In my location we have several Pill Boxes with an outer wall of brick I read that brick was used as shuttering in order to pour the concrete inner wall Instead of taking down the brick they were left in situ On the Eastern Command Line, we may have 5 boxes in a line, but just one would be brick ? I seem to recall and I cant think where, that brick walls were superior as it absorbed artilary fire better than concrete ? Can anyone shed any light on this for me ?
Alan, A brick wall would not stand the pressure of a concrete wall poured behind it.You would need an outer and inner form,properly braced to withstand the pressure. Looking at your picture,it appears to be brick faced facade.It would have little strength. As to its ability to absorb impact,who knows. Bob
Hi Alan, welcome to the forums. Here's a link to the Pillbox Study Group which will help you- www.pillbox-study-group.org.uk/ Think I'm right saying the prewar British "bulletproof" standard thickness was 39 inches, hence the brick shuttering and concrete infill. A lot of pillboxes were reinforced with steel rebars, so they would have had a steel 'skeleton' surrounded by corrugated iron or wooden shuttering while the concrete was poured. Around 1942, a lot of pillboxes (usually Types FW3/22 and FW3/24) were modified by having extra concrete added to the walls under the embrasures, and an extra slab added to the roof which stopped just before the wall edges. These were known as 'shellproof'; there's one at Crail airfield in Fife which looks like Bertie Basset due to the extra slab on the roof. I know there were tests done on various pillbox types to determine just how 'shellproof ' they were, but can't remember seeing any published versions. Think this happened along the Kennet-Avon canal.
In 1999/2000 a Military Historian for Essex County Council surveyed every WW2 Defence structure in the county He stated bricks were used as shuttering where they were prevalent, due to the proximity of local brickworks Here in Bures, there are numerous brick faced Pill Boxes and co-incidentally we had flourishing brick works. 5 miles up the road was and still is, another brickworks Must have been time consuming building a brick wall, instead of timber shuttering ? I was wondering if bricks were used where there was No source
Yes, I take your point:- the loading on the brick wall must have been tremendous with 2ft+ of concrete behind it Ex army Major in the vilage told me yesterday, a decent Rifle Bullet would go clean through a brick wall. It certainly would not stop an Artiliary Shell
That's a possibility. The massive programme of building caused a shortage of materials, bricks would have been the only alternative where there was a shortage of concrete.
....here's a 30-06 video hitting brick,,if you look closely, and stop the video before the round hits, the brick ''wall'' looks very flimsy
Henry Wills's excellent (classic, even) Pillbox book says there was indeed a timber shortage that led to the WO approving the use of brick for shuttering. Detailed specs of mortar & thickness laid down, (largely concerned with maximum economy of cement, as the intense building programme had placed such stress on supplies). He refers to the specs: "Where enemy fire was expected, the walls were to be of 1:2:4 mix (concrete) with the full thickness retained. For walls not so exposed, a 1:3:6 mix, or a 9 inch brick wall with earth or rubble backing was considered sufficient" Shuttering brickwork was specified to use the same 1:3 mortar mix as set for below ground work. Sometimes you see boxes with a rough finish left where time has claimed the bricks. They weren't really envisioned as any competition for concrete, more a compromise in time of pinched supply.