RFI -Attachment 6 - Geotechnical Investigation Report CORE.pdf

Walsh Consulting Engineers


Table of Contents
1.0       INTRODUCTION .................................................................................................................................... 1
2.0       PROPOSED DEVELOPMENT ............................................................................................................... 1
3.0       SITE DESCRIPTION .............................................................................................................................. 2
4.0       SCOPE AND METHOD OF INVESTIGATION ....................................................................................... 3
4.1       Review of Available Geological Mapping ............................................................................................... 4
4.2       Fieldwork................................................................................................................................................. 4
4.3       Geotechnical Laboratory Testing ............................................................................................................ 4
5.0       INVESTIGATION FINDINGS .................................................................................................................. 5
5.1       Published Geological Information ........................................................................................................... 5
5.2       Ground Conditions .................................................................................................................................. 6
6.0       GEOTECHNICAL COMMENTS & RECOMMENDATIONS ................................................................... 6
6.1       Earthworks .............................................................................................................................................. 6
6.1.1         Site Preparation .................................................................................................................................. 6
6.1.2         Trafficability & Working Platforms ....................................................................................................... 6
6.1.3         Excavations......................................................................................................................................... 6
6.1.4         Filling................................................................................................................................................... 6
6.1.5         Batter Slopes ...................................................................................................................................... 7
6.2       Foundation Design and Parameters ....................................................................................................... 7
6.2.1         Site Classification ............................................................................................................................... 7
6.2.1         High-level Footings ............................................................................................................................. 7
6.2.2         General Comments on Footings ......................................................................................................... 8
6.3       Retaining Wall Design and Parameters .................................................................................................. 8
6.4       Soil Dispersion & Erosion Protection ...................................................................................................... 8
6.5       Drainage ................................................................................................................................................. 9
6.6       Aggressivity of soils ................................................................................................................................ 9
7.0       ASSESSMENT OF LAND STABILITY ................................................................................................... 9
7.1       Existing Condition ................................................................................................................................... 9
7.2       Stability Risk Assessment..................................................................................................................... 10
8.0       SUMMARY AND CONCLUSIONS ....................................................................................................... 11
9.0       LIMITATIONS ....................................................................................................................................... 11




Tables
Table 1: Summary of geotechnical classification testing. .................................................................................. 5
Table 2: Summary of soil aggressivity testing. .................................................................................................. 5
Table 3: Retaining structure design parameters. .............................................................................................. 8
Table 4: Soil aggressivity exposure classifications. .......................................................................................... 9
Table 5: Stability risk levels. ............................................................................................................................ 10
Table 6: Qualitative risk assessment for property (based on AGS 2007) ....................................................... 11




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