For information into the basic concepts behind an allan block retaining wall design see page 18 of the ab spec book and best.
Block retaining wall design example.
305 mm f m 1 500 psi 10 3 mpa assumed weights.
Based on our example in figure a 1 we have the forces due to soil pressure due to water and surcharge load to consider.
Soil mechanics simplified 4.
There are some great examples of block retaining walls in the photos below from basic cinderblocks to intricate masonry work.
Assume level backfill no surcharge or seismic loading active earth pressure and masonry laid in running bond.
Wall thickness 12 in.
Please note that the gravity wall chart provided has specific heights for specific site and soil conditions.
Soil bearing and stability 8.
Concrete masonry unitsconcrete blocks manufactured to provide an attractive durable stable face to a retaining wall.
Avoid having downspouts pointed at the retaining wall and if it s against the house keep soil and mulch well below the siding.
The interlocking retaining wall block can be used to build walls up to 24 to 36 inches high depending on the size of the block.
It is commonly used to separate drainage material from other soil.
Earthquake seismic design 7.
Sketches of the retaining wall forces should be considered to properly distinguish the different forces acting on our retaining wall as tackled in the previous article retaining wall.
Learn more about gravity wall construction.
Take a look to see if you can make one of these styles work for your project.
The coefficient of friction between the footing and foundation soil k 1 is 0 25 and the allowable soil bearing pressure is 2 000 psf 95 8 kpa ref.
Gravity walls rely on their own weight and setback to hold up the soil behind them.
Retaining wall design 10 editionth a design guide for earth retaining structures contents at a glance.
Follow the block manufacturer s instructions for wall height limits.
If you are not sure of your site conditions we recommend being conservative with your retaining wall heights or use geogrid in your retaining wall.
Design procedure overview 3.
Geotextilea permeable polymeric material which may be woven non woven or knitted.
Design the reinforced concrete masonry cantilever retaining wall shown in figure 2.
The design process for a segmental retaining wall typically has a wall design engineer or site civil engineer responsible for the wall design envelope geotechnical engineers should be hired to evaluate the overall stability of the site.
Retaining walls built from boulders are practical and extremely effective.
Boulder retaining wall ideas.