Just wanted to chip in and say great posts here.
If I could add one thing from my own experience, it is develop the skill of being roughly right.
Doing line beam checks, sketching deflected shapes, working out the worst traffic positions by thinking about it.
For me this is critical. Good...
Thanks @Canuck65. It sounds like they will have good control of the process. I've heard of a project where this was overdone and they had to end up closing a bridge because such a large quantity was removed. This must have been down to a misunderstanding of what should be removed.
Hello Everyone,
I have a project where there is a requirement to hydrodem part of a concrete structure to a depth of 4in - section is approx 4ft thick. What I am wondering is if there is a good way to visually see how much has been demolished. I am thinking of something like a marker that...
There's probably many more sensible examples and when you mention bracket I guess you weren't thinking of reinforced concrete but what about an over reinforced beam. It's usually something we look to avoid but if designed correctly(!) then a sudden brittle failure at a certain load is...
Thanks for your time Klaus,
To extend this further, if I have calculated a total strain due to autogenous and drying shrinkage, how do I apply this to a section?
Do I add these strains to the existing strain due to load in the section and check the effects?
Sorry, if the first question or...
Hi all,
How does one consider creep and shrinkage in analysis of a structural element? For example, do you actually check different design stages by adding the strains due to shrinkage and creep to the strains present in the section from loading to increase the stresses?
So, for the long...
Thanks Trenno, that's what I thought in fact and the requirements the same.
What I wonder if there's anything else I'm not considering, I could be flogging a dead horse here...
Thanks
Hi Chaps,
I've designed a corbel supporting a pcc beam using the strut and tie method to calculate the reinforcement requirements.
Any thoughts on checking service conditions in RC corbels- for cracking at the face of the tension tie based on the area of concrete?
I'm not sure this is...
Thanks hokie66. that's useful to know. And you are quite right, the orthogonal reinforcement is enough to handle the openings.
And regarding the upstands, and framing back to supports. The other openings in the slab either have one edge along the precast beams or quite close to the outer...
Thanks for the replies chaps, really helpful.
The figure of 30kN/m^2 is right in the worst areas of the slab under certain conditions- i.e maintenance equipment and cranes. The figure does seem a bit high but that's what has been used so for now I'm going with it.
The wheel loads are...
JAE, you're right, nowhere near that! I horsed that up not you. That value from the previous issue of the loading they made but it was amended in a later issue.
It's more like 30kN/m^2 in the worst case. I already made a finite element model in fact so I'm glad you thought that was the right...
JAE, sure thanks for the reply!
1. It's spanning over air/ or sewage, it's a drop shaft for a combined sewer overflow.
2. there's permanent loads of 40kN/m^2 for the permanent condition and in the maintenance condition it has to support some equipment and crane wheel/ outriggers, so, more like...
Hi,
I'm undertaking a design check for a large 12m diameter cover slab. The slab has a number of large openings(2.9 x 2m the largest).
What I'm not sure about is how to determine the reinforcement at the corners of these openings, I see the practice is to provide diagonal bars but I'm not...
Chaps, thanks for all your replies.
The biggest impact for me is correcting the assumption that the bracing is unloaded thermally. It was always my thought that the reduced forces this gave were due to allowing the bracing to move as well when loaded thermally.
THLS I think your point about...
Hi all,
It's been proposed on a project I'm working on to land the base plate for a new steel structure onto an existing masonry abutment and connect in to the abutment by drilling into to the masonry, grouting in a dowel connection and the tensioning the bar after the base plate is installed...
Lomarandil exactly right, the oversized holes are to allow tolerance at installation. Yes, totally makes sense. Thanks for your time and explanation, it has helped me as well.
SlideRuleEra Thanks for the reply. I understand what you're saying about the bracing temperature, it makes sense now.
I see so, in this case the differential between the main structure and the bracing elements could be too large? +40o C. on structure and 0o C on the bracing elements. So...