPT hole. Grout is then pumped under pressure as the tremie <br />pipe is pulled from the hole. Disruption or further contamination to the site is therefore <br />minimized. <br />SL Rvcd 2019.01.21