Byway - Dtp 1 sub-base and road planings cap

[PHILLIPBL]

I need to "refurbish" a 500m stretch of byway, to be suitable for bridleway and light traffic (to service a few houses, including mine). The byway looks like it is flint with clay binding the flints together and has been there for at least 150 years. The byway now has a lot of potholes which fill with rain. I tried compacted road planings, but they were simply pushed out of the pot holes by car wheels. I am now considering filling in the potholes with DTp 1 crushed concrete (compacted) and caping with compacted road planings. Would this work?

Should I fill in the pot holes and add a further 100mm of DTp 1 (compact) and then add a layer of road planings and compact those too? 100mm DTp over 500m at 3m width works out at 300 tonnes! Is it worth it?

Is it worth lining the potholes with TDP115 geofabric? Will it stop the fines merging/washing away?

Look forward to receiving some advice!

[Dave_L]

Whatever you do, it's going to be expensive.

Spreading 300t of stone - how do you envisage doing that efficiently and accurately?

It's a paving machine job, not all operators will run stone through their machines.......big machine = big money I'm afraid.

Who is going to be liable for the repair/resurfacing costs?

The flint stone surface you have - how 'level' is it, apart from the potholes?

[PHILLIPBL]

Many thnaks for your reply.

I was planning on having 20 tonnes delivered every few hours using a dumper to do the carting and the dozer of a 3 tonne Kubota to do the levelling and then using a vibrating roller to do the compacting. We want to keep the width to a single lane 3m width. We do not want to go to the expense of edging if we can help it.

The flint is reasonably level and as hard a nails, apart from the pot holes. A little of the sides has broken away in only a couple of spots and there is a small amount of rutting. A few of the pot holes are 2m wide and a foot deep ?

The idea of the compacted road planings is because the council have offered as many loads of road planings as we need (it is a public bridleway, but a private road, so the council have some obligation to help). Future maintanence will be up to the residents, as the council will do the bear minimum, i.e. to keep it good enough for horses (without carts).

Can I get away without using specialist big machines?

[Dave_L]

Potholes 2m wide and a foot deep?? :rock:

[matt h]

they're the equivalent of inverse speed ramps!

[PHILLIPBL]

You are not wrong; once the avenue is sorted, we were thinking we may have to put road humps in to slow the traffic down again!

Looks like I need some large stuff to put in the bottom of the holes. What's should I order up - 20 tonnes of ??? Will the big aggregate suppliers offer this?

Is compacted road planings sufficient to protect the DTp 1 sub-base from being washed away?

[Dave_L]

This is a similar job that we are currently doing, although the deviations in the existing surface aren't as great as yours.

Entire track stoned up with scalpings (194t) and compacted with large vibrating drum roller. Has gone down very hard and gives a good base for the tarmac layers to sit on.

Tommorrows job is the tarmac layers (basecourse and surface courses, 250t combined)

Existing surface beforehand.......not that easy to tell really.





Track, stoned up ready for tar


Where it all happens!

[PHILLIPBL]

Many thanks. Looks very similar! We tried a small stretch using road planings vibrated in with a roller. Where the track was level, the road planings have formed a good wearing surface, but where there were potholes, the road planings were simply squash out over a period of about six weeks. This is way I am thinking about simply filling the holes with a good sub-base and compacting well and then covering with planings.

The plannings will then form a wearing coarse and a nice cap to prevent the sub-base from being washed out by rain - or at lest that's what I am hoping. How long do recon this will last? Will we improve longevity by adding a further four inches of sub-base (300 tonnes!)?

[Tony McC]

The plannings will then form a wearing coarse and a nice cap to prevent the sub-base from being washed out by rain everywhere

??? In your dreams they might, but in the real world, they'll scatter everywhere and you'll be back to potholes in a matter of weeks.

If you topped-off the planing with a surface course, they might just do the trick, but as a running surface, they are fit only for farm tracks used by 4x4s and David Browns.

[Dave_L]

All complete.....

Laying 75mm 20mm basecourse.....note the camber set into the bed of the machine?



and the best bit of the job.......pulling away from the finished surface! Topped off with 10mm sma surface course.



Crap photos I know, I must remember to take a proper camera with me at times!