R & R warehouse floor

oceanobob said:

when the rebar gets bad and circumstances allow, we have been running the aggressive diamond blades and cut it up in manageable pieces....diamond blades cost vs other costs and is more expedient and predictable. That job looks involved due to the size as well as other reasons. Did you have to change that channel? We always have a hard time with the handheldsaws on a wall horizontal cut and we dont have a wall saw - the saw specialists exact a toll on the wallet for their wall work

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We had to do some cutting with the hand saw but just stuck with an abrasive blade, also had the 120 with a breaker on it for the majority of the work. I also used the breaker on the face of the wall 8" thick I think.... but what really slowed us down was the 5 filled in docklevelers you can probably see where they used to be in the pics, when someone put them in rebar must have been cheap because they used plenty... same with concrete it was well over a foot thick a their bases and a good foot thick all around the perimeter... and when they filled them in they used more rebar and filled solid with crete!!!

This was a complete demo so no changing the edge The edge of the dock wasn't too bad I think it was 6 x1/4 or 3/8th angle and they plug welded anchors every foot or two but once you put the hammer behind it or even on it it popped off pretty easy

I hear ya' on the saw guys, we sub a lot of wall and slab work out for door cuts on these tiltup's... have one of those stihl ts512 on the little walk behind cart I use for floor cuts up to a hundred or three feet it'll go 6 inches with the 16 inch blade on it but it's a lot slower then a real saw

The trucks are over the road units and they can pull up with 65k and pick up 4 pallets of produce to complete the load....they are backing in and not really going fast but the weight just hammers the bumpers - in the pic you can see a bumper, the bi-fold leveler ramp, then the other bumper. The action of the truck does indeed impart a rotation onto the channel which is why we weld two rows of welding rebar at 12"oc. Will add a pic when we place the channel.
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Concrete around dock pockets can be inordinately thick because of many reasons: the grade tends to slope toward the depression or someone changed the dimension for the pocket and they left the grade low or an engineer wanted bolts of some long length so had to be thick or they didnt have an engineer and "threw" concrete and steel at it.

As to cutting, we also have a two cycle saw -a Stihl TS760 (factory fitted for 16" blade) which I bought new a long while ago and is showing some signs of age: carb manifold bolt fatigue crack, blade bearing growling, belt loosens etc. I am getting better at fixing it. Their new saw is the TS800: I bought a 'beater' TS800 from C/List and the power curve is improved (less peaky). They changed the cart so the old cart wont work. Another lark deal: also long ago I had fortunately bought an older at the time 14hp Kohler powered Target saw and it was self propelled and that made a huge diff in the pace of the work and the life of the blade. The motor carb is calibrated for the old school volatile gasoline fuel and the ignition is weak and it is hard to start via a rope start ....so I looked around and found a newer 20hp saw w electric start....also self propelled and that saw runs smooth and takes big cuts.

Same thing with the warehouses we work at, a large portion of the trucks coming in are straight from the port or rail line so the cans are at max gross and sometimes more and there are quite a few drivers that don't know how to slow down before they hit so it just kills these bumpers. the different warehouses have been trying a couple different new style bumpers so we'll see how it goes but anytime you have that much mass being dissipated so quickly I don't think they stand a chance... especially when it happens several times a day

We also looked at a job a while back that a lot of the steel edges are failing on the warehouse doors, they have 4 x1/4 inch angle iron with what look to be #5 bar welded every couple feet into the 'v' of the angle iron and was wet set into the floor when they poured it... from what I can tell the damage is coming from their dock plate they use with the forklifts, every time a lift truck goes across it the center supports hammer the top of the steel edge and concrete because it's only the top concrete that's separating not the face of the building... will be interesting to see what happens if they give the go ahead on the job as I already figured we'd have to remove a few feet of concrete behind the door and down probably a foot -- of course if we're doing that then it isn't much more to put in a dock leveler oh well... guess we'll see sometimes it can take years for the powers that be to make up their minds on what to spend where.
The only trucks that back into these doors are hauling brown cardboard boxes that get distributed to amazon fulfillment centers and they all use those regular portable dock plates.

That angle in the process of falling off is sure discouraging - but those forklifts work the heck out of the concrete.
The pics show how we had to weld the rebar through the channel and we did two rows. I was reading on some federal highway publication that dissuaded the use of a bent piece of rebar with two fillet (j groove) welds to hold the 'tang'. Apparently this method allows some miniscule motion whereas a straight through rebar connection does not. And I use the old standby: 7018


When I buy rebar for welding, I always spec Welding Grade with the W stamp.
We also coated the inside face with that epoxy made by Sherwin Williams called macropoxy.

A few more rebars to tie, then a shutter with a cant under the c channel, and we are ready for concrete.

I can see where a through piece of rebar would be stronger. The rebar would have to shear through instead of just a weld.

Nice work Bob!

The concrete mix was 4000 in 28 days, had 5.5 sacks cement, 0.5 sack of flyash (about 9%), aggregate is "blend mix". Blend mix means we add a little more aggregate from the 3/8" plus bin in addition to what is already in the 3/4" plus bin. This material has to be boom pumped or line pump with min 3" hose. Finer aggregate concrete is not a very good solution for commercial/industrial and forklifts which are the nemesis of decent concrete.
Forklifts were permitted to drive across the patch slab within three days of placement because we kept the water out by using a high range water reducer and the temps are warmer.

About the welding and the dock levelers and the trucks....we waited about 2-1/2 weeks for higher strengths and concrete to dry out so we could weld onto that channel which is intimate with the concrete. They would have liked it done sooner but the business typically doesn't get crazy busy until the first/second week of July. So yes, they were quite glad to have another dock for the trucks that are hauling off the produce.



The dock leveler at bay 3 hangs a little low: it needs a spring on the knee to be adjusted. Moving these things and aligning them on the forks prior to positioning is nerve wracking - for sure finger pincher stuff - because they will quickly flop (the thing is a giant three piece hinge but with a knee - to operate, they pull up on the second 'fold' or stick a pipe in order to lever it into position ... the knee flips into position and the outer segment kicks out and lands on the truck....when the truck pulls away, it fall to the hang position). Not for the unaware to handle these.

Good ole Powcon and some 7018 Excaliber stitched it onto the channel.

While we were there, got a chance to practice some flame straightening but elected to invoke a modicum of restraint since the plate is kind of a free from object - thus the bowstring chain and binder. The flame straightening method involves rapid heating then cooling in order to astutely shrink the metal on one side but not the other. The pattern and the heating time is critical and the piece is best brought back to dead cold before the next attempt, none of this was a issue as we had plenty of jobs ..... heat and water cool a couple times, then let it rest. The flame straighteners supposedly can accomplish this and work miracles. Neophyte at this: we typically had invoked brute force or redhot with a torch.



That piece had big warp on the one corner and it is pretty good now. The process admittedly takes some patience - sometimes think I might be heating too much: have to get a temperature crayon to try and determine temp achieved and learn how fast to move the rosebud. The rosebud is pretty good sized and I recall having to get a larger acetylene in order to provide the draw rate. Supposedly should be able to perform this task without heating higher than a dull red color which quickly fades once the torch is removed. Rapid cooling with water is intended to gain the maximum shrink - notice the wet concrete in the pic.

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All cleaned up and ready for trucks.

Look into changing over to propane for your rosebud. If you find a LWS who knows there stuff a propane rosebud of the same size as an acetylene one will give you about 3 times the btu's. I use propane for heating as it is much more efficient.

My original reading about Flame Straightening is from the Lincoln welding book (that big thick book). It describes methods to develop a sharp difference in the heated vs cool areas. I recently obtained two more texts: one that has a chapter on this topic and then I also got the book Flame Straightening Technologies.
It appears the use of a rosebud can be improved by using a cutting torch tip due to the heat intensity (more focused). Maybe will start a new thread (if) as I make progress with this topic.

A heavy beam clamped/tacked underneath, some heat and a couple big Bessey clamps would work for straightening a plate like that too. Applying the heat from the bottom would make a difference too because it will pull more to where the heat is concentrated when it cools.

I've seen a few of these dock seals getting ripped off by truckers lately... and they aren't even very old??? either the truck drivers are getting more aggressive or they have found a new way to backup!!! These things used to be just about bulletproof until the wood frame rotted!!!


Also pulled off a bunch of premade Frommelt side bumpstops cause they were replacing them with 'better ones' heh heh we'll see how long the new ones last

Durn Trucks … I had a problem of the trailers tearing the rubber stop pads off the docks. Figured out the real problem was our OTTAWA Yard truck. It had a hydraulic 5th wheel. With the trailer against the rubber stop, when the OTTAWA either lifted or dropped the trailer, it acted like a crowbar. Solved the problem by covering the rubber with metal plates. The trailer then slid against the metal clad stop, instead of tearing it off the wall.

Without the rubber stop, the trailers beat the dock edge to bits.