Not sure where to post this. I was watching one of those blow down shows last night, they were toppling 4 large concrete nuclear cooling towers in England. They are massive structures, several hundred meters high. Just really huge, and appear to be solid concrete and steel. What really shocked me is they actually don't sit on the ground. They rest on a set of legs may be 10 or 15 feet off the ground, so that air can get in from underneath (for the cooling) The legs look so spindly, I could hardly believe that is all that holds them up. I wanted to know what something like that would weigh, and how on earth those legs could support it in wind, earthquakes, and the like.
Where did you see this? was it on TV or the Web? How were they tearing them down? Sounds interesting! John
Honestly, i think the show was called blow down. It was one of those shows on tv where they use explosives to bring down large structures. It was interesting. I never knew inside those towers there is not much of anything. They act like a big chimney open on the bottom. By the sounds of it, they would run a hot water loop through open cold water tanks in the bottom of the tower. The cold water boils away, and the updraft created by the tower causes the steam to rush up, and air to rush in at the bottom. Water to water cooling like this produces a massive steam cloud out the top of the tower. Alternately, sometimes they use water to air heat exchangers in the base of the tower, and the inrushing air flows across cooling fins (like a car radiator) and then rushes out the top of the tower. Used in this way, the hot air rises with no obvious visible signs. But like i said, there was maybe 60 or 80 columns extending out of footings that appeared to be no larger than 3x5' . the columns were maybe 12" concrete and rebar. It compared to supporting a filled 5 gallon bucket with toothpicks around the perimeter of the base. It seemed really weird. At first i thought the maybe they removed some of the support structure. But they explained the bottom was completely open to allow huge volumes of air in to cool and rise up the tower. So i figure the way it was shown is the way it has always been. Here is the web site. http://natgeotv.com/asia/blowdown/galleries/nuclear-explosion
Just the same structure with Steam cooling towers of the Mochovce nuclear power plant are seen on June 11, 2008 in southern Slovakia. Enel Spa Slovak unit signed a contract with suppliers for the construction of two additional reactors at its Mochovce nuclear plant. Enel's Slovenske Elektrarne plans to invest 2.7 billion Euros.
Most power station cooling towers in the UK were like that and always have been to my knowledge. As you point out the idea is to create a giant chimney so that a natural draught occurs that pulls the heat from the water, no fans involved at all. I can't honestly say I've ever heard of one falling down unless it was being demolished. These days with space restrictions cooling towers tend to be much smaller and of the forced fan variety.
they're pretty damn strong but usually only around 6" Thick toward the top.
Just a hollow tube with a sprinkler system......
hey guys, the cooling towers you speak of are natural draft hyperbolic cooling tower. they are a little more costly to build, but offer cheap running costs due to the lack of need for draft fans. I believe you would lots in England due to the high humidity around there as they work well in the that environment.