Hello,
I am putting a calc together for a conduit hanger where the conduit are fitted b/w W beams as shown. Flanges will have a notch to accommodate the conduits for snug fit. Can someone point me as to how I can find the capacities of W Beam with a notch in flange? The beam will bent about...
Hello,
When analyzing a simple span bridge (Fixed bearing at one abutment and expansion bearing at other abutment), would I assume for all the temperature movement be taken by the expansion bearing and hence no force traversed down to the abutment piles of fixed bearing?
I am computing loads to...
@HTURKAK
It is a 9" concrete deck and the girders would be supported on the elastomeric bearing. Please see attached reference for a similar bridge. https://files.engineering.com/getfile.aspx?folder=b92b2ead-e9a5-4773-bcfd-36da28fddd99&file=Capture2.PNG
I am unclear on which options to choose for design of a pier column. The pier column will be between a pier cap and drilled shaft. The length of column is about 26 ft. My understanding is it will be a sway frame in y axis for sure but not 100% clear on x axis (y being the axis parallel to bridge...
I am unclear on which options to choose for design of a pier column. The pier column will be between a pier cap and drilled shaft. The length of column is about 26 ft. My understanding is it will be a sway frame in y axis for sure but not 100% clear on x axis (y being the axis parallel to...
@ Bridgesmith, thank you for the response. To get clarification, Do yo mean to use the girder reaction due to pedestrian load as a UDL on the beam to determine the forces effect due to pedestrian load along the beam ?
Currently working on a load rating job. Using SAP to do a 2d model of the girder and then calculating capacities separately to determine the RFs. How do you load the exterior girder with sidewalk on it? AASHTO doesn't clearly specify anything about the loading to be used here. Attached is...
@hokie66 - I have come across a few bridges where this is a common phenomenon. Isn't the beam shortening accounted for in the bearing pad? Could the stiff joint filler material at the interface b/w cap and diaphragm cause this ? What kind of practice is used to repair and avoid this in future ?
@jayrod12 and bridgebuster, Thank you for responding, what is typically done to address the rotation ?Is it the bearing pad ? See below the image for interface b/w pier diaphragm and pier cap. I have also attached the bearing pad schedule. In my opinion, the bearing pads are too thin for the...
Hello,
I have come across a bridge that has diagonal cracks on the pier diaphragm as shown in the image. The bridge is a prestressed girder bridge. I know there are a number of reasons that could cause this but I have heard this is pretty common on prestressed girder bridges.
Can someone list...
Yes, the other end of the deck is free to slide. It's a single span bridge so one end has a fixed connection as shown above and the other end is free to slide. Thermal movement is restrained only in one direction
You should see the snip now. When you say move, do you mean move along the longitudinal axis of the bridge? In the case of the girder slab, we apply the horizontal temperature force on the abutment and then check for sliding, strength, service, and bearing. It should be a similar case here as...
Hello Guys,
I am working on the substructure design of a CIP Slab bridge.
Can anyone suggest how to determine TU/FR (Temperature and Friction forces) for the design of the substructure? I have attached the deck and abutment connection for your reference.
Typically in conventional girder...
Hello all,
Working on Pile foundation substructure. I have determined total lateral force in X and Z directions acting on the group of piles.
Was provided 1" deflection and 3" deflection lateral resistance by Geotech with a P multiplier of 0.8. Is it Geotech's responsibility to incorporate the...
Contractor made an error in placing the girder. Girder web is not concentric with bearing pad after girder erection. Center of girder web is at an offset of approx 1.5" from the center of bearing. What calcs does one show to justify this shouldn't be a problem ?
@JoelTXCive Why do you say the span is 6ft?, because of the traffic direction ?
To answer other questions yes, there is traffic on top of culvert. I don't have much cover to play with ( 6" to 1').
Thank you for the response,
What direction would my span be? The traffic is parallel to 44" and 42" dia pipes. The top slab is supported in all four direction. If I take my span to be 22.5 ft, It's going to require high reinforcement which isn't consistent with other similar drawings I have seen.
Hello everyone,
This is my first time posting here.
I need to design a junction box (see attached). Have received conflicting inputs from other sources on the design approach. Anybody here ever worked on something similar? I would like to get a brief design approach...