I'm modelling a chamber in STAAD.pro. It is a symmetrical cruciform shape with symmetrical walls with 8 pinned supports in a symmetrical arrangement. I have not applied any horizontal loads to the structure, only vertical loads on the slab (and no self weight on the walls).
I have applied a...
We're designing a piled tank for a sewage treatment works to Eurocode 2. The slab needs to be water retaining so thermal cracking is an important consideration.
Can anyone offer any advice on how to estimate the restraint factor (R) due to the piles?
I have come across 2 methods:
Work out the...
I'm working on a project where we have lots of sites which require additional 300mm dia. ducting installing (for gas extraction). The ducts are generally elevated 2.1m above ground on metal stands to allow people to walk below to access other parts of the site.
On other projects ('designed' by...
Does a 1 degree fall give enough slope for the water to run off quickly enough?
It might be easier to have it flat and let people brush the water to the drainage point if needed?
What is below the structure? Would it be easier to drill holes in the decking to allow water to drain straight...
Are the bolts failing by yielding (suggests a strength issue) or in a brittle manner (suggests a material/fatigue problem).
Have you checked any other connections for problems? We've done a lot of inspections of buildings with cranes hung from the roof trusses, and it's rare that we DON'T find...
We managed to find an access grating near the upstream end of the culvert yesterday, so managed to get a level in the end.
The landowner at the upstream end was refusing us access so we weren't able to get to the inlet. We had seen it from a distance so had an idea of the arrangement.
We are...
jgailla - Some obvious ones which you've probably already checked...
- Is it a circular (not ovoid/egg shaped) pipe?
- Is the gradient staying the same? They are not proposing to relay a long length of pipeline at a steeper gradient?
- Are the materials similar?
Thanks for the replies.
Three of us have crawled through the culvert already as far as we can, up to 80m and have traced the route on the surface.
We cannot get a crawler CCTV camera through the culvert due to the condition (debris, loss of invert). RC car is unlikely to work for the same...
We are working on a drainage investigation, a significant part of which involves calculating the flow capacity of a 100m long culvert beneath a road and some houses to see if it is likely to surcharge.
We want to determine the gradient of the culvert to verify someone else's guesstimate which...
RFreund:
A few example calculations wouldn't go amiss somewhere on the internet to give people an idea how how to do things. Unfortunately I don't have access to the ones I created but might ask an ex colleague if he can send me one.
The most complex one I did was a buried water tank...
I used to use it a lot at my previous job.
The built in forms (UK version anyway) covered most things and the output looked nice. We use CADS Smart Engineer where I am now and I find it more clunky and the output doesn't look as nice.
If we ever had a problem or thought we'd found a bug, CSC...
I think it depends on the cost of the piles - if your piles are very large and very deep then saving the extra pile would offset the cost of the fiddly rebar fixing and slightly more fiddly formwork needed for a 3 pile cap.
If your piles are small then it won't make much cost difference...
BS6399-3 doesn't mention a reduction for asymmetric loading due to snow, however it does allow a reduction in the factor of safety applied to the load (use 1.05 instead of 1.6) when checking member strengths for snow that has been redistributed i.e. blown around on the roof.
The justification...
Is BS4449 for bars and BS4483 for mesh? (I don't have a copy of BS4483)
Assuming ductility is a good thing, then I would read Table 4 of BS4449 as the minimum Rm/Re that it needs to achieve to be grade B500B.
In your case if you have a bar (not mesh) I would grade it as B500A to BS4449...
Thanks for all the replies so far. It turns out that 12mm bolts were specified for the connections rather than nails so this might give enough capacity for it to work as a portal if retrofitted, however something will still need to be done at the foundations to stop the whole structure sliding...
I usually say "it might've worked so far but based on the design code it doesn't so I can't do a calculation to show that it does".
Incidentally, is the 50% increase on bearing capacity in the context of wind loading?
One of the British Standards (BS8004 I think) allows an increase of bearing...
We've been asked to check the adequacy of a timber mountain bike trail currently under construction.
The 'typical' detail is a 100x100mm post either side with a 200x38mm horizontal beam nailed between the two.
Vertical loading we can probably demonstrate by calculation that it works, however...
Sometimes I do take it into account if the design detail means the compression zone could be compromised in some way (for example the top of a reinforced strip footing where the contractor is likely to allow it to be exposed to rain before it has set).
Normally I don't take account of it.
