We've got a road culvert replacement project coming up and i wanted to run this by you folks to make sure my logic doesn't have too many holes in it. Situation: Replace existing cmp pipe culverts on a two lane road with hdpe pipe culverts. We'll close the road down on a friday night to excavate and tear out old culverts. New culverts (3 barrels x60 lf -48" dia.) have to be in and road open by monday morning. My plan is to use a kobelco 160 or 200 size machine with42" bucket to do excavation work, walking it onto exist asphalt pavement via old tires to reduce wear marks. We'll need to excavate about a 30' x 30' section of pavement and dig down about 5' vertically to get to top of pipes. I intend to cycle one or two bobtail trucks for haul off, backing them up to the excavation and loading with the excavator. Each truck would have to cycle about 3 miles down the road to dump spoils. Shoring requirements are to be met via laid back slopes. We've got a few experienced operators on excavators, but i want to make sure that i'm not leaving anything out. Any thoughts on the amount of time it'll take me to hog out a +/- 30'x30' area, 5'-6' deep and load trucks? Assumption is that utilities are not an issue (heard that one before , haven't you!) Existing material is roadway fill-no hammer required to remove material from the roadway embankment
30'x30'x5' is only about 200 truck yards. It seems to me that you could haul it all out in half a day at the most. You should be able to dig out all of the excavation and pipe in one day. Three days should be pretty easy to accomplish if your materials are all on time.
Welcome to HEF crazycajun! :drinkup
Just prepare for the unknowns. Also have your ear plugs for the people complaining you have the road closed Why are they using such large diameter culvert pipes is there that much water moving through them ?
Hi Ford- existing crossing has 3 exist. 48" dia. cmp's. Constant creek flow so we'll try to divert/bypass water prior to tear out. Possibly sized for the lower frequency/high flow events.
don't wait for the trucks, don't let them dictate your pipe production rate. if you have to, pitch the dirt off to the side, load as you can with end loader. that way you get your pipe in when needed.
Good call. We've been looking at that Dayexco, and if the numbers work out geometrically, we're gonna try to get the downstream 20' or so x 3 barrels in prior to the shutdown, that way once we get cut to grade, all we need to do is stab into the new downstream barrels.....
I can see why they want 48" pipes :iagree You may want to have a trash pump on site to do pumping if the water starts flooding on you. You also may want some hay bails to set up a silt fence if this is a creek that may or may not have living creatures in it you want to keep the mud contained. As dayexco says you can bail the dirt up into a pile you may have to move it once bailing it with the machine.
Do you plan on using the existing culverts for the water diversion? Like having the water flow through one while you replace another and then have the water flow through the culvert you replaced and then replace the other two? How close are the culverts to each other?
Hi Red- good question on the water flow. My game plan right now is to go into the creek, say a week before tear out, and sandbag/plaster up the creek, leaving a diversion pipe flowing into one of the barrels of the cmp. Hopefully, this will help dry out the other two barrels somewhat. Plan is to replace two barrels and then divert the dammed water into one of the new barrels and rip out the last existing culvert. Good news is that the soil is fairly rocky below existing pipes' flowlines, so we will try to keep subgrade mushiness to a minimum....
We replace a lot of drainage pipe. I would dig a sump for a pump even if you divert the stream. I would stake straw bales down stream, out of the way. I wouldn't worry about letting the pipes dry out. Figure out the elevation that you need at each end just start digging. I always try to dig away from obstructions, poles, wires, banks. I agree don't wait on the trucks, keep digging just pile the dirt up along the road. If time gets short you can always work off the road on the up/down stream sides. Sometimes if time gets short we place the pipe that will be for the road, and then do the ends. Is the pipe getting head and end walls? The machine size sound goods, I use a G3WD Gradall or a 160 class machine. The buckets on are machine are small incomparison to yours.
Our rental pals have come through with a 210 kobelco for us with a 48" bucket for some serious dirt hog out (based on the dynamite rule-more is better, philosophy)! Hopefully we can forward some pics of us doing night work if it ever dries up down here.....thanks for all the handy advice
You'll be done with the excavation in a few hours, which is what you want. Watch out for backfill/compaction delays. Have two pumps on site incase one takes a crap on you. Eliminate single points of failure. pre-stage your dams for diversion into 2 of the pipes, build a sandbag wall on the one you aren't yet using and just open the wall, it's much faster usually. Dump dirt into a pile, load it after you've rebuilt the road. That machine will out-produce a truck even with very short truck cycles. Can you patch subgrade with cdf or concrete that is a quick setting DOT mix? (often ready for *traffic* ie at full design stregenth in 2 hours or less.)
Artherd- all good points. we're actually planning to do a very similar situation as to what you are suggesting. we'll dam up the stream ahead of any pipe/safety end treatment work, and plan to use 3-4" hdpe pipes for diversion of water. wall thickness is thin enough to allow us to shift the pipes back and forth between existing/new culverts. Pumps will be on stand by, but we want to try to keep pump maintenance/activity to a minimum. Heck, a couple hundred bucks we can build our dam and bypass piping. We'll be using DOT flex base for the full embankment (no nuclear densities will be taken) and then cement stabilized base for the top 10" with cold mix on it. We'll come back in a couple of weeks after initial consolidation and trim and put in hot mix. Should be a cool job if we can ever get in there. Closure postponed this weekend due to emminent rain. ARRGGGHH! Cost me almost 2K for message boards for advanced warning......
Grrr! That $2k recoupable as a change order under your municipal contract (weather sometimes isn't)? If you use CTS's "RapidSet" they make an in-house portland substitute that when we use it in their readi-mix, the entire result is hard and traffic ready in 1 hour. Could save you a day on that base (but the cost is more than double that of std portland! OUCH!) How are you doing your compaction? I'd use our wacker 82-sc trench roller over the whole area and work up in lifts. In competent grannular it's easy to hit 95% with relatively thick lifts. You could hot-mix it that weekend or worse case the next. Have you thought about offering your guys either daily or project based milestone bonouses? (ie, first day if we all get the ex out and hauled off, $50 beer money to all hands?) Good luck!
Hey Artherd- Sounds like we're on the same page. Yeah, i'm bummed about the mssg boards (subsidiary to traffic control monthly payment) but i'll take my lumps and be a good partner. Cool deal is, this Hancor pipe is somewhat new to DOT construction jobs here, so we'd really like to be a good contractor on this deal. pipe Backfill compaction: plate compactors, hand knifing under haunches zone 1' above pipe to final hot mix- we'll use a combination of wacker tandem smooth drum roller and our bomag trench roller, and then seal the edges with hand rammer. The big wacker is only about 5500 lb, so we can drop it into the excavation with the 210. We're gonna try to do something $$$ -wise for the guys for the long hours. We've got one 18 year old who doesn't think that he needs sleep and wants to play the whole weekend w/o sleep but we won't let that happen. Should be cool if we can keep the darn excavation semi-dry. We'll forward pics of the action.
Plates will work, assume you have a few heavy reversibles. I actually have a Multiquip 702 which is a *remote* reversible for 5'+ trenches, comes in real handy and in a pinch will pack cohesive soil too if it's moisture content is just right. It's 1500lb static weight, produces as much as 15klbs compactive effort. Reversibles are worth their weight in gold! I love the HDPE corguated pipe, easy to handle & cut, very strong & light. My customers love the fact it will never rust! Best! Ben.