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AREGG Cone Penetration Testing Procedure <br />(CPT) <br />Gregg Drilling carries out all Cone Penetration Tests (CPT) using an integrated <br />electronic cone system, Figure CPI 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 cmi 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 (4) and <br />penetration pore water pressure 02) at 5- <br />cm intervals during penetration to provide <br />a nearly contmuous log. CPT data <br />reduction and interpretation is performed <br />in real time facilitating on-site decision <br />making.The above mentioned <br />parameters are stored or, disk for further <br />analysis and reference.An CPT <br />soundings are performed in accordance <br />with revised (2007) ASTM standards (D <br />5778-07). <br />=21 --- <br />1-1-0 -Wial <br />B--- --Eleetcablefoi jignalt,anwnission <br />*lf <br />1 ---hd€fl <br />• - Airld ilene1.1 - &,dh=12,01&41 <br />The cone also contains a porous filter <br />element located directly behind the cone <br />tip (U2)· It consists of porous plastic and is <br />5.Omm thick- The filter element is used to <br />obtain penelration pore pressure as the <br />cone is advanced as well as Pore <br />Pressure Dissipation Tests (PPDT's) .1 <br />during appropriate pauses in penetration.El=U <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 />;Wter leal <br />Wid <br />- Pt,re pressurevansducer <br />'Fiker <br />-cone np <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 />Rgure CPI- <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.