steel plate thickness query (amongst others!)

[JimK]

Next spring I'm going to have to revisit the access track/bridleway which is deteriorating again despite regular topping up with MOT.

So thinking of casting in situ two 18 inch wide concrete "tank tracks" for 150m!

Challenges will include:

1 keeping costs down.. mixing own concrete, doing a "section" at a time.... or sod it and try and do 4m3 runs at once with small ready mix trucks?

2 Keeping access open (incl vehicles) during concrete cure stages:- Road forms or equivalent pegged for sides and a (possibly bolted down) steel plate top for wheeled traffic whilst initial curing takes place

- how thick a plate? thinner is cheaper and easier, but at what thinness will it bend/buckle and backfire??

3 Shaping the concrete to avoid sharp corner edges (horses etc) - perhaps some sort of curved top (in section) road forms, or similar or fabricate something to do the job... or will I be able to simply knock the sharp edges off with a big hammer after a few days curing when "mould" removed?

4 Do i need reinforcement? plan on 4inch average concrete depth for cars, tranny vans, small oil tankers.

5 Any way I could easily replicate (or just give a passing impression of) stone flags as I cast it? (other parts of the track have these still in situ - it would be "nice" to give a nod to the vernacular..)

what does the group think? do-able? what've I forgotten/underestimated/ failed to appreciate etc--- you get the picture - Help!!

Cheers JimK

[JimK]

On Dec 12, 4:20 pm, JimK realised the subject was naff so changed it

[Phil L]

How wide is the overall path? - could you not do one full length track, rope it off and allow drivers to use the other part of the path, then do the other one a week later when the first has cured?

Steel plate will have to be at least 8mm, and thats gonna be expensive

[cynic]

As a rider, I'm delighted that you are not proposing to make the whole width of bridleway into a solid concrete road. Horse traffic is best provided for by a firm but yielding surface. Concrete or tarmac do not make for compatibility with hooves.

[Phil L]

trying to mix 15m3 of concrete manually is a thankless task, readymixed is the way to go, but this is likely to cost you over a grand

you can run a spade along the sharp edge and round it off a bit.

4 inch will probably be ok, but I'd get some thin steel reinforcing in it, just to give you a few extra years

you can run a jointer across it before it finishes curing, to give it some 'joints', but trying to mould any kind of pattern onto the face would be time consuming and probably a waste of time as I wouldn't expect it to last very long.

[JimK]

mmm I shall have to point out to those equine riding whingers the favour I am doing them!

The project should hopefully curtail the "free for all gallop" that seems to be a regular abuse by some riiders judging by the hoof marks/ divots......

JimK

[JimK]

not wide enough afraid.

how much is expensive?

I'm imagining 18" wide X "liftable lengths" - load 500kgs say (2t /4 wheels) spread over contact patch of average car tyre (4"x2"?) ... a few vehicle movements a day....it will have curing concrete right under it too.....

Cheers JimK

[JimK]

extra rad thought - timber top? ply? how thick rqd?

cheers JimK

[Tim W]

JimK wibbled on Saturday 12 December 2009 19:13

Is it not wide enough to set one track at a time, allowing vehicles to drive straddling it, then the other track with the vehicles straddling that one?

Or is this road just a vehicle width?

Off the wall idea:

Could you work with a "precast" approach? Cast the tracks in the centre of the road, including reinforcing mesh, then slide them across by the 2-3' required to have them in the correct place? That will limit you to perhaps

2-3m cast lengths.

Assuming you were planning on having a digger handy for trenching with the direct pour approach, the digger might be able to drag and drop them into the trenches that you cut at the end. Disadvantage: you need to either cast flat and trench flat so the strips bed well enough, or line the trench with some sand and be fairly confident of bedding them. 2nd disadvantage - lots of joints.

Dunno - maybe there are improvements to that silly suggestion that might lead to something that would work?

[JimK]

yup single track - just!

mmm I'd not thought of exactly that approach (i.e. using centre) but was hoping to avoid digger expenses altogether plus problem of what to with (almost) perfectly good MOT etc that will be generated - it;s a perfect sub base for concrete after all !! also casting in situ will (i hope) ensure "perfect" contact with the minor undulations of the current surface thus minimising early cracking/failure etc?

er not sure... I was kind of expecting them to be needed re expansion?

- and they would be there anyway if I proceed with my rough plan A of little and often....

cheers JimK

[NT]

Anyone know if this is workable?

Is there any possibility of repairing the MOT1 where needed, rolling or whacking it, then pouring a binder on/in? Such as cement slurry or tar. Then adding a tar topcoat to stop rain saturating and freezing.

There's then need to close off road access for curing. Also no need to but the sand or stone parts of the concrete. A 3rd is far less and easier mixing.

NT

[Tim W]

NT wibbled on Saturday 12 December 2009 22:22

Now that you mention it, perhaps spraying with tar would be an option. As long as there is a clean (ie un muddy) top layer, then it will tend to create a weak tarmac (weak because it won't get fully between the rocks, but it out to generally bind them).

However, if the OP can't keep MOT down, I'm assuming that the underying ground is very unstable?

[js.b1]

Plastic mesh with grass? Basically something to bind the MOT together, paying for concrete is a lot of effort, money & future expensive repairs (just pushes the repairs further apart).

[Tim W]

JimK wibbled on Saturday 12 December 2009 20:06

It's unlikely to fail if you drop a bit of bar in it as you go (I thought about mesh, but a couple of lenghts of light rebar would probably be good enough). But of course, it's all more complications.

Anyway, if you don't want a digger, then it will be painful sliding what are basically large cast beams around.

True

So in all, you are planning on pouring concrete on top rather than flush with the existing roadway? That makes a difference...

Just to clarify - how long could you hold off vehicle traffic after each pour? How long could you avoid anything larger than a car? You might get away with a car on top relatively quickly. 10 tons of fuel oil laden tanker would be different though.

[dennis]

Are you sure the problem isn't a lack of compaction on the MOT? Have you run a road roller over it?

[NT]

I suppose really the only permanent solution is to dig the road up and lay enough depth of hardcore and MOT1, roller it, then add tarmac. Anything less will break up sooner or later. Its a life versus budget call. Concrete roads do last decades, but there's no chance of vehicles passing for days.

NT

[Tim Lamb]

In message , "dennis@home" writes

Groundwork Trust laid a crushed concrete topping on our by-way 3 years ago. I have watched the appearance of *holes* since then. The lack of a significant fall and proper drainage led to initial puddling and then hole creation.

Fingers have been pointed at heavy farm vehicles but these rarely move at more than 6-8mph and have cleated tyres which tend not to flush water out of puddles. I believe the cause is car traffic probably travelling at less than 20mph. Any water standing on the surface is flushed away together with any grit or fines. These form *walls* around depressions. Slight surface depressions collect more water and accelerate the process. Eventually the hole reaches 2" depth with another 1/2" wall and close to traffic calming bump height!

At a rough estimate there are about 20 vehicle movements per day: 10 in and 10 out. Mainly intellectually challenged folk who ignore the *no through road* sign in obedience to their navigator instructions.

Jim has not explained the legal status of the route but it is clearly very narrow and also used by horse riders. If this is a bridleway with vehicle access rights he should expect strong resistance to any interference with the surface unless agreed with the local Highways officer. I think concrete *rails* 4" above the main surface would be considered dangerous to other users. I know he is trying to do this at minimal cost but think the concrete should be in shallow trenches with the surplus MOT used to fill the middle.

A much cheaper alternative would be to level off the holes with a coarser material than MOT as soon as they appear.

regards

[JimK]

exactly correct! we have bad/no drainage problems outside of my control (different owners either side)

nearly - correctly it is my road upon which there are rights for the rest of the world to ride horses, walk and cycle It's primary purpose is access for me to my property not for anything else - that's secondary...like other highways...

hence my plan to round the edges of the concrete (see OP) how else will it be dangerous? the middle will eventually start to fill up with horse s*1t/grass anyway?

fill the middle ? if concrete is trenched - what middle?

what sort of material do you have in mind?

cheers JimK

[JimK]

you seen how much they want for it?!?!

sounds OK to me :>))

JimK

[JimK]

Yup that is my plan A (sorry if not clear in OP)

overnight probly

months

mmm how quicks relatively quickly!?

cheers JimK