Building endurance

[John O'Reilly]

For some time now I have been perplexed with the relative ease in which buildings may be destroyed by tank fire. In a recent game for example, one Panther demolished a light building with one minutes fire. Whenever I encounter infantry in buildings I simply destroy the building. In fact I tend to do so as a rule to any building that presents a good observation post for the enemy. My question is simple, were buildings really that vulnerable to direct fire?

[ParaBellum]

When talking about buildings, you have to differ a little bit. What does a light building in CM represent? It's just a wooden shack, a humble abode.

I've seen movies from WW2 eastern front where a single hit by an 88mm caused wooden houses to literally explode.

It's quite different with stone buildings or large buildings. They can absorb more damage and can protect the infantry better.

And never forget, a house standing in the middle of a field isn't a very good place to be when enemy armour comes by...

I once saw a wooden building under fire by a Bundeswehr Marder. After 5 minutes of firing the hut was reduced to rubble. And the Marder carries only a 20mm gun.

Many players knock down every building with good LOS. It's a sound tactic especially when you got some support tanks with 105mm guns that will shred the buildings in no time.

When playing less experienced players you can usually count on them placing their FO in the tall building on the only hill...

[Wreck]

Nonetheless, the building modelling in CM is a great problem. In part because of borg sighting, and in part because area fire is allowed, you get the ability to knock down buildings to attack infantry that you cannot see. Buildings in WWII were not perceived by the infantry as fearful deathtraps; quite the reverse.

IIRC CMBB is going to tone down the borg sighting somewhat, though I don't recall how. This will help. I might suggest adding a rule giving a good chance that units not accept orders to area fire on areas that are barely visible.

Ideally, buildings could be rubbled bit by bit. However I doubt that will happen.

Failing that, I would prefer that BTS drastically reduce the casualties taken by infantry in buildings that detonate. They might then increase the blast effect of rounds hitting buildings somewhat, but only against infanty in the same building, which would model men being affected by collapsing parts of the building.'

[JasonC]

The buildings certainly rubble too easily. Especially in two cases - the biggest stone buildings, and the effects of quite small projectiles. Part of the problem seems to be the purely linear way impacts seem to add up. This lets 16 times as many small projectiles do far more than the should, relative to a few much bigger ones.

Ideally, some sort of square root thingie might address this. The stuff 155mm and up HE does to buildings is reasonably believable. The stuff 105 does is stretching, the stuff 75 does is getting to "huh?", especially for big stone targets, and by the time you are down to quad 20mm you are on the floor laughing.

It would also be great if there were some modeling of cellars. They were the prime attraction of buildings to infantry, even after a building had been largely reduced to rubble. They provided significant protection against everything shy of a direct hit by high caliber artillery. Indeed, the infantry had to be sent into a town worked over by HE, precisely because no amount of HE thrown could dig men out of the cellars, while a few well placed hand grenades could.

[Kwazydog]

Originally posted by Wreck:

Buildings in WWII were not perceived by the infantry as fearful deathtraps; quite the reverse.

To be honest wreck, Im not sure if this is quite the case.

There is a chapter in the German Military Handbook on defense and one section discusses how the Germans would defend a town. In there it details that the Germans would often defend towns from the second or third row of buildings because it wasnt uncommon for the outer building to be destroyed by the attacking force. Its quite an interesting read actually...I believe someone posted it here some time back if you do a search.

Dan

[Redwolf]

Whatever the outcome here is, people shouldn't forget that building quality and stability varies greatly. I think people living exclusivly either in the US or in older European cities cannot imagine how different building of the other side can be. It also makes a big difference that the post-war years have seen a lot of concrete construction works, WW2 times were much different. Also, a light wooden house would not collapse as easily (and be as dangerous) as a badly built stone house, so "light" and "heavy" doesn't cut it either.

I guess what we really want is more variance and inpredictablity. If people want to knock down a building, but don't know whether they might have to invest the ammo load of a Priest to do so, they won't do the precision-timed demolition business they do now. If Charles could just drop an "endgame randomizer" with big variance into the rounds that might fell the house, I think the bitching would be lightend alot.

If there is some real demand for data, I know a building-statics engineer who happens to be an artilleryman in military service. It would be a hassle to ask, though and there is no guarantee that he can make a useful connection between blast and force on the house (but I guess so).

[Wreck]

There is a chapter in the German Military Handbook on defense and one section discusses how the Germans would defend a town. In there it details that the Germans would often defend towns from the second or third row of buildings because it wasnt uncommon for the outer building to be destroyed by the attacking force. Its quite an interesting read actually...I believe someone posted it here some time back if you do a search.

Searching has not been working for me recently, but I can address the point at least tentatively without reading the referenced material.

It is a reasonable and expected thing that HE hitting buildings will potentially hurt infantry in them; I am not zany. So the explanation for defending a bit back would simply be to not be in the most obvious defensive positions, since they are likely to be worked over at range by enemy direct-fire area HE. Survivability in the outer buildings could easily be better than it is modelled in CMBO without being anywhere near 100%, and no infantry commander would want to take, for example, 20 or 30% casualties without being able to reply.

In any case, defending two rows back from the edge is still defending in buildings. I realize that part of what attracted infantry to buildings in a lot of cases was the chance to be warm, but the cover afforded was certainly a factor.

[Wreck]

I agree with Jason in re: cellars. One way to approximate their effect would be to make a special rule case, where infantry that are hiding on the ground floor of a building with a cellar are assumed to be mostly down there, and therefore get their exposure number reduced, perhaps halved. The hiding represents the inability to fire when down there, of course.

[Redwolf]

Originally posted by Wreck:

I agree with Jason in re: cellars. One way to approximate their effect would be to make a special rule case, where infantry that are hiding on the ground floor of a building with a cellar are assumed to be mostly down there, and therefore get their exposure number reduced, perhaps halved. The hiding represents the inability to fire when down there, of course.

That would also blend well with the cover code for walls. Infantry behind a wall gets 0% exposure when lying down, and also can't fire. The same could apply when in a house.

But I am not sure we can make the cellar versus lying assumption since that would cause every lift in supressive fire to cause the people storming up the stairs and back on a too frequent basis. Also the player cannot force his men to hide when enemies are near.

[Wendigo]

One kilogram (~2,5lbs) of C4 (or equivalent) can destroy light wooden building. I've seen it done. Now if you compare that to TNT or Amatol where same mass creates more gasses with lower detonation velocity the effect could be even more devastating.

The explosive block was just put simply on a desk in the house (2 rooms, ~50m^2). The walls just blew off and the house collapsed.

I'm not sure how shrapnel would add to this. basically it is the overpressure that breaks things in these kinds of situations.

If I remember correctly from my training (combat engineer) the most difficult buildings to blow up are solidly built stone buildings whereas wooden shacks would be the easiest.

On the second hand, if house is just built by stacking stones with low-quality mortar I suppose those would collapse nice and easy.

[John O'Reilly]

Thanks to all who responded, I will continue to be surprised by the ease with which buildings (of whatever construction) are destroyed. At this point is is standard operating procedure for me to destroy every building that may remotely contain a threat.

I find this especially effective as the Allies given the large number of Shermans often present with their high HE loadout.

I have always thought, when looking at the ruined cities of the second world war that this effect was achieved indirectly, by air and artillery, not by direct fire but it seems I was mistaken!

[Battlefront.com]

There are several accounts by Sherman vets about leveling houses with just a few shots. So inspite of Jason's insistance that this is a joke, we think not.

Small buildings were designed to withstand certain forces, such as wind and (in some cases) heavy snow. I have seen, first hand, what poor construction standards result in when either of these two forces have a good go at the structure. But I digress...

The point is that no house in Europe was designed to withstand a direct or indirect fire attack from anything other than wind, rain, and possibly snow. Anybody who understands the basic principles of structural engineering understands that in order for a structure to withstand an strong unanticipated force it has to be either a) over engineered, or lucky.

Look at the World Trade Center buildings. Two of the biggest, best constructed buildings in the world. They were also SPECIFICALLY designed to withstand the impact of a 747 (or some other large bodied jet) without catastrophic failure. Yet look what happened to BOTH buildings when each was hit by a smaller plane.

I also know from personal experience (my father is an engineer and builds buildings) that if you want to reduce damage from an explosion from within, you need to design a strong reinforced frame with walls which are intended to be easily blown outward. This is a common thing for chemical labs and other such facilities. General commercial and residential structures are not designed this way, so an internal explosion is likely to cause far more damage because of the containment principle (i.e. gunpowder on a plate burns, tightly wrapped up in paper it explodes).

Now, who here is silly enough to tell me that a couple of local house builders (often the owners, and not trained engineers by any stretch!) would have designed their houses to withstand a 75mm HE round fired directly into it? Cinderblock houses, with correctly mixed concrete, are one thing... but loose stones mortared together decades, or even centuries, before aren't the same thing. Wooden houses are in a league of their own.

Are CM's buildings detailed to the fullest extent they should be? No. Are they close? Yes. The reasons why they are wiped out too easily in CM battles is probaby more to do with "gamey" tactics rather than there being anything inherently wrong with the simulation. In real life forces did not try to destroy structures they were poised to capture or hold becaue they have value which outlasts the individual battle they are in. But in CM... who cares about what happens after the battle? There is nothing we can do about this either.

Steve

[The_Capt]

Steve,

Beg to differ but depending on the construction a building can be a pretty tough structure. I suggest you and the boys spend some of your profits and take a trip to Croatia. Go up around Vukovar or Osijek, there are plenty of building left with holes in em. Brick and mortar can take a fair amount of damage before total collapse. Wooden ones usually start on fire.

The question is on the detonation of the explosive. If it occurs inside of the bldg it will cause more damage. Problem is I don't think many tank rounds had delayed fuzes on them. HESH rounds slap up against a wall and make a lovely hole. Heat round blow a smaller hole but to a great job of room clearing and AP rounds simple tear thru the structure.

Now as to CM, I think it is a game abstraction as no two houses are absolutely identical. I also think that the wooden ones stay up a little too long but the stone ones "feel" about right. I do agree with Jason on the min calibre thing though. I have seen 40mm AA rounds wail on a "heavy" bldg for a couple of hrs and it was still standing at the end of the day.

[Gordon]

Originally posted by Big Time Software:

Look at the World Trade Center buildings. Two of the biggest, best constructed buildings in the world. They were also SPECIFICALLY designed to withstand the impact of a 747 (or some other large bodied jet) without catastrophic failure. Yet look what happened to BOTH buildings when each was hit by a smaller plane.

I also know from personal experience (my father is an engineer and builds buildings) that if you want to reduce damage from an explosion from within, you need to design a strong reinforced frame with walls which are intended to be easily blown outward. This is a common thing for chemical labs and other such facilities. General commercial and residential structures are not designed this way, so an internal explosion is likely to cause far more damage because of the containment principle (i.e. gunpowder on a plate burns, tightly wrapped up in paper it explodes).

Steve,

Just a couple of clarifications on some of your points above. I can't speak to whether the building modelling in CM:BO is correct or not, as I haven't acquired a large enough sample of European buildings to test against and ordnance to test with.

The World Trade Center was engineered to survive the IMPACT of a 707, which it did. Nobody thought to engineer it (if it's even possible to do so) to survive the intense heat from a full load of burning jet fuel. The buildings collapsed because the steel melted and failed, not because of the impact.

Another example of "blow-out" engineering is the modern M1 MBT. The armor panels around the ammunition storage area in the back of the turret are engineered to blow off to dissipate an ammunition explosion, rather than focusing it inside the turret.

Gordon

[BeauCoupDinkyDau]

Originally posted by ParaBellum:

When playing less experienced players you can usually count on them placing their FO in the tall building on the only hill...

Yeah, Ted taught me that lesson real quick when he demolished a town I was holding. I of course had 1/3 of my soon-to-be-dead-by-Ted's-howizers men in them.

[BeauCoupDinkyDau]

Originally posted by Big Time Software:

Look at the World Trade Center buildings. Two of the biggest, best constructed buildings in the world. They were also SPECIFICALLY designed to withstand the impact of a 747 (or some other large bodied jet) without catastrophic failure. Yet look what happened to BOTH buildings when each was hit by a smaller plane.

I saw a good program on this the other day. They were designed to withsatnd the impact of a 707 at level crusing velocity (presumibly lost in the fog with altimeter failure). The 767's are much heavier and were flying with their engines at max power. They were also fully loaded on avation fuel and the engineers did not take fuel into account when designing the structure.

Rat bastard jihad terrorists. I hope we swing'em like we did the nazi leaders! :mad:

[Battlefront.com]

Capt,

Yup, seen many pictures of these buildings. I've also been to Croatia and stayed in some of the same places that got mauled in fighting. Also been to various places in Western Europe. While I agree that some of these houses could take a pounding and still survive, I think there is an inherent structural difference between pre and post war structures as well as those in former Yugoslavia and Western Europe.

I also wonder how much large, direct fire low velocity HE was focused on the buildings during the breakup of Yugoslavia. A high velocity round would probably do less damage than a low velocity one simply because the latter would probably be on its way out when it detonated.

Again, when we researched this stuff 2 years ago we found some accounts of Sherman 75s saying that they found most houses could be leveled with only a few shots.

I do agree, and didn't say anything to the contrary above, that some structures could withstand quite a lot of punishment. I also agree that the modeling of CM's buildings are missing same shades of gray which would account for buildings being mostly blown out, but still having a wall or two standing.

As for some sort of "if round = less than x, then do no damage to building" routine... I dunno about that. While you saw a 40mm AA gun do nothing to one house, ParaBellum saw a 20mm gun demolish a different one. Obviously one was stone and the other wooden, but it does show that we need to be carefull when making assumptions. However, I tend to agree with the principle that a small, high velocity HE round fired against a stone/brick structure will likely ventilate it really well, but not bring it down. Anybody know how long it takes these types of weapons to cause such damage in CMBO right now?

Gordon,

I am aware that the fuel was what destroyed the buildings, which is exactly my point. The buildings were engineered to specifically withstand major forces yet were still not up to the task when hit with a real world situation. A house is not designed to withstand *any* sort of explosion at all, so it doesn't surprise me at all to think that something like a 75mm HE round could cause catastrophic damage.

Steve

[ February 13, 2002, 01:31 PM: Message edited by: Big Time Software ]

[aka_tom_w]

Hell Has No Heroes by Wayne Robinson © 1962

Describes the action of a DD tank that landed on Omaha beach. It is a Great book written bey someone that was there.

The book describes in accurate detail ALL kinds of things about the Sherman DD tank.

it tells how the crew ROUTINELY knocked down brick and stone buildings by blasting a round of AP into the wall near the corners and then quickly following up by pumping a few HE rounds through the hole without moving the tank or the gun. If that did not knock the place down they would fire another AP round to make a new hole and the pump a few more rounds of HE into it. This procedure was used to knock buildings quite quickly.

The BEST book I have ever read about tank combat from the perspective of a Sherman tank crew post D-Day in the ETO is "Hell Has No Heroes" and the book is NOT a work of fiction, but it reads like a novel because it is told like a story, but the author states that it was his experience he was writting about and all the events actually happened to him or the men and tanks around him as told. It is out of print but you can order it on the internet. My copy only cost me about $8.00 US (cheap by may war book standards)

-tom w

[CMplayer]

Originally posted by Big Time Software:

Anybody know how long it takes these types of weapons to cause such damage in CMBO right now?

I tested this a while back, and a wirbelwind knocks down a large stone building in 1-2 minutes, iirc. I posted about it, because that is really absurd. Jason is right about the mistake being that building damage is summed linearly based on the blast values.

[Battlefront.com]

I'll see what I can do about getting some changes made regarding linear damage modeling. However, keep in mind that Rarity should radically reduce the kinds of gamey use of AA guns we have seen in CMBO. Obviously this in and of itself is not a fix, but when one side of the equation is unbalanced, it will cause stress to the other side at the very least. Smooth out one side and the balance tends to be better without doing anything to the other side.

Steve

[leakyD]

Are CM's buildings detailed to the fullest extent they should be? No. Are they close? Yes. The reasons why they are wiped out too easily in CM battles is probaby more to do with "gamey" tactics rather than there being anything inherently wrong with the simulation. In real life forces did not try to destroy structures they were poised to capture or hold becaue they have value which outlasts the individual battle they are in. But in CM... who cares about what happens after the battle? There is nothing we can do about this either.

Steve-

An idea just popped up:

What about as part of the rewrite (and as a "realism" option), points during a battle are given/taken for said tactics.

that is: I might destroy the town and take it, but the negative points incurred makes the battle a draw (or worse)!

might help to "encourage" folks to use more realistic tacts as part of a "realism" setting (which, again, would be optional).

this would be esp. interesting if the rewrite ever came back to barbarossa: those germans *really* needed those buildings!

just a thought....

[John D Salt]

Heheheheheh.

Can open, worms everywhere.

ISTM that CM:BO concentrates, not unreasonably, on fairly-mobile warfare in the fairly-open countryside. This is traditional in wargames; it's more fun that slogging through belts of concrete fortifications or mouseholing from house to house, which is more like seige warfare. To be fair I think it's also by far the more common mode of warfare in the NW Europe campaign; I don't think there was very much in the way of large-scale FISH (Fighting In Someone's House -- a much nicer term that FIBUA, OBUA or MOUT); Aachen and Oosterbeek spring to mind, but not much really comparable with Stalingrad, Cassino or Ortona. Likewise, fighting through elaborate fortifications was a rarity, occurring only really during the intial invasion (and tidying-up battles like Cherbourg and ) and around Metz and Walcheren. So one can argue that leaving FISH and fortifications largely out of consideration is not unreasonable -- certainly no more unreasonable than, say, omitting amphibious vehicles, which one really needs only for the Rhine crossings, Walcheren and the Reichswald battles.

And yet -- it would be nice to have more elaborate constructions. Even simple field entrenchments might be more elaborate than the slit-trenches modelled in CM:BO; it doesn't take much in the way of engineer stores to produce overhead cover giving you pretty good protection against medium mortars and field artillery (and *why* can't I follow gunner tradition and put my OPs in church spires, eh?).

If you've got a house, you can make yourself really cosy given time to prepare it for defence -- demolish the stairs and replace them with ropes so that the bad guys can't get to the upper floor, keep the bath filled with water so you can fight fires, turn the cellar into a deep shelter. You can even do what the Canadians did at Ortona and remove the back wall of a row of houses, so that the Fallshirmjager entering what they thought was an intact house are left facing a space where the wall was and the muzzle of a previously-emplaced 17-pounder.

Concrete-and-steel fortifications would be even more fun. Certainly a subterranean terrain editing option would be needed in the map editor if one was to produce the intricate interconnected galleries of strongpoints like Morris and Hillman. This sort of thing also gives more point to "funnies" like the AVRE and Crocodile (and I'd really like to be able to drop fascines in anti-tank ditches or drive Churchill ARKs into them, too). Let's face it, CM is going to need to handle subterranean features if it's going to tackle the Japanese in the fullness of time, so may as well bite the bullet now...

(The question of demolishing constructions with HE, by the way, really depends a lot on fuzing. I'd like to see the difference between superquick and delayed action modelled, and let people try things like ricochet fire. But have you ever heard of any set of wargames rules in any medium that attempts this at all, never mind does it accurately? Me neither.)

Modelling all this (I'm deliberately not thinking about how much work this will take) will give more point to the engineers, and, who knows, maybe even make flamethrowers useful. And, while we're doing the engineer stuff properly, why not model demolitions (I find a game based on a demolition guard is normally good fun -- get your people back over the bridge, then blow it), and give use a proper selection of different kinds of mines and wire (triple-roll Dannert in the open, low entanglements for the bushes).

I'd be prepared to wait three years and pay $100 for the resulting game if it did all that lot well. But would anybody else?

All the best,

John.

[leakyD]

Are CM's buildings detailed to the fullest extent they should be? No. Are they close? Yes. The reasons why they are wiped out too easily in CM battles is probaby more to do with "gamey" tactics rather than there being anything inherently wrong with the simulation. In real life forces did not try to destroy structures they were poised to capture or hold becaue they have value which outlasts the individual battle they are in. But in CM... who cares about what happens after the battle? There is nothing we can do about this either.

Steve-

An idea just popped up:

What about as part of the rewrite (and as a "realism" option), points during a battle are given/taken for said tactics.

that is: I might destroy the town and take it, but the negative points incurred makes the battle a draw (or worse)!

might help to "encourage" folks to use more realistic tacts as part of a "realism" setting (which, again, would be optional).

this would be esp. interesting if the rewrite ever came back to barbarossa: those germans *really* needed those buildings!

just a thought....

[Steve McClaire]

IMO, the fact that buildings are slightly easy to knock down is not the whole problem. What seems 'unrealistic' to me is the way building damage is 'all or nothing' -- either the building is fully intact, or it explodes like a bomb and collapses to rubble. While some buildings might have a sudden, catastrophic collapse like this, I would expect most would gradually be reduced to rubble and not fall down in such a dramatic and damaging (to the units inside) way. It's also irritating when infantry will automatically run out of a damaged building as it nears catastrophic collapse -- usually right into heavy fire, which kills them. I think both contribute to the lack of realism. In most cases (especially large heavy buildings) infantry should be a lot better off just hunkering down in the building as it's being shelled, and not suffer horrendously when the entire thing is finally reduced to rubble (unless maybe they're on the top floor or something). If this happened then how much damage a building can take wouldn't be as much of a gameplay issue.

[Battlefront.com]

leakyD, yes... this probably the most important way to control destruction of structures, fires to forests, etc. This would be linked to whatever operating parameters your virtual commanding officer gave to you. Could be that you are allowed to knock down whatever you like

However, there will be other changes in the rewrite which will also, indirectly, help in this manner.

John,

Thanks for the thoughts. It is simply a matter of time and priorities. To simulate everything "right" would take decades. Structures are, in many respects, a black hole when it comes to development time. So even after the engine is totally rewritten there will still be major abstractions. However, many major improvements are absolutely being planned on.

Steve,

Buildings do suffer intermediate damage. It just happens that at some point the building will suffer a catastrophic failure. I don't see anything wrong with this, except perhaps it is too easy to do in some cases and/or due to gameplay limitations.

As for guys running out of dangerous structures... do a Search and you will find out why this behavior was *added* at user request No matter how bad you think it is now, the bulk of CM players who voiced opinions felt it was worse before the behavior was added. So it will stay in CMBB

Bottom line is that if you position your infantry in buildings, make sure the enemy isn't capable of pounding them into dust. Urban fighting is not easy for either attacker or defender in real life and in the game. I remember reading about an entire US Infantry Platoon wiped out when a Tiger scored the final "kill shot" on the rather large building they were all fighting out of. I think only two men survived, one of which went crazy, picked up a Bazooka, and CHASED the Tiger down the street. He didn't wind up killing it, but he did splatter a few grenadiers who happened to be standing in front of it when he fired.

Steve