math help ...

[John Pratt]

I got to go with Charlie on this one. I don't think I want to be planning my kids funeral but thinking "whew, at least the driver of that car is ok." In our area there was a family that lived at the end of a "T" intersection that had their house hit twice by people not seeing the turns at night. They installed the same pop-up security barriers you see at government facilities. They hit a button and they are down during the day, hit the button again and they are up at night when it is more likely someone will run the intersection. As long as you are placing this barrier on your private property and not on public property I don't see where the liability is. We're not talking about building man-traps, booby-traps, or something similar that would catch unsuspecting persons. We're not talking about a minefield, we're talking about a visable barrier that if you run into it, it is your fault and you assume responsibility for your actions.

[Brian Kent]

We had a similar crash spot a couple of blocks from our last home. In 7 years there were 4 major crashes in the same spot. 1 drunk driving - passenger killed. 1 driving high. 1 teenager fell asleep at the wheel (not drunk, but early in the morning), and 1 cause unknown but not dui.

[Charlie Stone]

I'm not sure you actually have any liability issue to worry about

In my city, you get a ticket for hitting a stationary object with a car. They also have the option of tacking on failure to maintain control of your vehicle. I have seen enough drunk driving accidents to not have much sympathy for the drunk drivers, who typically are unhurt after they kill someone. On Halloween a drunk killed a pregnant woman who was taking her older child trick or treating .. the woman died in front of her kid.

[Charlie Stone]

I haven't even tried to count or keep track of the car on car accidents at my corner. There is at least 1 per month. Going back more than a year, there has also been a tow truck that hit a tree, an SUV which rolled over (solo, very weird) a drunk who hit 3 cars and my tree then drove off, someone hit a no parking sign along the side of my house and ended up on the sidewalk. Most of these have happened when there was no snow or ice on the ground. Typically in the winter, since I am on a busy corner, all the snow gets piled from the intersections on my corner, and the plows create a nice 2' berm along the streets.

[alex grams]

Consider security planters. They are specific to what you are looking to achieve, though I don't know how they compare cost wise to large stones. They are more aestetic and probably a lot easier to mow/edge around.

In regards to stones:

I would not place a single larger boulder, but consider smaller ones (roughly 1 cubic meter). And place several in the line in which you are concerned the vehicles would come from, no further apart than the vehicle width at the indicant angle from which the vehicle would be traveling.

If the stone is granite, a cubic meter gives you about 6000lbs of stone. The only suggestion I can make as far as the stone is dont get a flat one, get one where you have at least a foot of height above an estimate impact from a vehicle (maybe 3' tall stone), that way a vehicle can't go over it.

Also, if you want to help prevent a vehicle from going over it, consider making a small mount along the line maybe 1-2 feet high and place the rocks on the apex, then the vehicle would come up into the boulder and have little chance of going over. Dig the dirt from in front of the mound that way you have a smaller depression in front of it to even further heighten the effect of the rocks/mound. The more you do this, the more comfortable you could feel with smaller rocks.

[Bryan Morgan]

In my city, you get a ticket for hitting a stationary object with a car. They also have the option of tacking on failure to maintain control of your vehicle. I have seen enough drunk driving accidents to not have much sympathy for the drunk drivers, who typically are unhurt after they kill someone. On Halloween a drunk killed a pregnant woman who was taking her older child trick or treating .. the woman died in front of her kid.

I'm with you. I have family who were killed by drunks. An F150 hopped into oncoming traffic and plowed head on into my cousin in his 3 series BMW. Killed him almost instantly and fractured the skull and almost killed his infant son. The driver of the truck was perfectly fine though, of course. To me, its the equivalent of murder, or worse. They make a conscious decision to drink, they accept %100 of the responsibility, even if it kills them. You must protect your family. I have no sympathy or empathy for anyone who gets killed while willfully doing something they know could easily kill them, especially drinking. I'd put whatever rocks and walls you need to protect your property and family from those losers.

[Kent A Bathurst]

Ya know, you are all right about this. Maybe I am not taking the drunks safety into account.

Allow me to rephrase the question. In physics, How many tons of feathers would it take to stop a 18 wheeler doing 10 miles per hour.

heh-heh-heh - very good, Charlie, very good.

Just put in some BDB [big doggone boulders]. See what the landscapers have. You don't have to stop 'em cold, you just have to deflect 'em, and let 'em ride up onto the reef. I'm with you. If the traffic is that dangerous - and it certainly sounds like it is - stop them from getting to your home + family. Rocks don't injure drunk drivers - drunk drivers injure drunk drivers. Give them a big body shop bill to go with the fine and the hoosegow - maybe they'll get the message.


As an alternative, you could go medieval or WW-II on your approach .

Good luck.

[John Coloccia]

re: drunks
I guess I was thinking of the non-drunk mom in the minivan that got distracted for a second with her kids screaming in the back.

re: the legality
There's usually setbacks for structures. Not sure how large boulders or security devices would factor into that.

[Steve Friedman]

From someone who barely remembers high school physics and chemistry -

How about a mud pit situated to grab the wheels of any drivers who veer off the road? The mud needs to be thin enough to slow the car gently, thick enough to get the car stuck (so the driver needs to get towed out), and sticky enough to leave a permanent mark on the offending vehicle to warn everyone about their driving tendencies - kind of like a modern day scarlet letter!

Just a thought.

Steve

[Charlie Stone]

as far as I know, no minivan mothers have been involved in an accident near us. Just drunks and people talking on cell phones.

[John Coloccia]

From someone who barely remembers high school physics and chemistry -

How about a mud pit situated to grab the wheels of any drivers who veer off the road? The mud needs to be thin enough to slow the car gently, thick enough to get the car stuck (so the driver needs to get towed out), and sticky enough to leave a permanent mark on the offending vehicle to warn everyone about their driving tendencies - kind of like a modern day scarlet letter!

Just a thought.

Steve

Do you think you'd need a permit for the drawbridge?

[Mike Cruz]

Charlie, to directly answer your question, I don't think it is so much a matter of the total mass of the boulder, more the height of it. A 20 to boulder that is only 5" high won't do the trick. A one ton that is 30" high, probably would. Even if it didn't stop it cold in its tracks, it would certainly slow it down enough to stop its momentum. What you probably want to avoid is a launch. So, look at guard rails. Measure their height. That is where I would start...

[Shawn Pixley]

I think you are over thinking this. How about large raised planters? Filled with dirt, a two to three foot high planter will stop a large truck. In commercial structures, these are often used to to stop the drive through (crash through?) robbery / burglary. Railroad tie, retaining wall CMU, or concrete planters will be both decerative and no one could accuse you of attempting to injure some one. Just trying to beautify your lot.

[Tim Boger]

Here is a suggested 20 ton boulder .... I figure it would stop an errant vehicle.

[Bryan Morgan]

re: drunks
I guess I was thinking of the non-drunk mom in the minivan that got distracted for a second with her kids screaming in the back.

If the mom is too distracted to be piloting a 5000lb+ lethal weapon she probably shouldn't be driving. These are lethal weapons, to be sure. Nobody accepts any excuses for accidentally popping off some rounds from an AK47 through your neighbors house while drunk, distracted, or otherwise. I don't mean to seem nasty or anything but vehicles are way too dangerous to be doing anything other than driving them. You can tell I drive So. Cal. freeways every day, and every day I'm dodging people doing anything other than driving. Heck, I've even seen guys reading the newspaper while eating a bowl of cereal, holding the bowl in one hand and the spoon in the other! No joke! I won't even go into the ladies driving land barges while yacking on the phone..... I pray to Darwin to make things right with the universe