Slope Stability Report

          PRACTICE NOTE GUIDELINES FOR LANDSLIDE RISK MANAGEMENT 2007




    114                      Australian Geomechanics Vol 42 No 1 March 2007

Form No. 68029 RL2 August 2010


[OCR of page images]
PRACTICE NOTE GUIDELINES FOR LANDSLIDE RISK MANAGEMENT 2007

    
  
 
 
  
  
  
 
 
 
  
 

EXAMPLES OF GOOD HILLSIDE PRACTICE

Vegetation retained

Surface water interception drainage —

Watertight, adequately sited and founded
roof water storage tanks (with due regard for
impact of potential leakage)

Flexible structure ———— \
Roof water piped off site or stored

On-site detention tanks, watertight and
adequately founded. Potential leakage
managed by sub-soil drains “>

\. MANTLE OF SOIL AND ROCK
FRAGMENTS (COLLUVIUM)

 
 
 
 
 
 

Vegetation retained \

\ *—Pier footings into rock
‘— Subsoil drainage may be

\ required in slope
Cutting and filling minimised in development

\
= Sewage effluent pumped out or connected to sewer.
Tanks adequately founded and watertight. Potential
leakage managed by sub-soil drains

     
   

“\— Engineered retaining walls with both surface and
subsurface drainage (constructed before dwelling) @ acs (2006)

EXAMPLES OF POOR HILLSIDE PRACTICE

Unstabilised rock topples
and travels downslope

 

+

    
   
 
  
 
  
 
 
 
 
  
  
 
 
   
 
  
  
  

Vegetation removed ——,

Discharges of roofwater soak Steep ening
away rather than conducted off cut fails
site or to secure storage for re-use ———.

 

Structure unable to tolerate
settlement and cracks

Poorly compacted fill settles
unevenly and cracks pool SX

Inadequate walling unable
to support fill

Loose, saturated fill slides
and possibly flows downslope
Inadequately supported cut fails —, Roofwater introduced into slope

Saturated \
slope fails —
Vegetation Dwelling not founded in bedrock
removed —

il?
Absence of subsoil drainage within fill
Ponded water enters slope and activates landslide (©) AGS (2006)
Pia travel downslope which impacts other development downhill See also AGS. (2000) Appendix J

 

Australian Geomechanics Vol 42 No 1 March 2007

Form No. 68029 RL2 August 2010