Drilling and Insitu Tests

Conic Penetration Test (CPT,CPTU,SCPT)


The equipment Zemin Etud ve Tasarim A.S. owns and used in the testing is made in Netherlands (original Dutch Cone-A.P.vd Berg). Electronic cone penetration testing (CPT) is a method in which an electronic cone (CPT cone) of 36 mm diameter with a 10 cm² cone area and 150 cm² skin area is pushed into the subsoil with an hydraulic system with a speed of 2 cm/s and thus the cone tip resistance and skin friction values are measured via electronic transducers The obtained data is transferred to computer at the site and the variation of subsoil parameters is determined with depth instantly in graphical form at every 2.0cm. Depth, tip resistance (qc) and side friction (qs) are recorded with depth automatically by the computer. Truck-mounted CPT rig has 20 ton pushing capacity. Tests will be stopped when the machine pushing capacity is attained. CPT tests will be performed according to the ASTM Standards (ASTM D5778-95(2000)). The pictures taken during the Cone Penetration Testing are presented below. To the aim of the survey, CPT equipment provide to obtain different soil parameters and pore pressure with adding additional cones and sensors. A seismic cone can be added in order to determine seismic parameters(Vs and Vp) to the equipment. Using the results of the test, the soil layers can be identified and the geotechnical parameters( effective pressure, undrained shear strength, internal friction angle, relative density, consolidation coefficient, etc.) can be determined. Test methodology is referred by ISSMFE(International Society of Soil Mechanics and Foundation Engineering,1989) and ASTM Standards(ASTM D5778-95(2000)).

+