2016-03-01 Planning & Organisation Committee Agenda

Page 28 of 79

Sampling Methods

The results of the SPT tests can be related
empirically to the engineering properties of the
soils.

Dynamic Cone Penetrometer Tests /
Perth Sand Penetrometer Tests
Dynamic penetrometer tests (DCP or PSP) are
carried out by driving a steel rod into the ground
using a standard weight of hammer falling a
specified distance. As the rod penetrates the soil
the number of blows required to penetrate each
successive 150 mm depth are recorded. Normally
there is a depth limitation of 1.2 m, but this may be
extended in certain conditions by the use of
extension rods.  Two types of penetrometer are
commonly used.
e   Perth sand penetrometer - a 16 mm diameter
    flat ended rod is driven using a 9 kg hammer
    dropping 600 mm (AS 1289, Test 6.3.3). This
    test was developed for testing the density of
    sands and is mainly used in granular soils and
    filling.
e   Cone penetrometer - a 16 mm diameter rod
    with a 20 mm diameter cone end is driven
    using a 9 kg hammer dropping 510 mm (AS
    1289, Test 6.3.2).  This test was developed
    initially for pavement subgrade investigations,
    and correlations of the test results with
    California Bearing Ratio have been published
    by various road authorities.

                                                                                              July 2010

                                                                                               Page 28 of 79