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Comment by chrisseaton | Hacker News Reader

I don't think I saw any concrete structures when I was in Afghanistan. We used Hesco bastion for everything. I think even the furthest-back hospital was just sheet steel siding construction, surrounded by Hesco.

https://en.wikipedia.org/wiki/Hesco_bastion

Hesco is another very interesting material. Cheap, extremely light and easy to deploy, until filled, which can be done by anyone with an entrenching tool (small infantry shovel/spade that everyone carries) if required, and then basically indestructible.

How many of those concrete walls can a helicopter carry? One? It's going to take a long time to build any wall or structure. Or do you send an armoured cement mixer and create on-site? That's not realistic in a place like Afghanistan.

I'm not an engineer but I would also guess that Hesco survives better - a box of stones can lift up and crash back down with an explosion where if concrete cracks it's permanently broken.

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> I don't think I saw any concrete structures when I was in Afghanistan.

Seriously? You never saw the giant prefab concrete walls around Bagram and Phoenix, and Eggers? Where were you in Afghanistan?

I have been to just about every significant ISAF base (while it was still called ISAF, not RS) and US DoD base in the country, and can assure you that giant prefab concrete walls lifted into place with cranes are everywhere.

> Where were you in Afghanistan?

A FOB somewhere near Lashkargah. I never went to Bagram, Phoenix or Eggers. I spent a few days in Bastion, which, as the name suggests, was also constructed from Hesco bastion.

I'm guessing you never saw the Kandahar airfield, because that place is full of concrete barrier walls...

https://static01.nyt.com/images/2010/07/15/blogs/atwar-afgha...

> A FOB somewhere near Lashkargah

My Google-fu thinks FOB is short for Forward Operating Base.

Yup. For small units on the move (or operating all stealthy-like), you can airdrop a few C-containers (FOB-in-a-box) right at (or behind!) the front line and be up and ready to go in not-that-many hours.

I'm going to guess you weren't there, because the concept of "air dropping" a 20 or 40 ft container is pretty silly... Such a thing almost never happens.

FOBs are established by cargo that arrives by truck. The only FOBs I ever heard of being established by air cargo (Chinook, and in very mountainous regions of Kunar and Nooristan mostly) were not exactly what you would call a FOB in the context of Afghanistan, but were much smaller sites on hilltops that would be designated COPs (combat outpost) or firebases.

Our FOB was initially air-dropped into place (we had lots of spent one-use parachutes to show for it). I wasn't there then so I don't know how big the kit was, but yeah they weren't ISO containers obviously.

I was not there. I helped design power generation and radio-telecom systems & packaging for them. Now, it's not two C-containers on skids, to be sure! :-)

They were support for very (very) small sites. They were called FOBs by the airborne guys, but I don't know much about military terminology, and can't vouch for the correctness of the use of that term in this case.

EDIT: This doesn't look like what we worked on, but I just found this:

  - http://www.foxnews.com/tech/2011/12/02/military-base-in-box-all-rage.html

The Marines ran Helmand a bit differently than how the Army ran everything else.

The Army loves their t-walls. So much in fact they give out little awards that are shaped like t-walls.[1]

[1]: http://uswarriorsoutdoors.org/us/wp-content/uploads/2014/11/...

Wow...

You killed their website :)

Helmand province FOBs (at least when I was there) were Hesco barriers, artificial dirt berms 8+ meters high and trenches. Some FOBs repurposed pre-built infrastructure and reinforced it with Hesco barriers, but there was very little concrete. I'm sure it looks a bit different these days, but we did not have concrete in most AOs.

Farah (2009 - 2010) EOD tech reporting in. We were almost all Hesco too. Oddly, we found a lot of PMNs[0] in our Hescos.

[0]: https://en.wikipedia.org/wiki/PMN_mine

Woah! To clarify, when digging up filler for the Hescos, PMN was present in the area the filler was taken from and thus made their way into the Hescos?

Yes this was not uncommon, all kinds of shit was put into hescos. Unless an area was specifically swept for mines (time consuming, expensive and labor intensive) it was usually randomly selected topsoil.

I was/(am?) a bomb tech, I didn't dig up a damn thing, we were too highly valued of an asset..And only having a small handful of us to support an entire theater of war makes us exceedingly rare.

Got called out on quite a few. One in particular was a dude out at a COP in the middle of no where Farah, taking a piss next to a Hesco, looked up and saw a mine poking out of the barrier. Afghanistan is one of the most heavily mined countries in the world. It's not surprising.

Consider the terrain - an FOB in rural Afghanistan is going to have access to a lot of dirt/sand/etc to fill the Hescos, while simultaneously not having restrictions on wall depth due to existing infrastructure.

In a dense urban environment there isn't likely to be thousands of cubic feet of readily available fill material, and a 3-5 foot thick Hesco is going to be much more difficult to emplace than a 12" thick concrete barrier.

Hescos are different object for a different purpose. They are meant to stop inbound fire, not inbound people. Climbing over them is trivial, at least in comparison to a 3m tall concrete wall. Hescos are therefore useful only where they can be monitored. They are great for bases, but if you want to stop people from entering or exiting something as large as a city then you want something you don't have to patrol 24/7.

There is another upside to the Hescos. They are much more difficult to undermine (literally). They are relatively soft and will likely collapse any hole under them. Concrete structures don't slump and so can be undermined.

Hesco barriers were pretty wide spread in Iraq as well. Baghdad was the only place I saw where the concrete barriers outnumbered the Hescos.

Because hescos do not need logistical support 2 people can deploy one and fill it with sand and gravel even by hand if needed.

Hescos are also better since they don't cause ricochets and they don't shatter on impact creating shrapnel.

From my experience when concrete walls are used for fortifications the SOP was to cover them with a sheet of Kevlar like fabric between two layers of metal webbing (concrete bolt/nail gun was used to secure the webbing to the barrier) to protect personnel from secondary impact risks.

If that wasn't available then you usually had a layer of either sand bags or a spaced secondary wooden or sheet metal wall with sand filling the gap between it and the concrete.

When bullets are flying at you you want to be behind a barrier but not near a bare concrete wall.

Also, when heated/on fire cement will explode.

If it's not dry yeah, tho if you are taking in napalm you have bigger issues than exploding concrete.

would be interesting to develop a gluing agent to convert local gravel into a concrete like material that could be formed like Hescos but in thinner, taller L shapes for the purpose of erecting barriers as in the article.

drying would be the main issue, probably.

Cement plus sand, this is what most walls in the middle east are made of they are very soft tho, you can crumble them with your fingers if you get past the outer layer of plaster.

The upside is that they don't ricochet as much if at all, the downside is that bullets leave pretty large impact craters and if the wall isn't thick enough simply pass through like it wasn't there.

But the problem remains if it's hard bullets will ricochet and it will splinter into shrapnel, if it's soft it's not an effective barrier and the wear on it is very high.

Hescos or any other similar fortification are simple and effective, there is a reason why we still use sandbags and planks of wood with sand in between them, sand is a great bullet trap and you can shoot at hescos and sandbags all day long and you won't really do much damage. there needs to be a pretty big hole for the sand to sip out since it's kept in place by the pressure and compression.

Hescos also have a lower surface area to weight ratio. They are therefore much less likely to be moved by nearby explosions. And their softer insides make total failure, shattering, almost impossible.

On that note, i recall reading about a British project to produce quick rise shelters. They were basically a inflatable tent with cement impregnated outer canvas.

Roll out, inflate, soak in water, and wait for it to harden before releasing the pressure.

And such a gluing agent would be cement. Concrete is really nothing more than cement mixed with sand or gravel. The farm i grew up on had a barn where the foundation was nothing more than cement and small rocks from the land. It was built up like a layer cake. One spread of cement, then a layer of rock, repeated until desired height.

> On that note, i recall reading about a British project to produce quick rise shelters.

http://www.concretecanvas.com/

Their price (that I could find) quotes on old news sites were insanely high unfortunately (GBP15-20k).

It looks like the shelter use has been relegated to a secondary product vs the main use: rolls of the stuff for construction uses.

http://voices.nationalgeographic.com/2013/03/20/concrete-can...

> A Concrete Canvas shelter would cost 15,000 to 20,000 pounds, in the U.K., for a one-off ($23,000 to $30,000), but the price steps down if you are buying volumes.

My guess is that they're not interested in dealing with small-volume customers, and so for large volumes the prices descend to a much saner price. "Look at how much your government/military/refuge 'saves' when you buy 1000 of these!"...

Cement + sand is very different from cement + gravel + sand, and even then, the result varies widely depending on what kinds of gravel and sand you mix with the cement.

Sounds like you found a better war than I did, or at least a fancier one. Bare concrete was definitely the norm for our concrete fortifications.

You need to remember that the concern is less about bullets and more about mortars/rockets/VBEDs, which I can assure you, both types of barriers did a reasonably decent job of stopping.

Hescos seem like a better deal in terms of material moved vs material acquired on site. But they also seem like they would have to be wider to be stable, what that your experience? Pictures seem to have them as 3x - 5x the thickness of a concrete barrier of similar height.

Yeah they are considerably thicker, not really for stability but to be effective at stopping large penetrating and explosive projectiles and even acting as tank traps.

They are also slower to deploy, tho if you do it properly you dig both the obstacle outer ditch (which makes the effective height of barrier too high to scale) and trenches as you fill them since the ground needs to come from somewhere.

That said to deploy concrete barriers you need a crane, when push comes to shove a squad with shovels can fill a hesco.

Some concrete barriers can also be higher than hescos, tho you can stack hescos without much trouble.

Overall if you are building an FOB all you need is a few flatbed trucks and a bobcat (small earth mover) to pretty quickly deploy hescos, concrete barriers need heavy trucks (which also means proper roads, you won't be driving a truck filled with concrete barriers over soft terrain) and you actually need engineers (as in the military definition, not academically educated ones) to deploy them.

In an urban environment concrete can make more sense tho, you can't dig ditched to increase the height, can't dig up the ground randomly, and since concrete barriers are thinner they are more easily deployed in urban environments and it's not like you have issues with logistics.

Although it wouldn't surprise me if the pentagon somehow managed to airlift these barriers from the US to Iraq to be deployed in Baghdad instead of just contracting the local concrete factories.

I don't know if this matches your experience, but in theory you can deploy a big line of Hescos all at once:

https://www.youtube.com/watch?v=ZPuw-f8JMTw

> Although it wouldn't surprise me if the pentagon somehow managed to airlift these barriers from the US to Iraq to be deployed in Baghdad instead of just contracting the local concrete factories.

What, pay hundreds of thousands of dollars and countless gallons of fuel to transport big concrete blocks across the world? Our DoD? Surely you jest. 8)

Well that's a cool thing, but no never seen that being used tbh, while it's fast, it also means you need some extra things, which also means planning ;)

This is more in line with how usually these things are deployed. https://www.youtube.com/watch?v=o_lsmE_EwEE

If it's more organized it's usually means it's deployed by the engineering corps or a contractor anyhow.

That's a pretty great way to deploy empty barriers, but what I'd love to see is a machine to fill them even a quarter as fast as they can deploy them haha

The perfect harmless prank: deploying a shipping container of Hescos in a densely populated area.

The title states "modern" battlefield, which I believe they are equating to a more urban enviornment -- than a outpost in Afghanistan. The use of concrete walls to segregate a city into sections is the main benefit. This article is rather anecdotal and appears to just be the opinion of the author.

Traditionally with nation state opponents urban warfare is either a siege or blowing up everything in sight.

With this lower intensity warfare, the army needs to reduce complexity by scoping their problems.

This isn't new. That Boer war reference left out a few details... the British couldn't defeat mobile cavalry with pack howitzers, so they built fences, pillboxes and watchtowers across the countryside to restrict movement. Then they evacuated towns and villages to concentration camps and starved the non combatants until the soldiers surrendered.

It's a pretty common theme used in the Indian wars and vietnam by Americans, Germans in Angola and Europe, French in Algeria, etc as well.

The article says

> Existing structures [abandoned buildings] surrounded by walled compounds of some type were selected because there was little in the environment to use for protection—such as dirt to fill sandbags, earthworks, and existing obstacles.

so that might be part of the reason.

I'd imagine you'd have a hard time using Hesco barriers in an urban environment. One, they're too big. Two, you'd have a hard time finding loose fill. And three, they're slower to deploy.

Isn't Hesco basically a modern sandbag?

A gabion is what you are thinking of

Reminds me of reinforced earth which I learned about from this video: https://www.youtube.com/watch?v=0olpSN6_TCc (which is also from the pretty great Practical Engineering channel).

They mention the reason for not using Hescoes in passing in the article. In the cities there wasn't an easy source of dirt to fill them so it would have required trucking in a lot of the dirt to fill them.

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