ToughButterCup

Yes but in this video, the wheels stay firmly on the ground: Another case of 'Tinternet a place of shared ignorance' eh?

Well now, @IanR, have a leedle look at this then

This here piling mat that I'm sorting out needs to be tested with a plate test. And to do that I need an 8 ton reaction load. Following the by now normal steeeeep learning curve I learn from some that it is common to use a loaded 20 tonner's back axle, from others that I need a dead weight, like a 10 ton digger (no suspension). Where do I get a 'dead weight' 8 ton reaction load? (Keep it clean, please @Nickfromwales @ProDave) If I have 32 tons of lorry parked on my piling mat, and the test plate and hydraulic ram is put under the back axle, won't the test rig merely tend to jack the lorry back off it's suspension system? And thus invalidate the test? Here's an example of it done with a wagon (sprung) And here with a digger (unsprung) What I want is Vorsprung durch Technik, fellas! And it'd be good if I knew the right Technik.

Oh how I have come to agree with you: painful. A thorough check of an Invoice against the relevant counter dockets with my local BM showed an error - of £15 in my favour. It could just as easily have been the other way round. And I have only checked a small sample. I had become sloppy at keeping the dockets and then checking them against the invoice. All the dockets are hand-written - sometimes so sloppily that I once remarked .... 'I'd love to meet the person who taught you to write'. Not joking, his writing looked like the scrawl of a drunken left-handed inky parrot. "None of us can read his writing either" was the chorus behind the counter. There's huge pressure on the sales folk to get account customers served and out of the door. They'll never see the hand-written docket ever again, and couldn't care less. It's the folk in the accounts department I feel sorry for. Cash, up front from now on - if the lads at the counter have to look the price up and every one has to wait - well that's the price of accuracy.

Bingo! Even I can do it! Simple things make my day sometimes! Right, can't wait to see that contractor again...... I am so going to enjoy the conversation....

@Onoff, thanks. I'll need that later set of commands later when I get my hands on a copy of AutoCAD. I have DWGTrue View. This appears far too interesting to me to let software do it for me. I'll try steam first and then see if the software gets it 'right'

Whoooaaa! Lots here to distract me from the nitty gritty of the Windows Schedule. Thanks for the excuse.

We are building on a slight slope: I have come to realise that this is a significant advantage in terms of drainage and other issues. Talking to a contractor about how much stone will be brought in, he mentioned that it was something of an art to estimate the amount of stone needed - especially where there's a slope. From my teaching background I know that conservation of volume is one of the last things that humans learn (look at the difference in the designs of pint glasses - some look large, others surprisingly small - even experienced people find it hard to estimate volume) We have had a topographical survey. I have superimposed the piling mat area in red. The image is oriented North-South. You will see there's a cross-fall South East - North West of about a meter. And somewhat less from the North East to the South West. Roughly, it's a lop-sided wedge. If it were a simple wedge, calculating the volume would be easy. But it isn't a simple wedge. I frightened myself silly looking at maths websites in attempt to calculate the volume. I already hear a chorus from over the water about over-thinking. This is just a bit of fun. At worst we'll need a few more loads of stone: tough, suck it up. I'm interested in how to go about calculating that wonky wedge volume. Pointers, please!

And here's the briefest, definitive, well-written guidance I've found which explains the issue in relation to self-builders cdm 2015 - qa 3 self build projects.pdf

Yes. It boils down to a combination of price, rig size, and piling design (in terms of kN per pile). Ian

Yes, exactly, you need to go through that exercise. 'Known unknowns and unknown unknowns' (God, how I loathed that bloke) We are on a small, but noticeable slope. That means that we can accommodate all our post-piling spoil. Might that work for you?

No, @Stones, I imagine they wouldn't probably because the mat needs to take a dynamic stress . And the mat needs to be penetrable by the poker (stupid term for a humungous vibrating crane-mounted ramrod)

@swisscheese - have you noticed we are using 'ground improvement columns' NOT piles, but they appear to most people to be piles so we call them piles - in error. Have a look at this However, the piling mat is the same for both: I think. Notice the difference in the calculations for the depth needed if you use Polypropylene Geogrid Tensar SS20. You might like to ask for the calculations they have done showing the difference made by the grid: in our case 280mm instead of 480mm I do not wish to be seen to be advertising. Stone columns and piles are different beasts. Stone columns are significantly cheaper than steel piles. We have about 52 columns to insert. Start 0930. Finished - off site by 15:00 same day.

OK @swisscheese, to help you, I'll go into detail; Here are the calculation for the depths of the working platform thickness provided by TC Vibro (I'm working with Dan and John Ashton the Contract Manager) PilingMatCalcs.pdf The numbers which interest us are the Required Working Platform Thickness (bottom of page 1). There's one for 'raw' thickness of 0.48m and the other for a piling mat with Geosynthetic Reinforcement , 0.30m What constitutes a piling mat if you need new fill? Here's the answer - again from TC Vibro Specification for Upfill Materials.pdf Are there any guidelines for Piling mats? Of course there are. BR470t.pdf In preparation for this exercise we had a topographical survey done (5 locations) soil sampling 5 locations and a site visit done by Dan from TC Vibro. He asked me to dig a three meter hole in front of him so that he could hold the clay that I dug out. He needed that done in front of him so he could judge the water content. The charges for the rig set up are eye watering (£2.5k per visit) but after that each stone column of stone is relatively cheap. As I explain above -broadly- there's probably no need to get the mat tested. But on balance, why would I not demonstrate good faith to the company when they have visited me three times (Dan twice and the Contracts manager once) to make sure the risk of failure is as low as we can reasonably get? I also visited a site on which TC Vibro were working. In addition I have called out the water board to survey the water pipes (compulsory when piling within 15 meters of a water pipe here), but more honoured in the breach than the observance I think. Luckily, our pipes are cast iron, and a meter below ground level. Can I suggest a bit of care with the crushed concrete spec (see the Up-fill spec attached). Dan informally talked me through some of the poor practice that some contractors do in preparation for the piling mat: the end in mind is making sure the piler (or in our case the 'poker') can get through the mat and the substrate. If the area hasn't been dug to the correct depth, the risk increases. @John Ashton, you may want to comment on the above. @swisscheese, I'd be interested in a bit more detail if you can bear it.....

Exactly. What we're trying to prevent is significant deviation from vertical: the mast is huge; the machine has a limited capacity for self adjustment, though. I've got one informal quote of £400 ish, which to me seems cheaper than the price of having a rig hanging around at £2.5k per day. The setup cost of the rig is £2.5k per day. So, were the rig to sink just a bit more than allowable, I would have to remediate , test properly (to prevent the same problem occurring again) and do it all again. Bang goes £10k if all goes well following a cock up. And easily double that with a bit of bad luck. Yes. And I've been to see it in action, talked to the rig driver, the company contracts manager and the young engineer in person on site. Contrary to some views expressed in this thread, getting this wrong would be a big deal.

Nearly right. The piling mat needs to be right for the machine in terms of the weight it will bear. Also the piling mat needs to be at the correct level. Of course there is an element of common sense to be applied here, but the charges that accrue if I get this aspect of the job wrong are £2500 per day. So for the sake of a couple of hundred quid, why risk the standing charge of £2.5k per day while I get the piling mat sorted out. Perhaps you could explain your comment in a little more detail, please? I, for one, am not sure how to read it - yet-.

Just a quick post to ask if anyone knows the rough cost of Plate Bearing tests? SPONS doesn't list it. Whats a Plate Bearing test? Why do I need it? The pilers won't come on site without one; and if you are using one of these, you can see why. All 37 tonnes of it....

Weekend.... photos to follow

I was thinking (after a few beers) of pimping it with LED floods.... I strapped a couple of rechargeable LED floods to the boom: boy what a difference!

See? I told you.....

One way of annoying a newbie digger driver is to give her a digger and tell her to dig a hole in Lancashire: more accurately the Fylde coast. This what you get: A bucket full of clay - that won't come out of the bucket. Try as I might -swearing-shovelling-crowbarring- Nadda. Nichts. Rien. It sits there looking at you. And then you ask on BuildHub how to sort this problem out and you buy one of these bad boys (bad people) A Clay Spade Hallelujah! This happens... And then when you've stopped swearing and start grinning, a little while later you get to find water..... Out comes the magnet and its ................. CAST IRON. Phhhheeeeeww. I was told by those locals who 'know' that the pipe is asbestos. The man from the Water Board came out, looked at it, sucked his teeth, tapped it, got his ray gun out, zapped it, sucked his dentures some more and said. "Tha's dun me job fer me maaaate. Aye, 'appen, it's awreet is 'at. Pilin', it'll be nay borra, 'appen" and promptly left. With the back doors of his van open and all his tools cascading out onto the road. I nearly wet myself with a mixture of relief and laughter Well, that's that one sorted. Next: piling mat.

Just get MrsPeterM to whisper in your ear. You know it makes sense!

They're on sale at our local garden centre. Look, here's one.

Hello Lauren, A good way for you to get members of this forum talking to you to is to suggest a design, and then ask 'us' what we think of it. For example, let's say you want to have a new brick-built extension - or renovate a brick-built wall. Search the forum using the search engine. Read the posts and the links that have already been made. Then, ask about those aspects that you find interesting. So, if you ask about bricks, then as sure as eggs are eggs, @Construction Channel will reply giving you too much detail about (say) the reason why Flemish Bond bricklaying is the best (or worst), and @Declan52 will tell you about how much the foundations will cost, @Nickfromwales will tell you about the best way to install a wet room, @ProDave will help with the electrics, and @Peter M will help with the best curtain fabric. Welcome! Ian