Any Excavation Professionals Feel Like Giving Advice?

[herefromthere]

When they cut my timber,,
the loggers built a road, 1/8 mile long.
They stripped the topsoil, and left a SLIGHT side to side grade.
Next the soil was covered with railroad ballast.
Then, after running in the RR ballast with a D6 CAT, the road was top-dressed with 57's

The ran 160 loaded 18-wheelers over the road during the wettest spring we have seen in over 40 years.
The trucks all had overload permits, they were not allowed on the interstate due to excess weight,
so, they must have been significantly over 80,000 pounds.
The road is still perfect, 7 years later.

There's a lot to be said for RR ballast. (That's 3/4" and 2-1/2" screen, crushed in my area.) I put it over less than optimal base in two locations, and it worked even better than I thought it would. I always remove as much topsoil as possible first.

In another spot, I used it to build up an area before putting 1-1/4 minus surfacing over it for a steep hill on my driveway. It packed and keyed really firmly over a pretty short timeframe without using compaction equipment. The delivery dump trucks compacted previous layers, then my tractor did more when grading. Finally, I just drove my car and truck on it to finish it off.

At a nearby logging operation, they put a thin layer of RR ballast over some really old pit run base that they barely scraped some of the organic stuff off the top, and it held up to log trucks and equipment in the PNW wet season.

For the OP, the 2nd contractor sounds like they have the best plan/materials.

*Edit: Agree with the geo-textile proposed by the 2nd contractor, but I feel like I'd want larger material for the base. As a NON-professional, I'm only going by internet edumuhcation, but it's what worked in practice for me as well.

 

[Elroy1986]

I meant to specify a product I plan on using. Truegrid
Not cheap but there are other manufacturers. But the specs on truegrid are impressive. You can drive heavy equipment on it before it’s filled with material. You can grow grass as well. 1.8” thick. It can handle 250,000+ lb vehicles with 1M psf compression strength. They have their own design specs. 2” to 8” base, depending on application. But definitely use the woven geotextile. It’s stronger than the non-woven, which is used for French drains. I’m not advertising I’m just impressed most by this product. Your dollar.

 

[edgarrian]

I find it shocking that the third guy said he would not strip the top dirt. that to me is crazy. I assume you made ur deciosn since there are so many responses

 

[aircommuter]

One thing for sure if you wanted professional contractors you came to the wrong place.
Stripping is a must, leveling is a no. Why would you want water to sit there? Even garage concrete slabs are required to have slope these days. I can help with the sub soil once I know what is down there. Even a couple hand auger holes would help. Test first then design.

 

[GrumpyL5030]

I am in the process of talking to a few local excavation companies in regards to a project. It's a simple project (they all have said this), but each has their own method of completing the project. I've been wanting to get this project done for a while now, and life keeps on getting in the way so I will be hiring this one out to a professional.

The project is a 30' x 30' gravel parking pad. The area where it will be installed is currently grass and soil. The area slopes approximately 1.5' right to left over the 30' area and 1' front to back over the 30' area.

My question is: is there truly a "right" way to do this?

One guy said he would strip the soil down to clay, use #1 and #2 limestone as a base, then top dress with #57 limestone

One guy said he would strip the soil down to clay, use geo-textile fabric, use #1 and #2 as a base, then top dress with #57

One guy said he would NOT strip any soil, use asphalt chunks and grindings as a base, the top dress with #57 lime stone

They all claim that their way is the "best" way.

So, I am seeking an outsider's opinion which method seems the most logical to go about this project.

Thanks

Use the second guy. Textile fabric will keep the mud and loose soil from coming up into your limestone while letting water drain down through it. Road grindings aren't a good base for anything unless they're ground down to very fine like you could use to pave with. The stuff I got from the county where I live is a mix of "fines", 1" and 4" - 6" chunks of pavement, making it all unstable. Get unwashed limestone with all the stonedust in it. It locks up almost as hard as pavement. Good luck!

 

[MGP4506]

I’m not trying to highjack the OP’s topic, but this relates with regards to site prep.
How would this work if your site does have underground springs? You obviously can’t dig out the topsoil without having the holes fill in with water and you’re not going to dig down to anything except clay and more water. Would you have to use a different method?

If there are underground springs you have to add drainage. Water is your enemy when doing something like this.

 

[olenjohn]

I am in the process of talking to a few local excavation companies in regards to a project. It's a simple project (they all have said this), but each has their own method of completing the project. I've been wanting to get this project done for a while now, and life keeps on getting in the way so I will be hiring this one out to a professional.

The project is a 30' x 30' gravel parking pad. The area where it will be installed is currently grass and soil. The area slopes approximately 1.5' right to left over the 30' area and 1' front to back over the 30' area.

My question is: is there truly a "right" way to do this?

One guy said he would strip the soil down to clay, use #1 and #2 limestone as a base, then top dress with #57 limestone

One guy said he would strip the soil down to clay, use geo-textile fabric, use #1 and #2 as a base, then top dress with #57

One guy said he would NOT strip any soil, use asphalt chunks and grindings as a base, the top dress with #57 lime stone

They all claim that their way is the "best" way.

So, I am seeking an outsider's opinion which method seems the most logical to go about this project.

Thanks

None of the above. You didn’t say what soil type is there now or what you’re parking on it. I will figure cars, pickups, trailers etc. with clay subgrade. I have built roadways and lots for over 30 years all over the country. For a simple parking pad - strip the sod and topsoil. Place a 4” drain pipe out the side of the stripped area so any water in the coarse stone base can drain out. Bring the site up to 4” / 5” below finished grade with coarse crushed stone about 1” / 3” size. Can be limestone, crush rock, crush concrete - whatever is most cost effective in your area. You could also bring the area up to fairly level keeping it about a foot below finished grade with clay but make sure it is compacted very well. If using the clay, a sheep’s foot roller works best for compacting. Cost of the clay may not be efficient money wise. Just depends upon local conditions. Put down 8” thickness of the course stone. Top dress this with smaller crushed stone. Strange as it is, depending on local quarry, they may number it differently. #57 is generally is 1/2” to 1” size - no fines. Do NOT top the 4”/5” with that. It will NOT compact tightly. It needs fine material to fill the voids between every stone. #21 is generally about the same size stone but also have fine particles and will compact hard like concrete. This can be gotten in crushed gravel / stone or limestone. Be sure the pad slopes to drain. Since it already side slopes let it drain the same way - left to right and fairly level front to back. About 3” slope should be enough. The geogrid / fabric is a waste of money for this. Water the top stone as it’s placed and compact it. Some quarries will actually wet the limestone before trucking it. “Pugged” is what they called it. Dress up the perimeter beyond the pad with the material stripped at the start. I have a 500 foot driveway done with the #21 limestone 5” thick. Have ran redimix and loaded dump trucks on it. It may need to be top dressed after a year but simply hand spread new material in any low spots you missed. They will show after a hard rain. Top may be a bit soft in the spring when the ground thaws but will tighten up a soon as the freeze leaves.

 

[charlessenf]

The project is a 30' x 30' gravel parking pad. The area where it will be installed is currently grass and soil. The area slopes approximately 1.5' right to left over the 30' area and 1' front to back over the 30' area.

So, I am seeking an outsider's opinion which method seems the most logical to go about this project.

When I contracted my rear driveway, I first called the state DOT to ask for specs on building roads in my state. Believe it or not, there are 'standards.'

Several of the local boys bidding offered ideas and even argued with key aspects of "my" plan. Needless to say, I prevailed and the read drive's been working out just fine for teh past - has it been - five years or more.

You can look at GeoFabric sites online to get an idea of what the MFGs say it is designed for - they know what they can sell to professional (educated) engineers and designers, etc.

Frankly a 20:1 pitch don't seem to warrant textiles! But I don't know for a fact. When I wanted to replace a retaining wall that had been constructed when the house was built (sixty years ago?) out of stucco over 8x8x16 Concrete block, the guys I spoke to wanted all manner of modern accoutrements added to the work plan (and my costs).

But if it worked all this time without that stuff . . . why do I need it now?

 

[Gord Baker]

There are many ways to do things. Geo Cloth allows moisture to pass through it, but not organics. Dig down the High end/side to match the low point elevation.
You can put some interlocking wall blocks at that corner. Follow local best practices for build up and then asphalt or 3/4 Crusher run. 3/4 down to fines for top layer.
Measure out 30 x 30'. Not very big. 3 cars?

 

[paulsharvey]

I will throw this out; in general, avoid Northern contractors down for the winter. Mostly con-men, and over priced, under deliver, and sell people on some odd notions; that may be appropriate where they come from, but they don't know local soils.