Deadly retaining wall

An engineer is concerned about the dangers from inadequately constructed brickwork and blockwork. They cite the case of a blockwork retaining wall, about 2.5 metres high. It was built around the mid 1990s and consisted of hollow 200 mm blockwork, which was partially filled with concrete, but had no reinforcement. This of course was not readily apparent. Backfill behind the wall was poorly placed and for this reason did not put sufficient load on the wall to cause it to collapse, though there was a certain amount of cracking.

Shortly after a contractor started work adjacent to it the wall suddenly collapsed causing a fatality. The reporter cannot conceive that an engineer had anything to do with the original construction. To them it emphasises the need to get across to the general public, including in particular small relatively unskilled contractors, the importance of proper professional involvement in work of this nature.

The reporter’s own very strongly held view is that except perhaps where specifically engineered, and where high quality workmanship can be ensured, no masonry wall should be built 100mm thick to any height greater than 450mm. They think the ODPM (now Communities and Local Government) leaflet is along the right lines and free copies of this or a similar leaflet should be readily available in all DIY stores and garden centres. Whatever is produced their view is that it should contain, in large red letters, the message that walls are potentially dangerous, and that for any wall higher than say 1m, or any wall retaining more than say 300mm of backfill, professional engineering advice should be obtained.