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The bridge model is not getting analyzed properly. What steps can be taken to resolve this issue?

Question:

This bridge is entirely a reinforced concrete bridge, and I need to perform a load rating for it, but I cannot even get the structural analysis results. I have modeled this bridge according to its plans. I have all the required boundaries set, deck in place, loading patterns, etc., and I get warning messages and no structural analysis results.

I have attached all applicable files in regards to this particular bridge.

Answer:

Since the main issue was about rating, first of all, kindly note that in midas Civil, rating is possible only for PSC & Steel Composite bridges.

So, if it is intended to rate a RC bridge, tendons with negligible properties could be assigned and then PSC rating could be done for this. However, kindly note that this is a workaround.

As for this particular model, actually the modelling isn't correct. The supports are provided at only one end and the moment is released. Thus it is unstable. I just assigned support at other end and now it is being anlyzed.

Also, the material properties are not correct. 2500ksi is way too much compressive force for concrete. Even steel is around 60ksi. I believe that could be due to mistake with units. It should be 2.5ksi.

The modified model file is attached for review.

Creation date: 10/17/2018 9:57 PM Updated: 6/30/2023 3:34 PM

Center Drive Bridge.mcb

Center Drive Bridge.wzd

Curb Girder.dxf

Curb Girder.sec

Island Flanking Girder.dxf

Island Flanking Girder.sec

Main Girder.dxf

Main Girder.sec

Sidewalk Flanking Girder.dxf

Sidewalk Flanking Girder.sec

Files		Sort by Name Sort by Date
	Center Drive Bridge.mcb 248 KB
	Center Drive Bridge.mcb 274 KB
	Center Drive Bridge.wzd 82 KB
	Curb Girder.dxf 95 KB
	Curb Girder.sec 919 b
	Island Flanking Girder.dxf 95 KB
	Island Flanking Girder.sec 973 b
	Main Girder.dxf 95 KB
	Main Girder.sec 914 b
	Sidewalk Flanking Girder.dxf 95 KB
	Sidewalk Flanking Girder.sec 932 b