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Hello, I'm unsure of how to interpret the design forces for the bridge deck overhang. It says to design for the transverse or vertical forces from the impact table (Design Cases 1 and 2). But it also has a section about calculating the forces based off of the railpost capacity (but it also says...

Would uplift forces not count as a reaction on the bearings or piers though?

One thing is that when looking at the shear in the girders, you only look at the single design truck instead of 2. Another question is it also mentions putting the trucks in adjacent spans to produce maximum force effect. What about when looking at any uplift forces? For a single bearing this...

Hello, AASHTO has a clause where you consider 2 design trucks at 90% weight with a spacing of 50 feet between them for negative moment and reaction at interior piers. When they say reaction at interior piers do they mean to include the bearing in this case as well? It just mentions the piers...

Hi, I'm unsure how to calculate the area enclosed by the shear flow path for a concrete I-girder. Would this just be the area of the girder itself?

Hi Everyone, For determining the forces in a steel girder section with a concrete deck from a modelling program under different conditions, is my interpretation below correct? Before the deck hardens, all these forces are assumed taken by the girder only and is modelled as just the girder...

Hi Everyone, If I have a connection at a gusset plate as shown below, where the entire connection is welded, would the unbraced length of the bottom member be Unbraced Length 1 or 2? I would assume the connection would help prevent some out of plane buckling. Thanks

From the old thread there seems to be a lot of differing opinions. Seems like you could treat it like an anchor rod/bolt connection at the top piece. I was thinking that in this situation if you had 2x the required development length into the bottom pour, then both tension bars would more or...

If I am designing a retaining like shown below, how far should I extend the upper layer of rebar into bottom section to ensure adequate development and load transfer between the tension steel in the two sections? Would 2 times the development length be required? Thanks

No as in it is an issue, or no as in it isn't an issue? Basically it is repair work where some geometry is changing and existing bars are in bad locations. Seems like it wouldn't be that different to the scenario below where you have two layers with splices occurring at the same point.

Hi Everyone, Design Codes allow a non-contact lap splice of up to 6". Would there be any issue by having a non-contact splice take place vertically instead of transversely like shown below? Provided that the section capacity is calculated assuming the steel is of the lower depth/

SlideRuleEra (Structural) Essentially the existing splice location wasn't in the spot that was shown on the original drawings. So the new bars that have been fabricated and are being spliced onto them have a set length. So if the layout was to change like you have shown, the one lap would be...

Tomfh (Structural) The smaller lap length is the required length. The bigger one is just extra and is to avoid having to unnecessarily cut rebar to match the smaller length. HTURKAK (Structural) Welded splices aren't permitted in this application according to the design code.

Trying to avoid having to use mechanical splices for ease of construction.

Correct, this is a restoration project so I am kind of stuck with the splices where they are. As for the blue and red splices. Both are correct (blue length is the one required, red is just extra length). The red splice could be shortened to the blue splice length, but I want to eliminate...

Hi Everyone, Due to the existing conditions the reinforcement needs to be spliced as shown below. Is there any issue with the splices looking like this. I don't think so, since all the lap lengths are adequate for full development, but just wanted an outside opinion. Thanks

Hi Everyone, When using skewed reinforcing to calculate flexural capacity the codes don't really give a guideline about taking into effect the skew of bars. I'm assuming you can look at the problem using basic Trigonometry in the example below. Would the assumption be correct that if I am...

I would have assumed a non 90 degree angle would have some effect as a portion of the radial tension in the transverse bars would have both a vertical and horizontal component. But then again, my thought is they cross over such a small area it is negligible.

Is that mostly because the longitudinal and transverse bars intersect each other over a very small area relative to the splice length? i.e still plenty of concrete flow around the rest of the spliced area?

Hi Everyone, If I have a longitudinal layer and a transverse layer of bars that are not 90 degrees to one another, does it affect the required splice length. In the first picture below any affect of the bars 90 degrees to one another is ignored, but what about the situation in the second...