The Brew Cabin

I'm working on a 1200 sq ft driveway project with 4" x 8" x 2 3/8" pavers over 3/8 chip limestone base (CA-16) and sand. I rented a compactor today to compact the first 3-4" of base material that I have down and I'm wondering how you know you have compacted the material enough? The rock doesn't shift when I walk on it, but after about 6 passes on the material I still have some spots that if I run the 8" x 8" hand tamper on the rock seems to shift more. I'm a bit confused and looking for some guidance to know when enough is enough. Thanks.

As I am not familar with the 3/8" chip (CA-16). Is that a stone base that is a graded aggregate going from fines to the 3/8"? What I refer to as CR6?

Just wondering because if it is "just" a 3/8" chip with out fines it would not compact to a tight surface and explain why there is stone shift even after 6 passes with your compactor. Probably obvious to others what the (CA-16) is. Anyone? Before I can answer what else may be a issue.

LM

Walking on the base, and stomping on it with your feet is a poor test of proper compaction.

Your base may too wet. Grab a handful in a ball, and if it holds its shape it may be too wet. If a base is too wet, it will act like a slurry, and not compact well.

On the other side of the coin, if it's too dry, and has too many larger particles, the base not "lubricate" properly, and not compact properly.

In the States, if you don't have the time and resources to get a Nuclear Density Gage (and for a 1200 sf driveway, why the heck would you?) an easy test is to try and drive a 10" spike into the base with a 28oz hammer. if it goes in, then you need to re-compact. . . . I'm not sure about those numbers, but you get the idea!

IIRC, you should have to get a 36oz mallet to drive the spike in to pass.

Inches? Ounces? Square feet? What century is this? ;)

Quote: from TonyMcC on 12:08 pm on Aug. 10, 2004
Inches? Ounces? Square feet? What century is this? ;)

HA! You can tell I live in one of only two countries in the world not to covert to metrics! :)

Since my 3/8" chip doesn't have many fines could I correct the problem by adding a little bit of sand at a time and compacting it into the chip? The location that I have this 3/8" chip as my base material is on the walkway from my driveway to my front door. The driveway itself is a year old packed gravel that looks almost completely like dust. If I don't get the rock base material compacted really tight together am I looking at the possibility of the pavers wanting to shift over time?

Hmnn,
I have never tried adding sand/fines to a existing stone chip mix. So I am not really qualified to answer the question. Any one else have any experience with this?
LM