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Comment by jonathankoren | Hacker News Reader

Yeah. China is full of make-work programs. It's obvious.

For example, every Chinese city has sidewalks made, not of poured concrete, but rather 30 cm x 30 cm ceramic tiles. Due to historic city planning, the Chinese tend to park their cars on the sidewalks, which inevitably breaks the tiles, thus causing regular replacement. These tiles are laid not by some sort of brick laying machine, but rather by hand.

The sidewalk by my house was poured in 1968. I know that, because there's a date stamped in it. A couple of blocks over there's a sidewalk that someone scrawled graffiti into. "Elton John 75". There's literally nothing wrong with either of these sidewalks. They're not cracked, nor buckled.

China doesn't need to replace every sidewalk every two or three years, but they choose to.

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Truthfully, based on the state of our sidewalks in the richest cities of the US like NYC, SF, Chicago, and LA— we need to be replacing them maybe not every two or three years, but at least every 5. Right now it seems like 20, if we’re lucky. Meanwhile most towns and newer parts of smaller, less affluent cities, or even wealthier suburbs don’t even _have_ sidewalks.

I think it’s ultimately part of our philosophy toward the built environment that “Europe is built with screws, the US is built with nails”— we build something that gets the job done at the time it’s built, then never come back to it. Maybe that allowed us to build fast, but now the bigger issue is maintenance of what we already have.

screws - axial load

nails - less axial load with shear stress

nails are made of a more pliable metal, whereas screws are more brittle. the real "long-term" fastener, in my opinion, would be bolts; but I don't see anyone using those to frame a house.

Timber framed houses often use through bolts, as do decks. Modern houses have bolts in them but they’re hidden

just a counter-point, if it is at all; I grew up in SoCal with poured sidewalks around the entire area. Nearly every single one of them was destroyed by nearby trees or shrubbery extending their roots under the thing and cracked it up into a million pedestrian-tripping pieces.

These sidewalks were from the 60s and 70s too -- thing is that they cracked 20-30 years ago and no one ever bothered to replace. The home owners i've spoken to that wish they could were confronted with the aspect of being forced to pay for their entire street lest they wish to pull permits to repair their small section.

So you have this new problem with a liability tug-of-war between well-wishing civillians against the cost-saving municipalities, and to be clear this was more than one single municipality, i've seen it across SoCal.

So, what i'm trying to get across is that there is a middle ground between 'needless replacement for the sake of generating work' and 'neglect', and neither China or the US has seemed to pin that middle down yet : but that needless replacement regime sure sounds nice as a pedestrian that just wants to use the goddamn sidewalk. I've seen busy-work before, that just doesn't strike me as that.

Here in the netherlands we have a tremendous amount of sidewalks per capita and they are 99.99% tiled. Some of the sidewalks are over 50 years old and stil in good shape. There are many benefits of tiled sidewalks. Its pretty easy to put cables underneath. Happens every few years (internet, electricity). You also dont need fancy equipment to make them. Or repair them.

Dutch tiled sidewalks are different from what I have seen in China. They embed thick tiles, hardened bricks nowadays, in sand. Chinese make concrete sidewalks topped with thinner tiles. Nice when it rains some tiles work like mud pumps spraying your feet.

BTW I have no statistics on Chinese sidewalk maintenance, but when I lived there development was so fast that a sidewalk would have to be broken up every 2, 3 years anyway for new cables, pipes or whatever. I always wondered why they didn't use the tile plus sand system, as this involved always in noisy and dusty concrete hammering.

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