|Michael Gilligan||03/12/2019 23:01:44|
15455 forum posts
With the festive season fast-approaching, I thought it time to revive an old Chestnut: Here is an example of modern work
Seems pretty unambiguous ... but feel free to discuss.
|Mike Poole||03/12/2019 23:05:53|
2538 forum posts
Theoretically incorrect but seems to work.
|991 forum posts|
Weird looking. Why the huge tubular spacers?
|Michael Gilligan||03/12/2019 23:16:11|
15455 forum posts
I think they are long nuts ... suggesting, perhaps, that they are done-up very tight.
|Henry Brown||03/12/2019 23:21:24|
187 forum posts
I wonder if the longer hex parts are attached to the spreader plates, the hex is used to stop the spreaders turning as the nuts are tightened?
1075 forum posts
I wonder if they are counter-bored, but with a "Normal" or "Heavy Nut" thread length.
Hence the top one with the circular spacer, as the stud was even longer.
It might allow them to be torqued up correctly whilst ensuring the shear load is on the parallel section of the stud, rather than the reduced area of the root of the thread.
Edited By peak4 on 03/12/2019 23:57:52
|Mark Rand||04/12/2019 00:11:13|
|874 forum posts|
Seems perfectly correct to me. The lock nut is of a smaller thickness and on top of the main nut.
|Michael Gilligan||04/12/2019 00:48:18|
15455 forum posts
I should mention that the green brackets support a substantial tubular ‘bull-bar’ to protect the concrete bridge from impacts by high vehicles.
Credit Google Earth
|Speedy Builder5||04/12/2019 06:40:17|
|1981 forum posts|
I wonder how far the anchor bolts went into the bridge ? Did the top bolts hit an impenetrable object that required an extra spacer under the nut? Looks like a good installation to me. Enough to take the top off a double decker bus!
17828 forum posts
Top one being into concrete may have hit some rebar so did not get drilled so deep hence the packer., I would expect them to be resin anchors rather than sleeve or expanding type. The middle one is not placed that well being in or close to the junction between brick and concrete.
As to the nuts that's simple the guy could not be bothered to shorten the threads so just popped some jointing nuts on first as he knew a model engineer would soon be along and not be impressed if he had too many turns of thread showing above the top nut
|Ian P||04/12/2019 07:32:20|
2352 forum posts
If the bridge in the Google Earth picture is the same one as the one in Michael photograph then the bracket looks to have been modified or altered at some stage.
In Michael's picture there are 6 fixings to the masonry but there appears to be 8 in the second image.
17828 forum posts
Ian, I think you are seeing 6 fixings but the top ones into the concrete have a rectangular "washer" not square like the lower 4
|Mick B1||04/12/2019 07:39:35|
|1545 forum posts|
If it'd been me, I'd've found it hard to walk away leaving that bottom right square washer - if that's what it is - visibly on the skew.
Edited By Mick B1 on 04/12/2019 07:40:33
|John MC||04/12/2019 07:44:07|
273 forum posts
|Brian H||04/12/2019 08:22:40|
1569 forum posts
I suspect that is because the thin nut should go on first.
It looks as though the end of the thread has been hammered over to prevent removal.
Edited By Brian H on 04/12/2019 08:25:03
4389 forum posts
OMG but the bridge men have put the thin locknuts on second, following the practice of engineers and fitters throughout the 19th and 20th centuries on applications such as big-end bolts on large marine diesels and before that steam engines, instead of adhering to the 21st Century ISO standard ( section 5 of ISO 898-2: 2012 Mechanical Properties of Fasteners made of Carbon Steel) of putting the thin nut on first then the thick one. The science of which is outlined here **LINK**
Science deniers, that's what them bridge men are. Next thing they'll be telling us climate change is a hoax to institute a one-world government. Somebody alert the authorities at once, before the bridge collapses and kills Santa Claus.
Edited By Hopper on 04/12/2019 08:28:10
|derek hall 1||04/12/2019 08:28:00|
|70 forum posts|
One of my main gripes is studs that have a foot long of thread poking out the nut.
You see a lot of this in modern construction, an example of this is when stuck in traffic on a motorway with nothing to do and looking at the way the overhead gantries are secured to the concrete mounting blocks.
I haven't got a photo, other drivers stuck in the traffic alongside me might wonder what the hell I am I taking a photo of !
|Martin King 2||04/12/2019 08:34:34|
|680 forum posts|
In the spirit of Xmas, are these technically known as walnuts?...........
Getting my coat..... Martin
|Martin Kyte||04/12/2019 08:50:22|
1781 forum posts
Are they not on the bridge wing, so they should be wingnuts?
|1615 forum posts|
Does anyone know the actual result of a tall and heavy vehicle hitting the bull bar at speed?
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