Road surfaces

[Cloozoe]

Living as I do in a third world country where the ruling class doesn't spend money on infrastructure maintenance, the vast majority of the riding I do is on ancient chip seal surfaces, riddled with potholes and frost heave and covered in debris.

That said, every once in a while I encounter an asphalt surface that was actually laid down this century (someone got bribed, I guess, or it was determined that the undeserving poor never drove that particular route and hence wouldn't benefit), and oh mama! What a treat! Aside from not being beaten up nor winding up unconscious in the road due to a crater not seen in time, I just fly.

Not sure how it would be done in a controlled manner, short of repaving half (width-wise) a lousy road and having a whole bunch of cyclists ride on each half and then collating the data, but anyone aware of any studies relating road surface to speed?

[mt2u77]

Living as I do in a third world country where the ruling class doesn't spend money on infrastructure maintenance, the vast majority of the riding I do is on ancient chip seal surfaces, riddled with potholes and frost heave and covered in debris.

So you live in Wisconsin too? We should ride some time. :)

(Sorry, can't help you much on your real question.)

[CMiller]

Find 2 flat roads, one messed up the other not, time a mile, and compare? haha

[MattTuck]

Are you an academic looking to study this? I was spit balling a similar question with a friend, and the best we came up with was the following.

Get a list of strava segments that were recently repaved. Look at the segment times for the month before and after the repaving, (or perhaps the 1 year prior month after the paving, if there is a seasonal effect) and study the mean, median, standard deviation, etc. If you can control for wind, even better.

If you have a big enough sample, (100 segments?) you could probably have a pretty good idea of how much faster new pavement is.

Anecdotally, we had a terrible road repaved a few years ago, and within a week of the new pavement, I think all the top 10 times in the leaderboard were post-paving.

[Cloozoe]

Are you an academic looking to study this? I was spit balling a similar question with a friend, and the best we came up with was the following.

Get a list of strava segments that were recently repaved. Look at the segment times for the month before and after the repaving, (or perhaps the 1 year prior month after the paving, if there is a seasonal effect) and study the mean, median, standard deviation, etc. If you can control for wind, even better.

If you have a big enough sample, (100 segments?) you could probably have a pretty good idea of how much faster new pavement is.

Anecdotally, we had a terrible road repaved a few years ago, and within a week of the new pavement, I think all the top 10 times in the leaderboard were post-paving.

Excellent thought. Not sure how one would find Strava segments that had recently been or were about to be repaved; post a request to users on various bicycle forums, perhaps?

I'm not at all surprised at your anecdotal report; my unscientific speculation based on my own riding is that the increase in speed is substantial, perhaps as much as 15%, assuming wind, slope, original avg. speed, etc. were controlled for, and, of course, depending on just how bad the "bad" road was and how good the "good" road was. But, again...excellent idea. Wouldn't have thought of it. Thanks.

mt2u77: be my very great pleasure to ride with you, but I'm in New Jersey.

[SlackMan]

I don't have any specialty in testing what you propose, but I wish some smart civil / highway engineers would. My hypothesis is that chip and seal surfaces not only make for less fun cycling rides, but they also reduce fuel mileage for autos and trucks and increase tire wear to such an extent that the auto and truck drivers would be better off financially in the long run paying higher taxes for smoother, higher quality road surfaces. I'm fully prepared to be wrong on this, but it's something that those who design and fund roads should know.

[palincss]

Honestly, the biggest problem with chip seal is too narrow tires at too much air pressure. And that is something entirely within your control.

[jemoryl]

Excellent thought. Not sure how one would find Strava segments that had recently been or were about to be repaved; post a request to users on various bicycle forums, perhaps?

I'm not at all surprised at your anecdotal report; my unscientific speculation based on my own riding is that the increase in speed is substantial, perhaps as much as 15%, assuming wind, slope, original avg. speed, etc. were controlled for, and, of course, depending on just how bad the "bad" road was and how good the "good" road was. But, again...excellent idea. Wouldn't have thought of it. Thanks.

mt2u77: be my very great pleasure to ride with you, but I'm in New Jersey.

Let me guess: Mercer County? I live in Essex and mostly ride here, Morris, Somerset and Hunterdon and have a number of routes based solely on having recently laid down blacktop. But several times every year I do some riding in the Princeton-Sourlands-Lambertville area and that is where they seem to love chipseal on the backroads. And it is a nasty kind of chipseal with little rough stones, not rolled out well (e.g. 'Pleasant' Valley Road near Lambertville).

But I really appreciate your third-world rant, because it feels like we are rapidly heading in that direction.

[cal_len1]

I think the best one I've seen is the Silca study from a while back, and although it might not answer your question, you might be able to read between the lines.

https://silca.cc/blogs/journal/part-4b-rolling-resistance-and-impedance

[thwart]

So you live in Wisconsin too? We should ride some time. :)

(Sorry, can't help you much on your real question.)

Ha! Beat me to it.