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on the drift of the push-rods into the soil, inclinometers may be built into the pen-etrometer tip.

The need of such information depends on the soil conditions and increases with increas-ing depth of the test.

8.3 Push rods with smaller diameters.

In order to decrease the skin friction on the rods, use can be madę of push-rods with a smaller diameter than that of the pen-etrometer tip. The distance between the smaller diameter push-rods and the cone base should be at least 1000 mm.

9. REPORTING OF RESULTS

9.1 The following information shall be

reported on the graphs of the measurements:

1.    In order to State that the penetrometer and the test procedurę are completely in agreement with the recommended Standard, each graph shall be marked with the letter S.

After this letter will be added one of the following letters indicating the system of measurement:

M = mechanical E = electric H = hydraulic

2.    The datę of the test and the name of the firm.

3.    The identification number of the CPT test and the location of the site.

4.    The depth from which a friction reducer, or push-rods with a reduced diameter, have been used. The depth at which the push-rods have been extracted over a limited height in order to break the lateral resistance, after which the push-rods have again been pushed into the soil.

5.    Any abnormal interruption from the normal procedurę of the CPT test.

6.    Observations madę by the operator such as soil type, sounds from the extension rods, indications of stones, disturbances, etc.

7- Data concerning the existence and thick-ness of fili, or existence and depth of an excavation, and level of the CPT test with respect to the original or arti-ficial soil surface.

9.2 Besides the information indicated in para. 9*1, the internal files should also mention:

1.    The Identification number of the penetrometer tip used.

2.    The name of the operator in charge of the crew which performed the test.

3. The dates and reference numbers of the calibration certificates for the measure-ing devices.

9.3 The following scales are recommended for the presentation of the graphs:

Depth scalę: 1 unit length (arbitrary) for

1    m

Cone resistance q_c: the same unit length for

2    MPa

Local side friction f_s: the same unit length for 0.5 MPa

Total penetration force Q_t: the same unit length for 5 kN

Total friction Q_st:    ditto

So long as the above mentioned relationships between the scales along the vertical and horizontal axis are respected, the scales can be chosen arbitrarily in such a way that standard sized sheets can be used.

Fig. 4 An example of the presentation of test results from a CPT test.

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