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Dense foot traffic weighs more than even dense vehicle traffic. That is why the Brooklyn Bridge swayed during the blackout evacuation.

Think of it like this. Your body mass is denser and thus weighs more than a vehicle.

Consider this, a car has a footprint of around 45-50 square feet while a person has a footprint of around one square foot and weighs 150 pounds.

The weight of people Walking in a 50 square foot area is 7500 pounds much heaver than the average vehicle.

Dense foot traffic weighs more than even dense vehicle traffic. That is why the Brooklyn Bridge swayed during the blackout evacuation.

We are not talking dense foot traffic. We are talking a few groups at a time that were not allowed to leave.

You are full of it.

Oh, and fifty square feet is a five by ten space. You are conjecturing that on a large bridge, fifty people or so in a scattered movement would pack themselves into a five by ten space, or about the floor space of two elevators.

I don't think so. More bullcrap from you.

Consider this, a car has a footprint of around 45-50 square feet while a person has a footprint of around one square foot and weighs 150 pounds.

Huh? 45-50 sq ft? 10-12 sq ft per tire? I'd say you're off by a factor of five, at least.

OTOH, I could see how walking would be heavier than the same weight on a vehicle in part because the body is falling with each step, not rolling on a tire.

"Your body mass is denser and thus weighs more than a vehicle."

Oh, my. How funny. Let's look at this. Let's take a school bus for example, fully laden. Maybe 50 souls on board. Pretty closely packed, I'd guess. You're trying to tell me that 50 people walking across the bridge somehow weighs more than the same 50 people on the bus. Silliness.

Walking, they'd be no more closely spaced than they were on the bus.

Another example. I drove a 24' box truck across many small bridges when I moved. The entire truck was 30' long and 8' wide. It's weight, measured by several state truck scales, was 17,600 lb. Now, take a 30'x8' line of people. Let's see, if they were toe to toe and shoulder to shoulder, that would be a column 30 people long and 4 wide. 120 people, weighing an average of, say, 160 lb. each. Let's do the math: That would add up to 19,200 lb. Of course, they couldn't walk if they were that close together, so let's make it 15 long and 4 wide. That's 9600 lb.

If the truck or bus can cross the bridge, there's no problem with the folks walking across the bridge. Feh!

Dense foot traffic weighs more than even dense vehicle traffic. That is why the Brooklyn Bridge swayed during the blackout evacuation.
Think of it like this. Your body mass is denser and thus weighs more than a vehicle.
Consider this, a car has a footprint of around 45-50 square feet while a person has a footprint of around one square foot and weighs 150 pounds.

The weight of people Walking in a 50 square foot area is 7500 pounds much heaver than the average vehicle.

You're full of it. Where did you get your engineering degree?

Have you ever heard of the Chesapeake Bay Bridge Walk? One day a year, tens of thousands of people walk across the bridge and are shuttled back on the other span.

Forty to 60 thousand people show up every year, to walk the 4.3 mile bridge, part of which is suspension. See the photos at:

http://www.roadstothefuture.com/Chesa_Bay_Bridge_Walk.html

Don't they also have a bridge walk on the Golden Gate bridge?

Per Person - "close" packing shoulder to shoulder, front to back under normal crowd conditions:
Width - "depth" - sq ft - avg wt - lbs / sqft
2.5 ft - 1.5 ft - 3.75 sqft - 175 lbs - 46.67 lbs/sqft

"Average" automobile - Ford Taurus Station Wagon
Width - "length" - sq ft - avg wt - lbs / sqft
6 ft - 14 ft - 84 sqft - 4894 GVW - 58.3 lbs/sqft

This is with the car "full" of course.

And furthermore, the actual deck-load at each tire is much higher, of course...