Why do sidewalks have blocks, instead of being solid?
In: 205
The ground underneath concrete tends to shift and move depending on the weather.
Having separate tiles allows them to move, expanding and contracting. Without that the tiles would crack and break very quickly resulting in an uneven and dangerous surface.
If a tile breaks it can also be replaced without needing to replace the entire side walk.
Roads suffer from this as well, but the underlay is better prepared so that this effect isn’t as bad. They don’t often do that for sidewalks because it costs a lot more.
Bunch of reasons.
Ease. Sidewalks are usually too small for large cement or asphalt trucks to drive across and work on. Stones can be laid no matter the size of the path.
Practicality. Water, power and gas lines usually run beneath sidewalks. If there’s an issue or they need access for some reason, it’s easier and cheaper to take out stones than it is to break apart asphalt or cement and then redo it.
Aesthetic. Many people prefer the look of stones to a single solid slab.
Sidewalks also don’t need the durability of roads, since there are no cars driving over them. At least not as much or as fast.
Sidewalks flex, get pushed around by trees, crack, and need to be replaced. If the sidewalk was solid for the whole city block and it got a bad crack halfway down, you’d have to either replace the entire thing at once or cut into the existing concrete to replace a smaller section, like a “block.” But since they already do blocks, they can only replace the damaged or heaved parts of the sidewalk.
They replaced our sidewalk last month and they only did the damaged bits. They’re not planning to revisit the sidewalk on our street for 15 years. The ones that are fine, flat, and not cracked or damaged they didn’t replace, saving us money.
In my area the sidewalk is about 300-400 feet long and was all replaced a couple of years ago. They put groves in it about every 4-6 feet so that if it settles or a tree root or freezing temperature pushed it up it will crack along the grooves made in it. Also if a piece needs to be removed to do other work underground like water, gas, electrical they can easily cut at the grooves made when first pouring it without doing the whole block.
Concrete roads usually have the same grooves but are usually 10-20 ft apart.
Concrete sometimes breaks when being cut and this way you only replace 6-10 feet for repairs instead of the whole side of the street.
Easier construction, and then the squares can expand and contract with the ambient temperature without breaking as much.