or they also call it cast-in-place. its a cheap storm drain pipe thats cast in the ditch via a "boat" . its kinda a pain in the ass to dig cause the grade is very critical. they like it within a half a tenth. ive seen some guys get it within a hundreth..i'm not one of those
First of all, give us some background on the project. Second, we need some pictures of that machine in operation. I have never heard of cast-in-place RCP.
they are going to pour tomorrow..i'll take some then..its not rcp..there is no wire in it
Thats wild, never seen anything like that on the east coast.
I'll buy you lunch if you can get it within a hundreth with a PC600. That's a big machine to do fine grading! and that bucket?? never seen any like that before. Nice work!
you're like mad max with all those crazy buckets
i'll second that. thats a wild bucket:drinkup
nice job keep the pic coming have never seen that being done find it very interesting
How much of the time do you have the target on the bucket like that?Do you just attach it when you need to check your grade or can you dig with it on there without damage to it? I cannot imagine how that cast in place pipe can be very durable but it is a new concept to me and I don't have any history to draw upon.Ron G
i was curious about the process so did a bit of digging. cipcp has been in use since 1922. it is supposedly about 30% cheaper than pre-cast, it appears more labour intensive to install if what i read is correct. tolerances of the u shaped trench have to be quite accurate to avoid either cost blowouts in excess material required or boat jamming due to a tight trench. seems that unless you are very experienced at this you wont get a look in as a contractor. i get the sense that the boats tend to be proprietary stuff made perhpas by/for the contractor, there doesn't seem to be any company flogging them on the net. interesting. seems fairly commercially risky tho.
its durable enough alright ron. plenty of tech data on cipcp on the net. the bucket is (so i understand) slipped on for forming the final trench, the thing needs to be sharp and each bucket is sized to a particular pipe size. if the material where the pipe is to be laid is suspect they excavate, part fill and compact then re-excavate with the u bucket (which seems to be laser guided.)
ok guys..they poured today..you are right about having to dig close grade..i can get it within 1/2 tenth..ive seen guys get it closer, but then again thats all they do..i usually dig this stuff once every 2 years. i have dug from 30" to 84" sized pipe. the laser clamps down on a pole we weld to the bucket. in actuality it should be on a bracket that sits out a little right over the teeth for the truest grade. but my company isnt that much of a perfectionist. there are a few companys here in the valley and thats all they do..there is a pic of some pipe that was poured last year by one of those companys that we had to take out for realingment..there work is awesome. we rent the boats and forms and buckets from a local company. it is true its a little more labor intensive,especially when the guys have to crawl inside the pipe to knock and turn the forms..i guess it can get to 130 degrees in there, but the cost savings is really something. ive been told that if you have 1000 feet of 60" to do at a cut of 9 ft, its cheaper to dig,pour and backfill then to just pay the trucking on the pipe, figuring a 50 mile one way trip..thats not accounting for the cost of the pipe, just the trucking!! so ive been told .
nice photos, its a little unclear in the first photo if that is either compacted fill in the trench or if you are doing it with a horizontal split (which i thought they'd stopped years ago) what sort of realistic distances are you placing a day?
thats all original ground on the left side. in the 1st photo you see that white line on the right is a buried 42" no-joint pipe. the 36" we are putting in is designed to run alongside it. we usually pour a thousand feet by noon if we start pouring right at 7:00am..thats 36"
That is awsome . Very neat work too . What happens when the ground settles or swells with rain etc can the pipe break ?
That really is interesting, I have never seen anything like that before, reddot. I was wondering that too, Iron Horse, how flexible is the pipe for movement? Rn'R.
i can have a rough go at answering this, now that i've read a bit thus making me the most dangerous of fools - one with a little knowledge now lets see how big and idiot i can prove myself.... there are a few critical issues in the prep work, the soil the pipe is being placed in needs certain compaction standards plus the overburden has to be compacted to 24". depending upon mix, they can backfill at 48 hours plus. when the pipe is laid the tech stuff i read suggest covering it pretty well immediately with thin plastic then once the forms are removed and the mix firm enough 6" of soil in order to minimise drying. tho maybe these days they spray it with something instead. the mix used is necessarily pretty thick tho it'd be hard to beat the 20mm slump stuff we used to handpour the entry/exits on the gundagai bypass - you could've work that stuff in thongs (the thongs you put on your feet that is) by the time the backhoe had spread it out a bit for you. we were supposed to hand screed it to the same std as the paver prodiced on the freeway and we weren't allowed to add anything like water to it to make it easier to use. i assume those are the forms showing beside the machine, removing them must be a whole lot of joy...
I learned something in this thread. That's why I love this forum!
They don't have to worry about freezing there so I don't think that movement is really a concern there. Unless we start talking earthquakes. Mouse, What kind of job was it that they wouldn't use a plastisizer or a chemical like that? We had a product that we refered to as Super-P, I think it was something like 15 liquid ounces per yard, we had a separate pressurized tank on the trucks that we put it in. When we got to the job you added it to the concrete and mixed it for 5 mins. for the first yard then 1 min for each additional yard. We would start with a 1 1/2"(38mm) and after the 13 mins we would have around a 7 1/2"(190.5mm) slump. We would pour it then 45 mins to an hour later the crete would be back to a 1 1/2". We used it on state jobs mostly, because of the water restrictions on those jobs.
it was for a concrete highway, the mix was mainly anything but cement from memory, flyash was a key ingredient. the main bit was laid by a paver, two layers of about 10" thickness each from memory. we had the contract to do the entry and exit points to this road at that stage i was one of the boys swinging a shovel/screed. they'd mix it in a batch plant, dump it into a 8 cubic metre tipper then drive it to us, a distance of about 3-4 miles. natuarlly that trip brought a bit of slurry to the top, they'd then dump it in a pile, a backhoe would spread it then we'd work it. as for plasticiser who knows, this was the late 80s and may have been due to cost or lack of said plasticiser at the time. was certainly one of the more interesting placement jobs i've done tho. at all times we had an inspector watching us to make sure we didn't add anything to the mix. the air temp at that stage was up round the 90-100f mark to make it even more fun. oh yeah they tested each batch and if it was more than 20mm slump they'd reject it, half the local town suddenly had new concrete everywhere... all good fun, a bit of work never hirts anyone...