Hello all,
I purchased an excavator a couple of years ago to help develop a piece of land in CT, and taught myself how to run it (sometimes the hard way). I have become proficient at digging stumps, burying rocks, trenching for utilities, septic system installation, road building, etc. However, I’ve never excavated a basement.
What I’ve learned to date is that the last 100′ of trench I dug, was done alot cleaner and smarter than the first 100′.
So, I’d like to get some tips on how to manage digging the basement.
Things like:
1. How to locate and manage spoil piles
2. How to actually dig the hole. I know about stripping topsoil, but what are the logistics for the rest (side to side? in strips? in layers?)
3. Recommendations for a decent rotating laser level that doesn’t cost a fortune (I won’t be using it for much else)
4. How much access around the hole needs to be preserved for concrete trucks
5. What I can do to avoid throwing spoil twice
6. Advice on backfilling (I assume the first floor deck needs to installed prior to backfilling)
7. Anything else that may be helpful
The machine is a CAT 315 LC. The footprint is basically a 40′ x 50′ rectangle with easy, open access on 3 of 4 sides (garage exists on one side about 12′ away). The soil in the footprint has not been disturbed, and will hold a vertical cut easily. I don’t expect any issues with water table. I do expect to encounter very hard glacial till at a depth of 6′ to 7′, which is difficult, but not impossible, to excavate.
Thanks in advance for any help.
–Brantley
“If its not hard, why do it?”
Replies
Excavating
At 10 feet deep that's about 740CY of material, plus expect some expansion (swelling, 10-15+% depending on soil)
Locate as much as possible into it's final location, if some going offsite, then right into truck and away it goes.
Sounds like you know that there will be different types of layers of material, there my be some advantage to keeping seperate, especially if you have a good backfill (low expansion, well drained) vs a poor backfill type (expansive, poorly drained), etc.
I'd probably ramp in/out at one location for access, for tamper / roller if required to tighten up the grade, but that could be lowered in and out with the excavator you got. It's nice to have access for forms, etc. Personnal preference here.
I like to keep the concrete trucks "well away" from vertical unshored excavated holes, sounds like you got good access too, but I like the overhead pumper truck with pinpoint placement. Saves on everyone back, and there is less waste, etc. You can keep the trucks well back.
Regarding "avoid throwing spoil twice", Good Planning, Period.
You got your drainage well handled hopefully.
The 315 is nice. you can dig it just about any way you want. But not if full depth trenches lenght wise obviously, you would need to work your way sideways.
Sound like a great job, good luck.
Basement excavation
Thanks for the feedback.
One more question. Since you attached a photo of a CAT 315, I assume you own one or are familiar with one. Does this machine have the ability to reach to the center of the excavation (39' x 50' x 8' deep) from the perimeter of the hole? Assume a 3' over dig all around for form access. I'm just concerned about working my way out of reach, and not being able to fine tune the final grade.
Reach Capacity
Reach / Range Dimensions are dependent on 1). stick lenght and 2). Foreboom pin hole location.
I can't answer your question. If I had to guess, NO. w/ 98.7% probability or higher.
If you had a 320 L Long Reach, good to go at 51+ feet reach (from King Pin) at groung ground level.
But your talking 39/2 + 3 = call it 8 feet deep at 23 feet from front of tracks located right at edge of excavation.
Download a Caterillar Performance Handbook at:
http://www.pdfqueen.com/pdf/fr/free-caterpillar-performance-handbook/
Or, contact your local Cat dealer and see what they say.
Please recall, my personal preference is a small "ramp in" at one location. Not that tough to back fill.....
Good luck.
Basement excavation
I'll take your advice on the ramp. That will allow me to fine tune grade if my concrete guy needs it, and will allow easier personnel access in and out of the hole.
Thanks.
I have a Robilaser - it's not too bad -
http://www.amazon.com/C-R-LAURENCE-R0B01-Self-Leveling-Rotating/dp/B001Q5GRVY/ref=sr_1_1?ie=UTF8&s=hi&qid=1271729860&sr=8-1-spell
I bought mine 'reconditioned' for $200.
I did something similar ... fresh out of college and built a house w/ full basement. We rented a backhoe and went after it. I'd generally not do it in layers, you may end up w/ access problems and I don't see an advantage. It was interesting to practice getting a level scoop ... I learned to pull both nobs at the same time and it would pull the bucket at a level cut. You can be pretty darn accurate doing this. Easy to practice on the shallow cuts until you get used to how the machine can help you.
I'd do it in side to side approach. Once you get to say 6" of depth move back and then start again. You can do clean up grading after you've come back at least a row.
I'm guessing you'll only have like 3 rows. Keep your machine away from the edge. You'll have fun! Just like Tonka trucks.
I'm not the expert ... just my limited experience and teaching myself. As you can see others have words of wisdom for you.
Sounds like you have a level head, so trust the intuition and go for it!
I'd rent a level ... you should only be a day doing this. I did a complex footprint in a day in winter weather. We made the mistake of piling the stuff next to the hole ... so backfilling became awkward as we used a bobcat ... had no idea what we were doing ... but we did it w/out much event ... OK I rolled the bobcat, but that really wasn't a big deal either!!