Are there any road builders out there.

We are putting a driveway/road in, 200m long (will make a good drag strip) we have had 2 quotes about the same price. both guys reckon there's is the best solution.

1st guy 150mm roadbase 25mm ashpalt covering

2nd guy 150mm large roadbase, 100mm stabilised roadbase 10mm first bitumen seal coat, 7mm second seal coat

Anyone have any idea which would be the better option? (the second fellow lives next door to rod penrose)

It is going to depend on the soil type we are talking and what sort of flow rate moves through it .

I am going to guess that you don't mean 150mm roadbase as in 150mm dia agriate. Do you mean 150mm deep before or after compaction ?

Also what are they planning on doing, building up or cutting down ?

What basecourse are they planning on useing and what level of compaction ?

What sort of load are you going to put on it and what temp are we using for design max ?

As a general rule ashpalt sucks for anything near shed or trees, grass will also grow through it if not done correctly. The better the subbase the thinner the wearing course can afford to be. There are many different mixes of ashpalt on the market and you really need to compare apples to apples and oranges to oranges.

I would love to give you more details but I can't really comment on a design when I am not sure on the specs or environmental variables. You may wish to check with your council and see wht sort of sub course they are using.

Are we talking hot mix emulsion ? Are the compacting after laying are they spray sealing it or dry laying it ????????

ie do i know anything? well not really.

Out of 6 guys we received 1 written quote and 1 verbal quote and 4 no shows.

The soil on the block is a silty clay, flat and we will need to drive trucks down the driveway to build a house and get some fill in.

The first guy is cutting in (not sure about the second), 150mm compacted roadbase + 25mm asphalt. As teh quote was verbal and we are still waiting for his written one not sure of specs.

The written quote was the 2nd guy and it is as follows
1. prepare site supply and lay subgrade to a compacted thickness of 150mm
2. Supply and lay cement treated roadbase to a compacted thickness of 100mm
3. Apply emulsion 10mm stone and compact
4. apply 2nd coat of emulsion + 7mm stone compact.
He was 2000 cheaper than guy 1, but verbally quoted $4000 extra for asphalt bringing his price to $2000 higher.

Should we have had this designed by an engineer first? The first fellow is a civil engineer, design/construct contractor.

From my (10 years old) previous experience, 150mm+10mm will not do if you will have loaded trucks on it. When I designed and built access roads for loaded trucks, we used 150mm cement stabilsed base.
Raf

From my (10 years old) previous experience, 150mm+25mm will not do if you will have loaded trucks on it. When I designed and built access roads for loaded trucks, we used 150mm cement stabilsed base+50mm asphalt
Raf

[Edited on 20-7-2003 by karmannghia60]

First up the strength of the road is given by the compaction and nature of sub base. The wearing course is there to protect the sub base. Now we are builing a DRIVE WAY not a ROAD so traffic is not a real concern. The trucks that you will have driving on it for your house will be say under 20 Tonne ( 8T Truck with Load plus heaps of fudge ).

You are unlucky at this exact moment because I am running a vertical construction site and all my horizontal works texts are sitting on my desk back in Brissy. Off the top of my head working on teh variables I have I would go with teh 2nd guy.

Ask what he is compacting with.

You do not need an engineer, if in doubt goto the library and get yourself a road building book. You will find a construction table which tells you sub base type and thicknesses . It will talk about CBR which is Callifornia Bearing Ratio, work of the average it offers in the Brisbane area.

A 150mm roadbase should be fine, a 17mm wearing course should also be fine. I am guessing it is hotmix.

I will talk to some of my road builing engineer mates and get you more specific info if you want. I would need more info though.

Sounds like the 2nd guy is the way to go, cheaper and builds a 250mm total compacted base.

the only questions that remain are:
1. Should we spend an extra $4000 to get 25mm asphalt instead of a 17mm total spray seal.
2. Which would be the best to use as a drag strip (neighbour put in a dirty letter to council to try and stop the works)

3. is a vertical construction site an underground mine?

Cheers
Kurt

25mm ash will be a better drag strip and is is more elastic than the spray fill with ag. I would not say it is worth an extra $4000 though.

Once you have a sub course down properly you can always get a secondary seal coat added years later with no hassle at all. This will keep it looking good and functioning well.

What council are you dealing with ?

Just make sure you never spill anything fuel oil related on either on them or they turn to POOOOOOO.

Cheers,

Oh yeah, vertical is above ground. I am working on a steel portal frame 2 story 40m x 60 m office block in Tonga. If the rain ever pisses off the boyz will get the condeck down and we can pump the suspended slab.

Brisbane City Council