This data base of 171 failed mechanically stabilized earth (MSE) walls with geosynthetic reinforcement includes 44 cases of excessive deformation and 127 cases of collapse of at least part of the wall. The large majority are located in North America and in the USA in particular. The main statistical findings are as follows:
96 % were private (as opposed to public) financed walls
78 % were located in North America
71 % were masonry block faced
65 % were 4-12?m high
91 % were geogrid reinforced; the other 9 % were geotextile reinforced
86 % failed in less than four years after their construction
61 % used silt and/or clay backfill in the reinforced soil zone
72 % had poor-to-moderate compaction
98 % were caused by improper design or construction (incidentally, none (0 % ) were caused by geosynthetic manufacturing failures)
60 % were caused by internal or external water (the remaining 40 % were caused by internal or external soil related issues)
In addition to presenting this statistical data, the paper also presents opinions and recommendations in several of the above areas particularly those which are felt to be at the core of why so many these structures are exhibiting performance problems. In general, the critical issues appear to be the following;
fine grained silt and clay soils used for the reinforced zone backfill,
poor placement and compaction of these same fine grained backfill soils,
drainage systems and utilities being located within the reinforced soil zone,
non-existing water control either behind, beneath or above the reinforced soil zone, and
improperly determined and/or assessed design details.
Concern over the situation has prompted the creation of an inspector's certification program, i.e., the .