108-year-old core sample from Indianapolis Motor Speedway track - photo

[Jon]

108-year-old core sample from Indianapolis Motor Speedway track, including the original bricks from 1909.



Previously:
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Slow motion dragster GIF
steam locomotive drag racing
NHRA Funny Car engine explosion

[owen moore]

I would love to have that in my man cave.

[Ralphxyz]

It is upside down? The brick is on the bottom? It is about 5" tall?

Certainly is interesting.

Ralph

[Frank S]

Notice the crack in the top layer of the core sample.Core samples of craks are often taken to determine the origins or reasons for cracking this allows engineers to analyze a solution to prevent them from occurring again . I can see where a deep under laying crack dating all the way back to the brick would have been the culprit, what would have been even better would be if the core sample had included the first attempt at creating the road way surface which was gravel oil and a tar like substance, plus a couple more feet of strata below that. Then another core sample from an area where no visible cracking could be located using an ultra sounding seismic device would show where compaction may not have been completely even. The over 3 million bricks were not added until late in 1909 the first actual 500 mile race wasn't until 1911

[Jon]

In the topmost, newest layer, there are no visible embedded rocks. Why? Safety issue? Technological advancement in paving? Are all of the layers in between the topmost layer and the lower bricks identical?

[Frank S]

Jon looking at a close up view of the top layer it would appear the formulation of the surfacing material has indeed undergone technical upgrading. That plus you can see smaller bits of aggregate mostly discolored indicating the possibility of recycled materials were involved as well. I also detect several small voids in the layer which means to me either high or low heat at time of application that plus possibly not enough compaction rolling. If the heat was too high the voids could have been formed by out gassing if the heat was too low I would suspect trapped air pockets due to not being rolled enough times.
In any case these voids can lead to moisture permeating down into the layer which would freeze in winter, and we all know what that can lead to

[Ralphxyz]

The top layer pictured is actually the first layer in construction or is this built on top of the bricks?

Supposedly this a core sample taken in 1909.

Ralph

[Frank S]

Ralph the Indianapolis speedway got the name the brick yard because it was paved with 3.2 million 10 lb bricks after it was first constructed. the Idea and inital construction dates back to 1906 the first races were ran in I think June of 1909 it wasn't until 1911 when the first 500 mile race was ran it wa won by a Marmon car the predecessor to the Marmon trucks I don't know when it was finally paved over with asphalt.
but yes all of the layers shown in the picture are on top of the bricks

[Ralphxyz]

Thanks Frank, it's interesting the major crack that they centered on when they took the sample looks like it might have started at the very first, top pictured, layer.

Ralph

[Frank S]

Thanks Frank, it's interesting the major crack that they centered on when they took the sample looks like it might have started at the very first, top pictured, layer.

Ralph

Ralph, core samples can only create a snapshot of things below. Cracks in road surfaces rarely ever start from the top without some underlying fault which lends to their being.
If you note in the picture that Jon first posted you can see a crack down below in the brick an d one at the top in the top layer, but there appears that there is no crack in ht every middle layer. However what we can not see is the length of the crack. Since paving materials other than concrete or mortared together brick retain some semblance of elasticity just not consistently some areas will stretch while others will separate. also cracks rarely ever run true linear in a straight line so we may not be able to see the crack due to it being either more towards the center of the core sample or even possibly to the outside of the sample