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{{OR/14/052}}
==Lightweight dynamic cone penetrometer==
The undrained shear strength (Cu) of the soils was investigated by performing in situ strength tests using a variable energy dynamic penetrometer, Panda2 lightweight penetrometer.

The Panda2 dynamic cone penetrometer measures the ''in situ ''dynamic cone resistance (in MPa) of the soil through which it is passing and can be used for indirect estimation of in situ relative density and undrained shear strength (Cu) and for stratigraphic mapping of soils in the shallow subsurface. The test is undertaken by driving a 4 cm2 sacrificial steel cone on the end of a set of 0.5 m long threaded steel rods using a fixed weight (hand held) hammer through the target deposit. The Panda2 measures the velocity of the hammer impact on the head of the rods and the depth of cone penetration in order to determine the dynamic cone resistance (qd) using a modified form of the Dutch Formula (Langton, 1999)<ref name="Langton 1999">Langton, D D. 1999. The Panda lightweight penetrometer for soil investigation and monitoring material compaction. ''Ground Engineering'', p.33–37.</ref>. The Panda2 is capable of reaching depths of up to 6 m in soils with a resistance up to 20 MPa. It is relatively lightweight (20 kg) and readily portable thereby making it ideal for testing soils ''in situ'', particularly where access is restricted, such as on coastal, river, landslide scarp and quarry exposures.

A more detailed explanation of the Panda Penetrometer testing methodology and correlations with other dynamic and static cone penetration tests can be found in Langton (1999)<ref name="Langton 1999"></ref> and Amor et al (1999)<ref name="Amor 1999">Amor, S J, Burtwell, M H, and Turner, A S. 1999. Panda dynamic cone penetrometer assessment. ''Transport Research Laboratory'', Crowthorne.</ref>. One limitation of the technique in coarse-gravel and cobble/boulder rich tills is that the cone can become obstructed by coarse grained stronger particles (cobbles & boulders) and this can limit penetration depth, and effect interpretation of results.

===Details of in situ strength testing (Panda2 soundings)===
Full raw Panda2 data and cone resistance plots are proved in Appendix 2.

<center>
{| class="wikitable"
|+ Table 3    Details of Panda penetrometer testing
|- style="vertical-align:top;"
| style="background-color: #dcdcdc;" | '''Site Name'''
| style="background-color: #dcdcdc;" | '''Profile name'''
| style="background-color: #dcdcdc;" | '''Termination Depth (m)'''
| style="background-color: #dcdcdc;" | '''Unit'''
| style="background-color: #dcdcdc;" | '''Orientation'''
|- style="vertical-align:top;"
| ! scope="col" style="width: 100px;" rowspan="7" | Cemlyn Bay
| ! scope="col" style="width: 100px;" | P001
| ! scope="col" style="width: 85px;" | 0.109
| ! scope="col" style="width: 200px;" | Sand lens — NB Invalid test due to brittle soil fracture
| ! scope="col" style="width: 150px;" | Vertical
|- style="vertical-align:top;"
| P002
| 0.122
| Sand lens
| Vertical
|- style="vertical-align:top;"
| P003
| 0.292
| Sand lens
| Horizontal
|- style="vertical-align:top;"
| P004
| 0.234
| Sand lens
| Vertical
|- style="vertical-align:top;"
| P005
| 0.049
| Grey till
| Vertical
|- style="vertical-align:top;"
| P006
| 0.330
| Sand lens, grey till at base
| Vertical
|- style="vertical-align:top;"
| P007
| 0.333
| Grey till
| Vertical
|- style="vertical-align:top;"
| rowspan="5" | Beaumaris
| P008
| 0.592
| Grey till
| Vertical
|- style="vertical-align:top;"
| P009
| 1.306
| Grey till
| Vertical Start height 5 cm lower than P008
|- style="vertical-align:top;"
| P010
| 0.299
| Red till
| Vertical
|- style="vertical-align:top;"
| P011
| 0.321
| Red till
| Vertical
|- style="vertical-align:top;"
| P012
| 0.204
| Red till
| Vertical
|- style="vertical-align:top;"
| rowspan="2" | Port Nobla
| P014
| 0.294
| Red till
| Vertical
|- style="vertical-align:top;"
| P015
| 0.479
| Red till
| Vertical
|}
</center>
==References==
<References/>
[[Category:OR/14/052 Physical properties of till deposits from Anglesey, north west Wales | 07]]

OR/14/052 Field tests - Revision history

Dbk: 1 revision imported

Ajhil at 10:05, 26 February 2016