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View Full Version : somebody that knows about trucking please do a BS check for me



chad
12th December 2011, 11:24 AM
this article implies we are all going to die if the new 97,000 pound trucks are allowed on interstate bridges, because they were designed for 80,000 pound trucks.

fear factor on this one? or another thing i should add to my list (avoiding interstate bridges).

palani
12th December 2011, 11:27 AM
I used to live in fear when driving hwy 30. They had a bridge marked "SAFE FOR ONE TRUCK ONLY" and I knew I was not in that truck.

Dogman
12th December 2011, 11:34 AM
Highway surface overload, bridges and such. The overloaded trucks will quickly destroy/screw up the roads. Palani there are some weight limited bridges here out in the county's around me, that WILL make your bunghole just plane disappear, driving over them.

midnight rambler
12th December 2011, 11:37 AM
This is nuts as the already crumbling, under-maintained infrastructure can't and won't handle the wear and tear of the 21% increase in weight.

solid
12th December 2011, 11:40 AM
This is nuts as the already crumbling, under-maintained infrastructure can't and won't handle the wear and tear of the 21% increase in weight.

Maybe the trucks just need to drive extra fast over these bridges. Speed limit 65 on the interstate for trucks, 95 going over bridges. :)

mightymanx
12th December 2011, 11:55 AM
It depends on PSI that the trucks have you are allowed an amount per axle* and the amount of tread on that axle 500 pounds per inch of tread with. So weight increase that does not contribute more to ground pressure is pretty much a non event untill thigs with an absolute value like bridges etc.

Most 4 axle trucks (1 front 2 rear with a dropdown) and 4 rear axle trailers are running around 110k pounds already.

Roads, bridges and tunnels are dynamic structures we have been maintaining them poorly since they were created because maintaining stuff is not sexy and will not get people re-elected so we have been letting it all go to pot for about nearly a century now (most dams are 100 years old).

With more people living dependent on cities AKA trucking centers and the increase of fuel costs combigned with the chokehold the government puts on the industry with rules and regulations. The logical answer would be to increase capacity per truck. because you can't increase hours per day driving or physical size due to existing rules. Or you could rely on governement subsidy to be profitable like other countries. The trucking industry is on the decline like every single other aspect of this country.

What to do??? Air drop food into cities?? Nationalize trucking??? Expect people to work for free???? Have Drivers drive longer than 10 hours per day???? Something has to give.

I think that the plan is the best compromise allowed.


http://ops.fhwa.dot.gov/freight/sw/overview/index.htm

* federal interstate laws for weights may be more restrictive on a state by state basis and on non interstate roads.



Federal commercial vehicle maximum standards on the Interstate Highway System are:
Single Axle:20,000 poundsTandem Axle:34,000 poundsGross Vehicle Weight:80,000 pounds

madfranks
12th December 2011, 12:09 PM
http://www.youtube.com/watch?v=wmAPSJsm-lc

po boy
12th December 2011, 12:39 PM
H Palani there are some weight limited bridges here out in the county's around me, that WILL make your bunghole just plane disappear, driving over them.


AKA pucker factor lol

gunDriller
12th December 2011, 01:09 PM
AKA pucker factor lol

i had a pucker factor experience when i pulled an overweight truck into a Cal Highway Patrol weigh station.

the law is, you can use a regular license for up to 26,000 pounds.

i was a few thousand pounds overweight.

for that you're supposed to have a Class A license, i was informed.

i won't say the number of laws i broke, i don't want to jinx my good luck - they let me off with a warning.


one of the many truckers i talked to was carrying 80,000 pounds. it sort of pissed me off because he got 7 miles per gallon - and that's what i got with 1/3 the weight !

i could tell he took his work very seriously.

the opportunity to do a huge amount of damage in a short amount of time is there every second with a vehicle that size.

i came around one corner driving in the dark, there was a truck with a trailer stopped on the right - all the way onto the shoulder, but 2 feet into the right hand lane. with the larger size trucks, you have about 1 foot to the white line.

no big deal, i changed lanes and passed straddling both lanes, sort of wished the guy "good luck", he was in a BAAAD situation.


basically, you can't drive tired with a load like that - whether it's 26,000 pounds+ or 95,000 pounds. that would be my concern, not the weight, but the attitude of the driver. they're up in the "Wide Load" category, even if the load's not over-weight.

chad
12th December 2011, 01:10 PM
okay, so you have all convinced me to be paranoid. especially gundriller.

hoarder
12th December 2011, 01:25 PM
If a bridge is rated at say, 60,000 pounds, I wonder if that means at any conditions. If you're old enough to remember throw rugs on waxed wood floors (before the days of polyurethane finishes), you probably remember what happens when you stop walking...you and the carpet keep going. I've noticed rural roads that were wrinkled where big trucks approached a stop sign, they pulled some blacktop along with them. If you get out and examine blacktop roads where there's a sharp bend in the road, you can usually see cracks where the road is being slung outboard by the force of traction of trucks making the bend.

So if a bridge is rated for a truck crossing it, you can understand that a truck slamming on his brakes on that bridge puts 3 times as much strain on it.

Dogman
12th December 2011, 01:31 PM
i had a pucker factor experience when i pulled an overweight truck into a Cal Highway Patrol weigh station.

the law is, you can use a regular license for up to 26,000 pounds.

i was a few thousand pounds overweight.

for that you're supposed to have a Class A license, i was informed.

i won't say the number of laws i broke, i don't want to jinx my good luck - they let me off with a warning.


one of the many truckers i talked to was carrying 80,000 pounds. it sort of pissed me off because he got 7 miles per gallon - and that's what i got with 1/3 the weight !

i could tell he took his work very seriously.

the opportunity to do a huge amount of damage in a short amount of time is there every second with a vehicle that size.

i came around one corner driving in the dark, there was a truck with a trailer stopped on the right - all the way onto the shoulder, but 2 feet into the right hand lane. with the larger size trucks, you have about 1 foot to the white line.

no big deal, i changed lanes and passed straddling both lanes, sort of wished the guy "good luck", he was in a BAAAD situation.


basically, you can't drive tired with a load like that - whether it's 26,000 pounds+ or 95,000 pounds. that would be my concern, not the weight, but the attitude of the driver. they're up in the "Wide Load" category, even if the load's not over-weight.

Was that you that was going to move the machine shop, from your passed away friends house to yours? If you posted about it, I may have missed the end of the story!

Dogman
12th December 2011, 01:44 PM
If a bridge is rated at say, 60,000 pounds, I wonder if that means at any conditions. If you're old enough to remember throw rugs on waxed wood floors (before the days of polyurethane finishes), you probably remember what happens when you stop walking...you and the carpet keep going. I've noticed rural roads that were wrinkled where big trucks approached a stop sign, they pulled some blacktop along with them. If you get out and examine blacktop roads where there's a sharp bend in the road, you can usually see cracks where the road is being slung outboard by the force of traction of trucks making the bend.

So if a bridge is rated for a truck crossing it, you can understand that a truck slamming on his brakes on that bridge puts 3 times as much strain on it.Horder the joys of


Washboard roads, that will shake your eyeballs and fillings out of your head, plus damage too the suspension of your vehicle.

In this area, being old oil patch, there are hilly roads and curves on them that have ruts that you can take your hands off the steering wheel at speed, 50-60 mph, and the vehicle will drive itself through and out of them. I have done just that with visitors that I was showing them the area. 1821

If you do not know they are there, they will make you shit your pants and make you fight the steering wheel, instead of letting the ruts guide you.

Very heavy overloaded drill rigs and tanker trucks are responsible for that. Every few years they try to fix them, no joy! Some of those ruts have been in place at least for the last 50-60 years.

Glass
12th December 2011, 03:14 PM
I think someone posted about the ice road truckers and there was some info about the carrying weight of a moving truck compared to a stationary one. IIRC there was about 20,000 pounds difference in load, moving vs stationary.

Dogman
12th December 2011, 03:19 PM
I think someone posted about the ice road truckers and there was some info about the carrying weight of a moving truck compared to a stationary one. IIRC there was about 20,000 pounds difference in load, moving vs stationary.
The pressure point is moving and is not static, so the stress is not in one place for long, Sort of distributing the load over a wider area, instead of one spot.

Tumbleweed
12th December 2011, 04:54 PM
When I drove truck you could be 12000 lbs on the steers, 34000 on the drives, 34000 on the tandems on the trailer for a total of 80,000. Pulling two trailers with three axles in the middle you could be 43,500 on them with a gross weight of 116,000. the weight has to be distributed over maybe a 115 feet which is the length of the truck and trailers I'd pull.

I drove over the road for a year and a half all over the country. In the mornings it would be wall to wall trucks going into the cities. People will starve in a hurry if the trucks ever stop rolling into the cities.

palani
12th December 2011, 05:04 PM
People will starve in a hurry if the trucks ever stop rolling into the cities.

No Twinkies or Hostess Ho-Ho's today?

gunDriller
13th December 2011, 06:16 AM
Was that you that was going to move the machine shop, from your passed away friends house to yours? If you posted about it, I may have missed the end of the story!

well, Dogman, i didn't post the pics yet. i ended up doing it myself. the first affordable quote i got was from a trucker who didn't return phone calls at critical moments. then i found another, older guy - but he wanted the story to be that the tools belonged to him, if there was an accident - and i'm no good at lying - especially in a clutch situation.

3rd option - rent a truck - that's what i did. i'm working on the equipment dollies now - everything is unloaded & tarped & (knock on wood) protected.

vacuum
13th December 2011, 06:35 AM
I believe civil engineering uses a safety factor of 10, meaning the stuff they build should be able to hold 10x the weight before failing, according to calculations. So I'd think that most danger is not the load on the beams and columns, but rather, surface wear type issues. I'm not sure if the 10x is really true though...I've never designed a bridge.

TomD
13th December 2011, 06:58 AM
I've done some structural design but not bridges and especially not bridges with Federal specifications. Given that I'm pretty sure (actually very sure) that the probably of structure failure due to increased allowable truck weight is right at zilch.zero. Traffic density is a larger factor in total load than the weight of individual vehicles. Vacuum got it right, mostly the increased weight will mostly tear up the road surface.

Neuro
13th December 2011, 07:04 AM
I believe civil engineering uses a safety factor of 10, meaning the stuff they build should be able to hold 10x the weight before failing, according to calculations. So I'd think that most danger is not the load on the beams and columns, but rather, surface wear type issues. I'm not sure if the 10x is really true though...I've never designed a bridge.
I have never constructed a bridge either, but I think you are in the right ballpark with your estimate, the problem is though that a bridge that is not maintained properly, may have 50% less tensile strength, then those 20% extra weight on the truck may start becoming a problem, if there is a flood undermining the fundaments, and the truck say have to break hard on the bridge...

Wasn't this one of the pledges of Obama's infrastructure investment proposals though to jump start the economy? To do maintainance work on bridges and roads, a few years back? Has people seen any increase in maintenance work, the last couple of years, or did the money go to Israeli surveillance and security technology only?

palani
13th December 2011, 07:37 AM
Hearts and minds takes back seat to WMDs and military toyz.

po boy
13th December 2011, 08:30 AM
Nero there's been lot's of construction on the interstate here not rebuilding though mostly new.