Purpose of kerbs

[FW17]

The most annoying thing I recall while using sim tracks in reverse is the fact that there are no kerbs in the turn exits. You have to be careful not to touch the grass with the wheels. Laptimes would be better with the appropiate kerbs.

Always wanted to know the purpose of a kerb, what is it for?

[Mandrake]

A curb (kerb?) is an extension to the actual track, making it wider. Wider track means higher cornering speeds. This is for flat curbs only though. Also when there are curbs in the corner's or chicane's apex, you effectively decrease the radius of the corner as you can cut the curb.

That Nordschleifen video shows exactly that the track is not built for reverse driving. Also the outposts for the marshalls are opened up if you go reversed, while they are fully covered in normal direction. curbs wise the Nordschleife would be drivable in reversed mode

[Roland Ehnström]

Originally (I'm talking 50-60 years ago) kerbs were added to the tracks in certain corners to stop the drivers from taking short-cuts over the grass (like we see in Rallying) and kicking up dirt onto the track. (Interestingly, in the famous Karusell corners at Nürburgring Nordschleife, the opposite solution was found: Drivers kept using the dirt ditch on the inside as a banking, so the organizers decided to put concrete there and make the ditch part of the actual track.)

These days, I have a feeling many kerbs are way too wide and shallow, which defeats the purpose.

[Mandrake]

Just figured out that kerb is BE and curb is AE. Why the hell did I use the American word until now?

I agree to Roland, kerbs can be (and will most likely have been) used to also stop drivers from cutting. The very kerbs on the Nordschleife are indeed such kerbs.

Today though, they are much more extentions to the track, as I've meantioned in my previous post.

[bot6]

The purpose of kerbs is to make Russians fly.

[Tim.Wright]

They were probably put there originally to protect the edge of the asphalt from breaking up as cars bounce across them.

Its cheaper to replace a concrete kerb, than repair the asphalt.

Tim

[Giblet]

The purpose of kerbs is to make Russians fly.

That was a rain gutter he hit IIRC. I suspect he will be more aware of them in the future.

[Belatti]

I would like to read what Ciro (F1T civil and circuit engineer ) has to tell us about kerbs design. Not only about wide but also about height and angle. This is very important and the first thing it comes to mind is Barrichello at Imola 1994.

That pic of Petrov taking off was not in a kerb but in the grass.

What I would do with kerbs profile is to make 2 slopes so that, up to the middle of the kerb it contains you and after the middle it spits you out (inverse slope) of the track. That way you keep then tricky for drivers

[Shrieker]

In April of 2005 I was able to walk Istanbul Park in it's final stages of construction. I saw that the kerbs were covering rain gutters. So I assumed that that was the real purpose of the kerbs. But probably not all the kerbs were covering rain gutters (I didn't pay that much attention or can't remember tbh).

[Pandamasque]

This is interesting. From what I can see at most modern circuits, the only purpose of curbs is to keep cars away from the dirt and hence keep the asphalt clean even when some cars run wide and cut the corner slightly.

I hope Ciro clarifies this.

A curb (kerb?) is an extension to the actual track, making it wider. Wider track means higher cornering speeds............

... For the avoidance of doubt:
the white lines defining the track edges are considered to be part of the track but the kerbs are not.

[Caito]

Since in a racing car you are normally very low and can't see a thing, aren't kerbs to know when you are in the limit of the track?

[HampusA]

My guess is some kerbs actually helps the car rotate in to the corner by slowing down the inside pair of wheels a tiny amount.

[Belatti]

Since in a racing car you are normally very low and can't see a thing, aren't kerbs to know when you are in the limit of the track?

No matter how low are you, if you can see the track 10 meters in front of you, then its OK.

[flattyre]

Since in a racing car you are normally very low and can't see a thing, aren't kerbs to know when you are in the limit of the track?

I'm no civil engineer or track designer, but I think that this might be correct. On the motorways here in the UK, the white lines at the side of the road have small bumps in them that act similarly to a 'rumble strip' by making a loud noise and vibrating the car's wheels. This tells the driver that he's too close to the edge of the road. Maybe that is the idea behind the modern style of motorsport kerbs - simply to warn a driver that he is close to the edge? I wouldn't be surprised, seeing as you only see kerbs on the entry, apex and exit of corners - all places where the car will be close to the edge of the track.

Whatever their purpose, though, I think that kerbs are one of the more entertaining parts of racing - seeing or feeling a car go up on two wheels over a high speed kerb is fantastic

[Caito]

Since in a racing car you are normally very low and can't see a thing, aren't kerbs to know when you are in the limit of the track?

No matter how low are you, if you can see the track 10 meters in front of you, then its OK.

As long as you are in a straight line, it is. If the road is changing(i.e. you are ina curve) you can't certainly know how close to the limit of the track if you can't see. You can be pretty damn close with practice.

Pilots tend to use the whole track for obvious reaons, and they regularly miss the track. If that's the reason for kerb, I don't know for sure but I'd place my bet on that.

If not they'd be plain, they make you rumble, as flattyre said, to warn the driver.