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Author Topic: How Come Potholes Are Usually The Same Size ? (ish)  (Read 7569 times)

Offline neilep

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Dear Pot Holeologists,

As a sheepy I of course hate Potholes !..there's nothing worse than for me to ruin my Prada heels tripping in a pothole after coming out the club at 3am...

Look at these potholes.


Potholes earlier today....look at them !!..it's a joke innit ?


Can ewe explain how potholes occur  ?and why they seem to be the same size ?


What can be done to stop them ?



ewe see, I want to know this so that I can know it

thanks

hugs & shmishes


mwah mwah mwah !



neil
There's A Hole In My Bucket
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Offline Geezer

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How Come Potholes Are Usually The Same Size ? (ish)
« Reply #1 on: 04/03/2010 05:38:34 »
This is a very complicated subject. I believe Einstein studied this field for a while, but gave up.

However, I think it might be something to do with spring rates and the damping devices ("shock absorbers") on vehicles.

There is a possibly related phenomenon. The formation of "moguls" on ski runs. If ski runs are not groomed, they get all "mogully", and I hate moguls!






That's me hating moguls yesterday.
 

Offline LeeE

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How Come Potholes Are Usually The Same Size ? (ish)
« Reply #2 on: 04/03/2010 15:08:12 »
I wouldn't be surprised to find that there's a correlation between the sizes of potholes and the diameter of the tyres that make them.  Mind you, I wouldn't be surprised to find that there's no correlation either. ;D
 

Offline neilep

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How Come Potholes Are Usually The Same Size ? (ish)
« Reply #3 on: 04/03/2010 17:26:10 »
This is a very complicated subject. I believe Einstein studied this field for a while, but gave up.

However, I think it might be something to do with spring rates and the damping devices ("shock absorbers") on vehicles.

There is a possibly related phenomenon. The formation of "moguls" on ski runs. If ski runs are not groomed, they get all "mogully", and I hate moguls!






That's me hating moguls yesterday.

Thanks Dr Geezer

Did Albert really study that actual field geezer ?...gosh...he must have been a kewl skier !

I see, your second related phenomenon correlates with Dr leeE...so..it must be true !....Is it just a weak part of the road that succumbs to vehicle impact joyness  then?
 

Offline neilep

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How Come Potholes Are Usually The Same Size ? (ish)
« Reply #4 on: 04/03/2010 17:28:44 »
I wouldn't be surprised to find that there's a correlation between the sizes of potholes and the diameter of the tyres that make them.  Mind you, I wouldn't be surprised to find that there's no correlation either. ;D

Thanks Dr LeeE.

As mentioned above, Dr Geezer seems to concur....I just had it in my head that it had something to do with ice !...ewe see. I noticed a breakout of 1000s of potholes after the recent ice age we had a few weeks ago !....could it be that the ice preys upon an already weakened spot in the road made my vehiclmobiles ?
 

Offline Geezer

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How Come Potholes Are Usually The Same Size ? (ish)
« Reply #5 on: 04/03/2010 18:10:14 »
Yes. If there is a crack in the road surface that lets water in, when the water freezes the expanding ice breaks up the road surface. After that there is something about the dynamics of the wheels and suspension that ejects the material from that area to create the tyre wrecking pothole. It may just be the torque applied to the driven wheels that gets it started.

There is a similar effect called "washboarding" that happens on gravel roads, and that does seem to be associated with torque because it tends to happen more on hills.
« Last Edit: 04/03/2010 19:28:36 by Geezer »
 

Offline neilep

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How Come Potholes Are Usually The Same Size ? (ish)
« Reply #6 on: 04/03/2010 23:46:20 »
Yes. If there is a crack in the road surface that lets water in, when the water freezes the expanding ice breaks up the road surface. After that there is something about the dynamics of the wheels and suspension that ejects the material from that area to create the tyre wrecking pothole. It may just be the torque applied to the driven wheels that gets it started.

There is a similar effect called "washboarding" that happens on gravel roads, and that does seem to be associated with torque because it tends to happen more on hills.

Thank ewe geezer....now I fully understand !..I'm saluting my own comprehension....clearly if the average tire/tyre was larger or smaller then i gather correspondingly, the potholes would reflect that.
 

Offline LeeE

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How Come Potholes Are Usually The Same Size ? (ish)
« Reply #7 on: 04/03/2010 23:52:33 »
Oh yes, there's no doubt that the expansion of water, when it freezes, once it has seeped into a crack or crevice is the primary cause of potholes (not to mention the rather larger scale erosion of mountains and stuff like that).

I was just thinking about the size of the potholes though.
 

Offline doppler1

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How Come Potholes Are Usually The Same Size ? (ish)
« Reply #8 on: 05/03/2010 06:05:37 »
Hey Neilep,

I guess that, like life, some potholes are created more equal than others  ;D

This is a picture of a pothole that formed in Johannesburg in South Africa after rains in January this year and I think you would need to look around a bit to fins its partner.






« Last Edit: 08/03/2010 00:23:10 by neilep »
 

sharkeyandgeorge

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How Come Potholes Are Usually The Same Size ? (ish)
« Reply #9 on: 07/03/2010 21:14:18 »
Hi Guys I think I actually know this one potholes tend to be similar sizes because

1 your right its car tyres that determine the size of mature potholes (ones that have had time and wear)

2 diesel spills which cause most potholes on tarmac roads tend to be small and provide a ''corrosion indent'' which let the tyres get to work

3 ice plays a big part as witnessed on Scottish roads this spring however ice simply breaks the tar bonds and the cold temperature prevents reformation producing a small area of damage which tyres excavate. However as these potholes are normally found in repaired tarmac rather than virgin it tend to allow excavation in repair layers.

4 water is the biggest digger of the lot when an ''indent'' is swept by a car tyre, water pools in the cavity and due to a combination of shock travel and wheel torque the tyre is spun in the indent and scours the inside before the shock allows full travel. That's why pot holes stay small for a long time then once reaching a certain size in relation to the prevelant wheel size they suddenly seem to become much deeper very quickly.

hope that all made sense
 

Offline neilep

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How Come Potholes Are Usually The Same Size ? (ish)
« Reply #10 on: 08/03/2010 00:24:39 »
Hey Neilep,

I guess that, like life, some potholes are created more equal than others  ;D

This is a picture of a pothole that formed in Johannesburg in South Africa after rains in January this year and I think you would need to look around a bit to fins its partner.










Thank Ewe Doppler !

Holy Guacamole !!...that's the mother of all potholes !!
 

Offline neilep

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How Come Potholes Are Usually The Same Size ? (ish)
« Reply #11 on: 08/03/2010 00:27:10 »
Hi Guys I think I actually know this one potholes tend to be similar sizes because

1 your right its car tyres that determine the size of mature potholes (ones that have had time and wear)

2 diesel spills which cause most potholes on tarmac roads tend to be small and provide a ''corrosion indent'' which let the tyres get to work

3 ice plays a big part as witnessed on Scottish roads this spring however ice simply breaks the tar bonds and the cold temperature prevents reformation producing a small area of damage which tyres excavate. However as these potholes are normally found in repaired tarmac rather than virgin it tend to allow excavation in repair layers.

4 water is the biggest digger of the lot when an ''indent'' is swept by a car tyre, water pools in the cavity and due to a combination of shock travel and wheel torque the tyre is spun in the indent and scours the inside before the shock allows full travel. That's why pot holes stay small for a long time then once reaching a certain size in relation to the prevelant wheel size they suddenly seem to become much deeper very quickly.

hope that all made sense

Thank ewe sharkeyandgeorge for your corroborations and explanations.

Is it that roads in the UK are just...well...crap !! ?....do ewe think they have potholes on the roads in Germany where I think they have far superior roads !
 

Offline Geezer

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How Come Potholes Are Usually The Same Size ? (ish)
« Reply #12 on: 08/03/2010 08:33:19 »
It is well known that roads in Germany are made with "Tarmacadamuberconcretesteelsubstrateinplace"
 

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How Come Potholes Are Usually The Same Size ? (ish)
« Reply #12 on: 08/03/2010 08:33:19 »

 

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