Best Practices for Zero Retaining Wall Failures - Wall Embedment with Toe Slope

Whenever walls are constructed in a terraced arrangement the designer should consider the overall global stability of the structure.

It is common to have the design grid lengths for the bottom terrace equal to at least 60% of the total terraced structure height.

Subsequent terraces above would use similar rationale to determine their minimum grid lengths.

Greater attention to compaction should be placed on the foundation soils below the upper terraces and in transition areas where the wall splits from one wall into two.  If the soils are not properly compacted in these areas, settlement can occur over time that could cause aesthetic concerns.  (ref. BP, Chapter 10.1)

Allan Block is working to achieve our industry initiative of Zero Wall Failures. With our Best Practices Manual and experience in the industry we are trying to expand the knowledge base for the design of segmental retaining walls (SRW's) by communicating and educating the professionals in the industry.  To see the full Best Practices Manual, visit allanblock.com to download today and keep an eye out for more industry Best Practice recommendations here.

Best Practices for Zero Retaining Wall Failures - Effect of Groundwater on Global Stability

In water applications such as retaining walls bordering detention ponds, global stability of the SRW system should often be analyzed.  This is to assure that the adequate factor of safety exists for deep failures that pass behind the geosynthetic reinforcement and for compound failures that pass partially through the reinforced soil mass and partially behind the reinforced soil mass. 

Whenever the groundwater is within two-thirds of the height of the wall below the bottom of the wall, this analysis should be run.  If the cause for the global stability problems is weak foundations soils, it may be necessary for the geotechnical engineer on the project to do foundation improvements before the retaining walls are built.(ref. BP, Chapter 9.4)

Allan Block is working to achieve our industry initiative of Zero Wall Failures. With our Best Practices Manual and experience in the industry we are trying to expand the knowledge base for the design of segmental retaining walls (SRW's) by communicating and educating the professionals in the industry.  To see the full Best Practices Manual, visit allanblock.com to download today and keep an eye out for more industry Best Practice recommendations here.

Best Practices for Zero Retaining Wall Failures - Increasing Global Stability Options

If your retaining wall has global stability concerns, there are several things you can try to improve the stability:

• Increasing the length of the geogrid layers to force the minimum slip arcs deeper into the hillside.
• Increasing the depth of buried block to force the minimum slip arcs deeper into the hillside.
• Increasing the strength of the geosynthetic reinforcement layers to force the minimum slip arcs deeper into the hillside.
• Increasing the friction angle of the infill soil will increase the soil’s shear resistance which will increase stability. (ref. BP, Chapter 9.3)

Allan Block is working to achieve our industry initiative of Zero Wall Failures. With our Best Practices Manual and experience in the industry we are trying to expand the knowledge base for the design of segmental retaining walls (SRW's) by communicating and educating the professionals in the industry.  To see the full Best Practices Manual, visit allanblock.com to download today and keep an eye out for more industry Best Practice recommendations here.