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Newark says it works great. See an update when Jason and Phil talk about it at the Roadway Management Conference this fall. Sorry about the background noise; we were competing with the construction of a lifeguard station. th-cam.com/video/7TtcPJLi8gM/w-d-xo.html

Let's hope. It was a long time in the making. I thought for sure they'd never even start construction. The planning went on for most of my career! I suppose patience paid off.

Usually, this is intended as a drainage layer. Water is the enemy of pavement and anything we can do to ensure that the underlying layers are well drained improves the chances for a durable pavement. PTB is usually a mix of stone (typically 57 Stone; think angular rock in the average range of 1/2 inch to 1 inch stone with very few fines) and either Portland cement or asphalt cement (asphaltic binder). The idea is to create a "popcorn" mix with lots of voids that water can flow through and away from the roadway, into underdrains, and so on.

Excellent question. See roadresource.org under their treatment toolbox for more, but a common cutoff uses linear feet of crack per length of pavement or per square foot of pavement and cutoffs vary as to what constitutes "a lot". For example, more than about 100'-150' of crack per 100' of road length starts to be considered extensive and if a lot of those cracks are more severe, you may have let it go too far. Another consideration is width of crack. Some go as narrow as 1/8", but commonly you wouldn't mess with cracks less than 1/4" (after they are blown out) and a typical upper limit is about 1", maybe 1-1/4". Beyond that, it can be difficult to get good adhesion, even with premium materials and great surface prep. When the crack density or amount of cracking is too high (and some use a number higher than 100-150; it is really a good cost benefit analysis exercise), you are probably headed for the mill and overlay area, but if other distresses like potholes and such aren't evident, you can buy some time. If your cracks are mostly narrow, consider sealing the wider ones and then perhaps buying some time with a slurry seal or fog seal. If your problem is wider cracks, consider mastic.

Usually, if the crack density is too high, it is random cracking. Environmental cracks (those evenly spaced transverse ones) aren't usually the problem. Longitudinal cracks marking the paving passes can be manageable if the construction of the joint was good. If those begin to widen considerably or deteriorate locally, mastic may be a solution for a while. But if random cracks begin to proliferate, it is usually inevitable that alligator cracking is not far behind and there may even be some structural issues that need addressed. More often than not, this usually points to a mill and overlay, possibly with some full depth repairs. Full depth reclamation can be an alternative if there is a lot of subbase failure, usually coupled with cement or other stabilizer. If the cracks are dense but very narrow, some will buy some time with a slurry seal, but that needs to be looked at very carefully to make sure you're not throwing good money after bad. Moral of the story is seal cracks early and often; cheapest treatment you can use.

Quick answer is we don't have that information. I would guess in the arena of 20 tons, but it could be more on the order of 30, based on the weight of fairly pedestrian pieces like box culvert sections.

You bet! Hope you enjoyed it.

It is a close cousin to microsurfacing. You can get pretty wonky debating the differences between the various slurry types and microsurfacing is a type of slurry seal, but one of the primary differences is the polymer emulsion used. Microsurfacing is a beefier version of what you see here.

Well, we were just the videographers in this instance, but we'll pass on the compliment when we see them!

I don't know of any off hand. You are typically powering that with a 20 pound propane tank and you can get some good BTUs from that and it will do the trick. You're looking for an outcome; i.e., you want a dry crack free of significant dust and debris for best adhesion.

Thank you for your service. That is a good question, but we don't have the cost numbers on that project. Guessing...tens of thousands. And, of course, there is the prep work, the foundation keys, transportation, setting crew, and so on. There's a lot involved. But the advantages of precast sections like this in terms of quality control are a real leg up on traditional cast-in place.

@@DelawareT2Center Thanks for the nice complement, most appreciated. So you're best guess is that "one section" would be possibly $20k or $30k or ??? What would you recommend on how I could find out? Do you know who the manufacturer is? Any info would MOST helpful. Thanks! Mr Bowen Retired, Veteran

Looks like it was BEBO Arch Systems, who is associated with CONTECH Engineered Solutions. beboarch.com/bebo-arch-system

@@DelawareT2Center THAT IS SO SO SO FUNNY.... because "BEBO" was my nickname in high school because of the spelling of my name!!! ha! ha! THANKS of the info, most appreciated. Mr. B

Excellent question. My recollection is that there had been significant rainfall on the scarified material prior to placement of cement and homogenization. But they still would have come back after grading it to wet it again and then it would be necessary to wet daily for 4-7 days, depending upon the design. That's all a weasel's way of saying, oops, failed to get a shot at a water truck! See this project as well - th-cam.com/video/tHRE_LM904k/w-d-xo.html - there you see the water truck included.

It is a Mirafi MPV 500 polypropylene non-woven fabric.

Yes, it is support across a stream for an exit ramp from the roadway.

Yes. Unlike most other field testing methods, there is a fairly high bar to entry for this and not just because of money; there's regulatory issues, medical testing, security, etc. However, Troxler has now come out with a non-nuclear gauge and it will be interesting to see if testing agencies migrate, at least partially, to these over time. As expected, there remain some questions about accuracy under some conditions and I suspect that will improve over time. We'll see. Thanks for the input!

I don't recall for sure, but commonly these types of sections are connected with cables that provide post-tensioning. But there are a variety of connecting types, particularly when those structural concerns aren't the driver.

Agreed!

Glad it was helpful!

Thanks for viewing.

Glad you enjoyed it. We embedded engineering interns to the US 301 project and gathered some great educational video, which we enjoy sharing.

Rodolfo sets a good example for others.

It takes a whole team, right? Looked at your site, so you have the experience to know what you're looking at! Thanks for the comment.

@@DelawareT2Center hell yea man I love to see everyone do this type of work… stay safe always my brother!

We are not experts on the mix side. I would reach out to Slurry Pavers - www.slurrypavers.com/ - they're out of Richmond, VA and did the work here. You can also look at the resources at ISSA - www.slurry.org/ - a great industry association. Their Slurry Systems Workshop is in Las Vegas in January and that's a great opportunity to learn from peers across the industry.

All constructive dialogue is welcome; that's how we all learn. We don't do the work; that's Slurry Pavers out of Richmond, VA; we're observers and use these materials to educate local agency personnel about techniques and materials. You are correct that you can always improve in various ways and that's why it is helpful to look at operations and constructively critique. Thanks for the input!

Yes, for the right road at the right time, this can extend the life of the pavement and freshen up the look for some time.

Could be. RoadResource.org is a great resource for looking at pavement preservation techniques and there you will see anywhere from 3-5 years up to 7-10 years, depending upon the nature and condition of the existing bed; and of, course, the quality of the materials and craftsmanship putting down the chip seal. There is a lot of science in the materials and there is a good deal of art and experience in putting it down. We have some roads locally that, with a double shot of chip seal and then slurry seal (some would call this a Cape Seal), have lasted 20 years with little distress; admittedly, low volume, low speed roads. You are also correct on the expectations side. Chip seal will reflect the existing surface profile, so if the existing road has some challenges (not too many or perhaps you shouldn't be chip sealing), some wedge and leveling with asphalt ahead of it may be needed. But well applied chip seal should hold up to snow plows reasonably, particularly if mold board skids are used to keep the cutting edge slightly elevated. Thanks for the comment!

Did the same ahit to my street 20 years ago. Was so pissed.

Agreed. Best practice is to fully clean the crack. Spraying the weeds in advance can help the heat lance work even better, but there's not always the resources to do it. The better the crack is cleaned and dried, the better performance you can expect from the crack seal. But in practice, schedule, manpower, and the weather can complicate things and a good job of crack sealing is far better than letting those cracks erode your pavement.

I hope we have the translation correct. Seemed like you asked what was the goal or purpose. A good question. This road had become distressed beyond other pavement preservation methods (i.e., crack seal, microsurfacing) and had subsurface deficiencies. Simply milling and paving would have just put an expensive cover on a poor subbase. This techique re-homogenizes the existing asphalt and the drainage materials under it, mixes it with a small ration of cement and lots of water, creating a stronger foundation for a surface treatment. The result is a less expensive approach than removing all the material and replacing with virgin material. The road should be stable for many years to come and can be sustained with new surface treatment (probably chip seal followed by slurry seal) every 7-9 years. Merci pour la question.

you cannot b serious 🤣

We'll send them over! LOL

You are very kind. We may have a couple of longer format ones coming up; we'll see what the content provides. Some of our earlier ones were longer also - go back and have a look.

As motorists, cyclists, and pedestrians get accustomed to the facility, it does seem to be settling into a nice asset.

It certainly can be applied as a pavement preservation to asphalt in otherwise good condition (i.e., without advanced distresses). It does not provide additional structural strength; it seals out the surface to minimize water intrusion through minor cracks, stems the advance of oxidation and raveling, and can provide a little bit of skid resistance. More commonly (at least in our neck of the woods), it follows another treatment like chip seal. It is a low-cost treatment to extend the life of a pavement that has not deteriorated too far. Remember the central tenant of the pavement preservation toolbox - use the right technology for the right road at the right time. See also roadresource.org/.