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10.2.4 Symbols.

9-4 Site plan.

For every investigation which is carried out, a elear site plan shall be drawn, with elear reference points in order that the locations of the penetrometer tests are accurately plotted.

Also when madę in conjunction with borings the time seąuences are to be indicated of the performance of the borings and CPT tests.

Tests performed with a diverging cone cannot be represented by the letter S, as they dif-fer from the Standard. If all other elements are identical as in the Standard, they can be indicated by the letters M, E, H, but followed by the indication B = and a = giving the values of the diverging charac-teristics of the cone.

9.5 Besides the information mentioned under para. 9*1, it is recommended that the elevation of the soil-surface at the lo-cation of the test is given. In addition, where appropriate the following information should be given:

(a)    The readings of the inclinometer, if taken.

(b)    Ali checks madę after extracting the push-rods, the conditions of the push-rods and the penetrometer tips.

(c)    The depth of the water in the hole re-maining after withdrawal of the penetrometer, or the depth at which the hole collapsed.

(d)    Whether or not the testhole has been backfilled, and if so by which method.

10. DIVERGENCES FROM THE STANDARD RECOMMENDED

10.1 General.

A generał and very important specification is, that all divergences from the Recommended Standard are to be described ex-plicitly and completely on the test graphs. In order to simplify these remarks the names or symbols defined in para. 10.5 can be used.

10.2 Divergences only related to the dimen-sions and the shape of the cone.

10.2.1    Diameter of the base of the cone.

In order to be able to penetrate deeper in certain cases a cone with a smaller base can be used. In order to be able to include the measuring device, or to be able to drive the penetrometer tip through hard layers with less danger of damage occurring to the tip, cones with larger diameters are used.

10.2.2    Apex angle of the cone.

To decrease the possibility of damage, an apex angle of 90 can be used.

10.2.3    Tolerances.

All tolerances specified for the Recommended Standard, are to be adapted in direct proportion to the diameter.

10.3 Divergences only related to the lo-cation or dimensions of the friction sleeve.

10.3.1    If the friction sleeve, contrarily to the Recommended Standard, is not placed immediately above the base of the cone, the minimum distance (h) between that base, and the lower end of the friction sleeve should be three times the diameter of the base.

10.3.2    Surface of the sleeve.

When using a cone having a base diameter of 35.7 mm, but with a friction sleeve of a length other than the Recommended Standard, then the surface area of the sleeve should not be larger than 350 cm², and not smaller than 100 cm².

When using a cone with a base diameter dif-ferent from the Recommended Standard, the surface area of the sleeve should be adjusted proportionally to the surface area of the base of the cone.

10.3.3    Symbols.

Tests performed with a diverging friction sleeve cannot be represented by the letter S, as they differ from the Recommended Standard. If all other elements are identical as in the Recommended Standard, they can be indicated by the letters M, E, H, but followed by the indication:

height of lower end of sleeve h = surface area of the sleeve A_s =

10.4 Discontinuous testing with freee cone penetrometer tips.

10.4.1    With a free cone penetrometer tip, either continuous or discontinuous testing is possible. The manner in which the test is performed should be described in the report and on the test graphs.

10.4.2    Discontinuous testing.

In the case of discontinuous testing, although the ratę of downward movement due to the thrust machinę is known, the ratę of pen-etration of the free cone at the point of rupture of the soil can be different to that of the movement due to the thrust machinę. They only correspond when there is continuous downward movement of the push-rods.

When testing discontinuously the minimum

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