cutting grade ready for emulsion.

[Scrub Puller]

Yair . . . Just curious (again). One of countries major contractors has been having repeated pavement failures with a realignment and resurfacing project going past our gate.

The crusty old Canadian dirt boss I started out with always banged into me that you could only cut down to grade . . . in otherwords you put the fill in high and hard and then cut off the top inch or so to end up at finish RL. Our finished sections would cut off shiny in the sun and were then broomed ready for bitumen.

These blokes here stuff around with the GPS working up to grade . . . sometimes running out a couple of inches of material. Even sitting watching in a line of traffic I can see the segregation as the gravel moves along the blade. They do a few passes with the roller and then broom it off and spray it and wonder why it fails.

It isn't very difficult but it seems the ability has been lost to put in a decent consolidated fill.

Any comments?

Cheers.

 

[TEC]

Well this just proves you should listen to Canadians and do exactly as they say.

Tom.

 

[stock]

What he was on about was what I refer to as over charging the fill then cut to level. This is how We used do it but the bean counters don't like double handling of dirt and want it finished to level. Putting fill in layers testing it every two layers for compaction and density.....................

 

[heosmitther]

Can someone please help me? Using a backhoe I have to dig a 50ft trench 4ft deep but the top 3 ft of the trench needs to slope at 1.5 to 1 ratio I understand the ratio that the trench must go out 1 1/2 feet for every 1 foot it drops for the top 3 ft what I don't understand is how am I supose to do this with a backhoe if its not obvious Im new to being a heavy equipment operator I have dug many flat botton trenches but never with sloping sides. Do I dig the 4ft down flat bottom then come up a foot and dig a 1 1/2 shelf into the side of the trench and repeat this until Im at ground level then knock the lips off with the bucket to acheive a slope? does the pivot point of my backhoe stay in the center the entire time or do move it side to side will I be able to make a 1.5 to 1 slope on a 4ft trench staying centered ? please if anyone can explain to me the procedure I need to use to dig this trench I would be forever grateful to them my very job depends on it. thank you

 

[Bluetop Man]

It isn't very difficult but it seems the ability has been lost to put in a decent consolidated fill.

Any comments?

Yes.

That's no sh*t.

The bean counters want to do what their notebook computers say. But the old Canuk was right. You fill, then cut to grade. Much faster. It's called efficiency. They don't teach that in college, but they do teach keyboarding, which automatically makes you a project manager at age 22.

Like a guy I worked for once said, "If you don't know, you just don't know."

 

[d4c24a]

Can someone please help me? Using a backhoe I have to dig a 50ft trench 4ft deep but the top 3 ft of the trench needs to slope at 1.5 to 1 ratio I understand the ratio that the trench must go out 1 1/2 feet for every 1 foot it drops for the top 3 ft what I don't understand is how am I supose to do this with a backhoe if its not obvious Im new to being a heavy equipment operator I have dug many flat botton trenches but never with sloping sides. Do I dig the 4ft down flat bottom then come up a foot and dig a 1 1/2 shelf into the side of the trench and repeat this until Im at ground level then knock the lips off with the bucket to acheive a slope? does the pivot point of my backhoe stay in the center the entire time or do move it side to side will I be able to make a 1.5 to 1 slope on a 4ft trench staying centered ? please if anyone can explain to me the procedure I need to use to dig this trench I would be forever grateful to them my very job depends on it. thank you

get yourself "V" bucket or a tiltrotator
http://www.youtube.com/watch?v=VwLMWtIhzg0&feature=related

 

[buckfever]

I don't have much experiance in road construction. When we do parking lots or put a pad in for a building we do it just like Scrub Puller said. Fill and pack past FG then cut to finish. Backdrag any small windrows or track marks and roll it smooth. Then hire a guard with a gun to shoot anyone that trys to drive on it after it rains.

 

[Scrub Puller]

Yair . . . heosmitther. You sound a bit desperate mate.

I'm no backhoe or excavator hand and thats a curly one you have. Depends a bit on access. Can you get to the sides and drag the batters up? how tidy does it have to be, is it rocky or nice clay, a lot of issues. . . I'm guesssing this is a safety issue.

In theory the top of that trench wil be nine feet plus the width of your bucket. If I was doing it without a "V" bucket or tilt-kit (and it had to be to some B/S Spec.) I would set up and bail and tidy the full excavation a foot deep as far as I could reach and then step in the foot and a half on both sides and do the same again till I got down to depth and tidy up the best I could.

It aint gonna be pretty. You are only talking fifty feet so if you aren't able to get side access to trim the batters a bit of hand work may be neccessary.

As I said, I'm no hoe hand and some of the other blokes may talk it to you different. I just replied because you clearly need a bit of help.

Best of luck and Cheers.

 

[Bluetop Man]

herosmither, it's done both ways, just depends on your personal preference, and that is determined by experience. Starting out, you should probably cut the ditch to full depth first a few feet, then pull the sides, and bring the drift along with you backing up. I put backing up in there because, yes, I have seen more than one new operator try to cut a ditch going forward. This only works with trackhoes for obvious reasons...best of luck.:drinkup

ps, OSHA rules govern ditching in the US. Every four feet down you must have a bench. After one outfit I worked for had a guy die in a cave-in, they went to a bench every three feet. Lots quicker to get out of the hole. Check the OSHA website for particulars.