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Recent content by BridgeEI

  1. BridgeEI

    Cross Hole Sonic Log Testing of Drilled Shafts

    Our DOT does every sixth shaft, but has a minimum they will do per bridge. Same with retaining walls. I thought the feds were requiring it on each bridge, especially when I was first introduced to it.
  2. BridgeEI

    Pedestrian bridge vibrations and the AASHTO pedestrian bridge specification

    You state that this is a signature structure so I assume it’s going to be a fairly expensive structure to begin with. If you’re only talking about adding more structural steel, how much are you really increasing the cost of the structure compared to the overall project cost? I would lean...
  3. BridgeEI

    Brick Manhole Design

    Thank you for the paper. I’ll take a look through it. I’m pretty much taking the stance that WARose stayed and just cram standards down their throats. It’s frustrating when you receive comments like this from reviewers who won’t use any common sense...
  4. BridgeEI

    Brick Manhole Design

    Rectangular. It would be simpler if it was circular since hoop stress is what you would be looking at.
  5. BridgeEI

    Brick Manhole Design

    I am looking for some references regarding the design of manholes that are constructed of brick and mortar. I have a reviewer who is asking for documentation that an opening which has been plugged with brick and mortar is capable of handling the lateral force from the earth pressure. I’ve tried...
  6. BridgeEI

    Help with ASTM C1577 Precast Reinforced Concrete Monolithic Box Sections....

    You can always design it for the loads if you want to, but the issue with AASHTO is that it doesn’t describe how to design for seismic on culverts. There’s a NCHRP report that kind of explains seismic design but it’s very cumbersome and it’s mostly trying to address racking in the culvert. I’ve...
  7. BridgeEI

    Help with ASTM C1577 Precast Reinforced Concrete Monolithic Box Sections....

    Underground structures are not designed for seismic forces unless they are crossing an active fault line. This is all per AASHTO LRFD.
  8. BridgeEI

    Unbraced length of Top Flange in Steel Tub Girders

    Unbraced length is found in the “Case Data” section after the analysis is completed. You have to scroll for a ways to find it. There’s also another spot but can’t remember where. Unless your horizontal brace sections, I’m assuming tee sections, are rigid enough to laterally brace the top flange...
  9. BridgeEI

    Scrapers and off road haul trucks on new bridge

    Several of the OL-1 trucks are near 200kip so I bet it checks closer than you think. Is it a 1 time thing or using it as the main movement from one side to the other? If it was unloaded and a one time deal I think it would check. But I don’t know particulars on the span etc so hard to say. I...
  10. BridgeEI

    Has anyone lengthed an existing bridge?

    That’s a pretty good idea but how would the contractor you’re dealing with handle it? In my area, they for sure would put the bearings down before casting the deck, more so out of habit. What are the grades on the bridge? Can you jack the bridge up 6”, or some distance, and do everything else...
  11. BridgeEI

    Has anyone lengthed an existing bridge?

    What if you milled 2” off the deck, did your extension, then did a 2” concrete overlay to profile the deck so you didn’t have a sag? You could even get survey shots on the deck before profiling to see if it was even going to be an issue. Im with you though. The only other work around I’d have...
  12. BridgeEI

    AASHTO Pedestrian Guardrail Service Load Combination

    HotRod10 - I’ve always factored them but I see your point. My argument would be AASHTO calls it a “design truck” and we factor it. It’s vague enough I could see the argument either way. BS2 - As a FYI, if you look at 3.4.1 it gives a description of each load combination limit state and what...
  13. BridgeEI

    Cost of jacking a 10x4 box culvert

    Just a thought, but have you looked at laying back the slopes or trenching? Depending on your situation, it may be a significant amount of earthwork but could be cheaper than the temporary shoring options. Obviously you have site constraints we’re not aware of but wanted to throw that there.
  14. BridgeEI

    AASHTO Pedestrian Guardrail Service Load Combination

    Agree with bridgebuster. If it’s concrete you would need Service I for crack control or if they’re asking you to check deflection. Other than that you should only need to check the combinations bridgebuster suggested.
  15. BridgeEI

    Cost of jacking a 10x4 box culvert

    I think your price is in the ballpark for pipe, not including cost of the pipe. We tried something similar on a design build and the contractor said no way to an RCB that was a similar size. They ended up doing a cut and cover instead due to cost alone and that was with a mega interstate with...

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