Search results for query: *

Thanks @KootK, we will still need the outer stiffeners during the jacking operation, but agree with the rest of your comment. I'll investigate these tension field shear design and web doubler plate options too.

@Eng16080, will definitely consider just increasing the section size, agree that is probably the easiest solution in this case

I have a situation where we are using a grillage of steel beams to temporarily support and jack up another structure. There are separate jacking points and packers along the cross beams; when the jack is at the end of its stroke length, the load will be transferred to the packers and the jacks...

Does the design still work with some of the bars cut off? I have run into this situation in the past, where (usually luckily, but sometimes deliberately at design stage) we could afford to lose a few bars - either having insufficient development or cut off completely.

We have used this recycled plastic stuff before as kerbs on boardwalks / golf cart bridges, similar to the below photo. I have to admit I don't really recall how strong the stuff is, but in those cases the loads were very small. I've also seen them used as pedestrian barriers, fence palings...

@human909 You're correct that the whole point is to not engage the bolts (ideally). However, in the temporary situation before the deck is cast and the splice bolts are properly tensioned, we are looking at the option of these loosely installed bolts providing restraint to the girders mainly to...

Thanks all for the replies. I just wanted to respond to a few of the general questions in this thread. The reason for this particular installation sequence is really not part of my review, I am only checking the temporary condition of the girders during construction. There are a few additional...

I suppose attacking this from another angle - if these bolts are installed snug-tight (i.e., by the usual definition, installed with a spanner with the full force of a person) instead of hand-tight, is it realistic to expect that they would allow slip in the connection and to avoid loading up...

Are there any situations in which hand-tightened bolts (less than snug tight, basically loose) can be relied on for structural capacity? I am checking a steel-composite structure which is intended to be continuous for the future live loading. The beams are initially to be installed in a...

Not quite. I think you can assume the cog/hook provides an immediate 50% anchorage which might be enough capacity in some cases. It depends on how the code is interpreted, whether the use of a cog/hook means the development goes from 0->100% from the end of the cog/hook to the point of 0.5Lt...

This is a problem I've come across in similar situations to your sketch. AS3600 only requires that the tie extends beyond the node to achieve the design strength of the tie, not necessarily that it is fully developed beyond the node. It also says that you can get away with a minimum of 50%...

@Once20036, I'm confused about what you mean by the sides being non structural welds? Agree that the unstiffened mitre joint is not ideal but it can be made to work in some situations. The usable capacity is something in order of 1/2 of the bending capacity of the hollow sections themselves...

My last post on this because I don't want to clog up the thread with my ramblings. I've tweaked the model somewhat to reflect the more realistic geometry: *80' span *7' width *5' height *Top chord = 3" tube (generously assumed to be 0.25" thick, which seems to be the thickest available)...

Also, I initially thought the 73' span by Sym P. le seemed a bit long, but it seems to be closer to 80' even. The height of the doorway should be 8' exactly, given there are 16 slats at 6" spacing as can be seen in other photos.

Scaling off some (kinda) known dimensions, I agree with SWComposites, these are smaller than 4" tubes, they appear to be 3" instead. The width is also around 7', not 8'.

3DDave, I think the bridge would be flexible enough in torsion that it could just twist slightly and find support on 4 corners again. That's just my guess. From what I have seen, it is very common for pedestrian bridges with ~20m/60' spans to have a top chord of a 150mm/6" or even 200mm/8"...

3DDave, it makes some difference, that 2.5 factor goes down to 2.3-2.4ish.

I ran a quick model to see what the difference would be for the two load patterns. The case with full live load on the entire bridge is the worst case. I made a guess at the dimensions based on the photos: *Span = 60' *Width = 8' *Height = 5' *20 bays *Top chord: 4" aluminium tube *Bottom...

Interesting thought from reading the comments... Is there any situation in which a pony truss like this has less capacity with 50% live load distributed on one half vs 100% live load applied everywhere? My instinct would tell me no, but I would be interested to muck around with some simple...

KootK summed up exactly what I was thinking. Assuming it is a T-section, if the loading is on the web, then there would be a tension component transferred to the flange so that the two pieces deflect the same amount. If the shear connectors did not have any capacity to carry tension, then the...