ARCHIVED REPORTS XR0012551 - Laserfiche WebLink

Home Browse Search

ANSI r."d^. ..r .,. a 2.0 FIELD INVESTIGATION 2.1 SITE PREPARATION Proposed CPT investigation locations will be marked. Utility companies will be notified and requested to mark locations of underground utilities. The Earth Technology Project Manager anu a representative of the current site owner will approve final CPT locations before testing is commenced. Geophysical site clearance will be performed as appropriate, based on available site information. 2.2 CONE PENETROMETER ESTI IG The electric cone penetration test(CM will be performed in general accordance with ASTM Standard D 3441-86. The test essentially consists of pushing a cone-tipped cylindrical probe (piezocone) into the ground while simultaneously recording the resulting penetration resistance. The piezocone is attached to the end of a string of steel pipes, each 1.0 meter (3.3 feet) in length, and pushed into the ground at a constant penetration rate of 2 cm/sec (approx. 0.8 in/sec), one pipe length at a time. As the piezocone is pushed deeper, new pipes are attached to the top of the string by means of a tapered thread joint. The pushing force is supplied by heavy hydraulic rants typically mounted inside the rear compartment of a 3-axle truck(Figure 1-A). The weight of the truck(20 tons)p- es the reaction force to push against. The depth of penetration for each location will be 30 feet below ground surface. The CPT rods will be backed out of the hole and th.CPT equipment adapted for BAT"'probe installation. The piezocone contains two strain gauge load cells which measure the soil bearing resistance -- acting on the conical tip and the soil shear resistance sensed along the cylindrical friction sleeve as the probe penetrates the soil. The pore water pressure will be measured by means of a filter and pressure transducer assembly which is built into the probe. A built-in inclinometer will be used to monitor the verticality of the dst. These four measurements w.. 0:w1503A%W9-0121.FL 3