Maximum wall heights (in block height, metres, feet) for a single skin, mass gravity,
block retaining wall system - without additional interlocking keys, reinforcements
or backfill stabilizing.
Wall height
measured from top of foundation / levelling pad.
Top of foundation
/ levelling pad a minimum of 150mm / 0.5 ft below ground level
No allowance
made for surcharge above wall
Angle of internal
friction used in calculations: P(firm clay)>26°,P(silty sand)>32°.
Compaction effort
at optimum moisture content to ensure maximum density achievable.
Provided that
groundwater conditions are controlled, a wide variety of soil types can be
used for infill soil.
Subsoil drainage
is essential to intercept groundwater. Build-up of hydrostatic pressure and
seepage forces minimised.
Surface water
run-off should be directed away from the wall
