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.