I am working on verifying initial facing design for a soil nail wall. I am using FHWA GEC 007.
My Design Parameters:
hi= 6"
Sv=sh=5'
WWR= 4x4 W4xW4
2 #4 Waler rebars
I am looking at the following equations to calculate the bending resistance
mvm=avmfy(hi/2 - avm fy/1.7/f'c)
I get values...
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I came across SAS dialogue, and I am trying to understand the difference between nominal diameter and maximum bar diameter, can anyone shed some light please? I looked up the definition of nominal but couldn't find any sources. My thoughts are that the maximum bar diameter is...
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Again I am asking about creep and shrinkage. I have been doing some research to be able to understand why as time progresses, my moment demand increases tremendously.
I am working on the widening of a 4 span precast prestressed bridge with cast in place Deck.
I am using CSI...
Hello, I am working on a precast bridge where there is continuity provided across the slab. I am checking the stress at top of the slab as part of service limit check. I noticed at the supports I am exceeding the 0.19sqrtf'c. I have been thinking of possible solutions such as jacking the...
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I am working on a bridge design where on one pile I have a creep and shrinkage of 500 kip and I want to know if this is a reasonable number. What I mean by a reasonable number, is there a standard of how much typically creep and shrinkage should be?
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I am running a moving load on precast concrete bridge. It is simply supported bridge, so I should have zero moments at the end. This is satisfied when I run my dead load. However, when I run my moving load, my response is different and there is moment near the end. I explored...
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I am currently modeling soil interaction via sap2000. I have the PY curves and I converted them to FD. They are the same as I am using a trib length of 1 foot and the pile increment as 1 foot. my confusion is assigning line springs to pile frames. For example the first link has...
Hello Everyone, I am using CSI Bridge and I noticed that the program automatically assigns end length offset. Is there away to control it? I know I can manually change it but the issue is when I update the bridge model, it resets itself to what was automatically assigned on the first place. Have...
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I am currently modeling a precast prestressed I girders. I noticed that CSI bridge add tendons in the tendon layout data as part of the frame components which is different from assigning prestress tendon. What is the difference between both?
Thanks!
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In one of caltrans bridge standard details, they are providing (2) 90-hooks. I am trying to figure why they did that? I looked up online details for a similar concept and usually one hook is used. Would anyone know what is the concept behind it...
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I have a silly question but it is sort of driving me crazy which is determining roof dead load of steel structure.
Back in college, they will say DL= 12 psf for example. However in my case, I am trying to determine this dead load when I have steel deck and steel frame. My steel...
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I am working on a back to back mse wall design. I read Berg explanation of the behavior of back to back mse wall for two cases. I am having some trouble understanding the effect on the active wedge. It seems from their explanation that if an active wedge is not fully developed then we...
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I am working on MSE wall design and I am looking at soils report. They gave me the type of soil, its unit weight, friction angle and cohesion. Here is where I am having a problem, is that under friction angle they just put (-) and under cohesion is 2000 psf. Does it mean the...
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I am designing an MSE Wall using FHWA as guidance. In one of their examples (E4-12), to calculate the pullout strength, they are using horizontal surcharge. This surcharge they got it thorough the equivalent height of soil for vehicular loading which is 2 feet. However AASHTO...
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I am trying to understand how to determine which direction the corrugated steel deck should span? I looked up online but surprisingly there was no info on how to determine that. Would someone kindly help me?
Thanks!
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I am currently running a response spectrum analysis on a bridge model built on drilled shaft. The way I modeled the piles, is divided into 5' frames and assigned a line spring to each one. I had already calculated the PY and imported it into CSI Bridge.
However I have two...
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I am trying to add Wind Load on my bridge using CSI Bridge. I have defined the wind load patterns; I also tried Bridge Wind loads under bridge object.
Still I am not getting any response. I thought about applying it using area assign loads, but I am not sure if this is the...
I am currently working on a transverse section analysis using SAP. However I noticed that the shear at the overhang is extremely high and I checked my loading many times. I guess my question, does AASHTO provide guidance for transverse shear design? I looked up couple of examples and I noticed...
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I hope I am posting my question in the right place.
I am solving a problem in Linderburg for reinforced concrete slender column chapter. He is using in one of the questions a two way slab- t beam with the effective flane width unknown. Per aci 8-11, the effective flange width...