3 ms·

The beginning of the article sounds so modernist mid-20 century, I couldn't stand that. Old roads that formed on old paths are much more stable because people

The beginning of the article sounds so modernist mid-20 century, I couldn't stand that. Old roads that formed on old paths are much more stable because people went where the area was dry, and then dirt roads were stable and didn't move down or cause rain erosion. The generalizing phrase, that terrain is just an obstacle that should be plowed through, is laughable. People lived very well without retaining walls and without such huge excavations, until transport engineers decided to please cars, and not slow them down, or not make them go too steeply. Same for the sentence about buildings. There are plenty places where slopes are taken adavtage of. In Stockholm, there are some houses that have +2 storeys on one side, and entrances to 3 storeys from different sides. In my town, a mall built in 1960s has 2 storeys, the top one can be entered without steps at all. In Finland, they used sloped ground to build stadiums, and even to make basements with windows. People like parks with slopes, children like to ride sleighs in winter on them. The most stupid thing you can do near housing is a flat surface and a concrete retaining wall. That generates more problems than benefits: the wall may float, it may create new concentraded areas of water running on the surface, and mini-waterfalls in rains. This never happens with natural slopes, because with grass they're very stable at 3-10 degrees, unless you concentrate water runoff on them. Finally, the place becomes completely uncomfortable to stay at. It's pretty normal to lay down on a grass on a slope. But unthinkable if there's a retaining wall above you. Unfortunately, nowadays I see the architects and clients prefer not to think and adapt to terrain, but just bulldoze the ground. Otherwise, yes, there are engineering solutions to making retaining walls and making them stable.

creato 5y ago
There are more people now, and more people means pushing into more marginal areas. And, I'm sure people built roads that sank and eroded in the past too, they just aren't around any more. Personally, I care a lot more about hills when I'm riding a bike or walking. When I'm driving a car, hills don't matter. At the same time, building on slopes can be problematic. It depends on the local geology whether it is possible to do that or not. FWIW, I'm a bit tired of "cranky old guy thinks everyone else is an idiot" posts on HN.
- mega_dingus 5y ago
  | And, I'm sure people built roads that sank and eroded in the past too, they just aren't around any more. I believe that's called "survivorship bias"
- culebron21 5y ago
  Ok, I may have put it in annoying tone, will try better next time. As for buildings on slopes. Swedes and Finns enjoy rocky ground, to which bulidings stick perfectly, and they make all the nice things I mentioned. Here's an example: a mall & offices complex, the elevation difference is 5 m (15 ft): https://www.google.com/maps/@60.1687254,24.9389851,295m/data=!3m1!1e3 https://www.google.com/maps/@60.1687254,24.9389851,295m/data... If there's rock under the ground, you bore and put the building on pillars. It won't matter if the surface around the buliding is flat or not. If you have to build on a sedimentary (sandy) slope then a retaining wall won't fix this at all. You'll need many long piles to hold it to the ground by friction. Retaining wall -- no matter which end of the constuction site -- would have to be a huge and heavy structure to hold to the ground, otherwise it'll be slipping couple of cm/inches per year, which is enough to cause problems. Even if you level the site on a slope and sedimentary ground, a building will still need long frictional piles to be stable.
mitchdoogle 5y ago
A slope at a park is nice for the occasional sled, but slopes aren't that great when you're trying to play organized sports, or if you want to set up temporary structures or host events at your park (kind of difficult to set up a tent at an angle). Other than natural areas, such as national parks or forests, these are the primary reasons I have been to parks in recent years.
- culebron21 5y ago
  You're right that playgrounds can't be steeply sloped. But, first, many playgrounds are sloped up to 3%, people just don't notice that, and put tents on 3-5% slope without issues. (But if you mean tent for sleeping, I slept on 10% slope, without problems.) Secondly, for playgrounds, you can put the pitch along level lines, level only the pitch itself and leave a steeper slope next to it to serve as a grandstand. Example from Finland: https://goo.gl/maps/CssidLvnTYCeZ6Qx8 https://goo.gl/maps/CssidLvnTYCeZ6Qx8 Thirdly, a playground still does not require the entire lot to be leveled, which I see nowadays a lot. Earlier architects, if they wanted to build just a copy&paste standard project (rather than design something new with entries on different levels), they'd just put buildings and playgrounds along the level lines, and minimize levelling works. The lot would have 2-3 small slopes of 15-20% with grass on them between buildings or playgrounds. Nowadays, with digging machinery available, even if the same can be done, clients (mostly public agencies) order to level everything and build retaining walls at both ends. My point is there's a plenty of ways to work around slopes in parks and land lots.

creato 5y ago

There are more people now, and more people means pushing into more marginal areas. And, I'm sure people built roads that sank and eroded in the past too, they just aren't around any more. Personally, I care a lot more about hills when I'm riding a bike or walking. When I'm driving a car, hills don't matter. At the same time, building on slopes can be problematic. It depends on the local geology whether it is possible to do that or not. FWIW, I'm a bit tired of "cranky old guy thinks everyone else is an idiot" posts on HN.

mega_dingus 5y ago
| And, I'm sure people built roads that sank and eroded in the past too, they just aren't around any more. I believe that's called "survivorship bias"
culebron21 5y ago
Ok, I may have put it in annoying tone, will try better next time. As for buildings on slopes. Swedes and Finns enjoy rocky ground, to which bulidings stick perfectly, and they make all the nice things I mentioned. Here's an example: a mall & offices complex, the elevation difference is 5 m (15 ft): https://www.google.com/maps/@60.1687254,24.9389851,295m/data=!3m1!1e3 https://www.google.com/maps/@60.1687254,24.9389851,295m/data... If there's rock under the ground, you bore and put the building on pillars. It won't matter if the surface around the buliding is flat or not. If you have to build on a sedimentary (sandy) slope then a retaining wall won't fix this at all. You'll need many long piles to hold it to the ground by friction. Retaining wall -- no matter which end of the constuction site -- would have to be a huge and heavy structure to hold to the ground, otherwise it'll be slipping couple of cm/inches per year, which is enough to cause problems. Even if you level the site on a slope and sedimentary ground, a building will still need long frictional piles to be stable.

mitchdoogle 5y ago

A slope at a park is nice for the occasional sled, but slopes aren't that great when you're trying to play organized sports, or if you want to set up temporary structures or host events at your park (kind of difficult to set up a tent at an angle). Other than natural areas, such as national parks or forests, these are the primary reasons I have been to parks in recent years.

culebron21 5y ago
You're right that playgrounds can't be steeply sloped. But, first, many playgrounds are sloped up to 3%, people just don't notice that, and put tents on 3-5% slope without issues. (But if you mean tent for sleeping, I slept on 10% slope, without problems.) Secondly, for playgrounds, you can put the pitch along level lines, level only the pitch itself and leave a steeper slope next to it to serve as a grandstand. Example from Finland: https://goo.gl/maps/CssidLvnTYCeZ6Qx8 https://goo.gl/maps/CssidLvnTYCeZ6Qx8 Thirdly, a playground still does not require the entire lot to be leveled, which I see nowadays a lot. Earlier architects, if they wanted to build just a copy&paste standard project (rather than design something new with entries on different levels), they'd just put buildings and playgrounds along the level lines, and minimize levelling works. The lot would have 2-3 small slopes of 15-20% with grass on them between buildings or playgrounds. Nowadays, with digging machinery available, even if the same can be done, clients (mostly public agencies) order to level everything and build retaining walls at both ends. My point is there's a plenty of ways to work around slopes in parks and land lots.