Ray, they are called "starting rods", not reinforcing bar. A piece of rebar is stuck in newly poured concrete and left sticking out as evidence of the correct steel being installed in the concrete. The inspector comes around and sees the steel and is reassured that all is well.
The process is supposed to be that the inspector checks the steel before the concrete is poured, but things are often done in a hurry in the construction industry and it's all about the profits. Quality control is not as of great concern to the contractor as their profits. I wonder if inspectors in China are ever offered bribes. Yiwu doesn't read my stupid rants [do you Yiwu?] but maybe Jay could say whether he's heard of bribery in China.
If a building falls down in 20 years in an earthquake, well, bad luck. Design engineers use factors of safety, making the building stronger than necessary, so the contractor will probably get away with it anyway.
Our concrete professor in the early 1970s thought that there could be a problem with buildings in Wellington, a major earthquake region, in the event of a decent earthquake as he didn't think the curing process was correctly handled in the rush to get the buildings up quickly. Concrete needs to stay wet to strengthen and the process takes weeks, not days. Membranes are sprayed on to maintain moisture.
28 day strength was the arbiter of whether the concrete was properly manufactured.
No doubt design, construction, quality control and management techniques have moved on a lot since my day. But from watching buildings being built in China, they seem to be using the techniques we used 30 years ago. I expect the profit motive and indifference to other people means some buildings aren't as good as they look from the outside.
Some roads leading north from Beijing are nice big highways, but they are already ruined by heavy trucks crushing grooves in them. Building failure shows up under load, which happens in earthquakes, high winds or other severe and infrequent conditions. Road failure shows up when the vehicles get on them.
I wonder if Chinese buildings are built with starter rods instead of reinforced bars, reinforcing bars, rebar, or reinforcing steel.
My experience of Chinese selling things was that honesty was irrelevant. It was to the extent that I am not sure that there is such a thing as an honest person in China. I'm sure there is, but I'm not sure I met them. Chinese culture is grab, lie and take. No wonder they want to attack Taiwan and somehow get their greedy clutches on Hong Kong's loot. They don't have Libertarian concepts as their impetus.
They should be honest like King George II who only wants to liberate Iraq, and provide excellent services by Halliburton, bringing the joy of democracy and freedom to Iraqis and Afghanistan. It's nothing to do with oil or revenge against Saddam.
Though it does puzzle me that he doesn't want a United Nations reformation with democratic processes running the UN in a nice, new, all-inclusive constitution for managing Earth's commons. He's in favour of democracy, but only as long as the PNAC is in charge. He's sounding very much like the King of England against whom the Declaration of Independence was written.
Mqurice |
