bridge analysis

[kangudi]

Hi

I am busy with the design of concrete bridge. the length is 24m and the bridge is divided in four(4) equal span of 6m. At the internal support I have expansion joints. My question is how to analyse the bridge. My approach was to analyse it as a single span of 6m because the expansion on the support will give me zero moment and because of the expansion joint at the internal support I did not think to analysis it as a continuous beam ( 4 span of 6m each) because that will give me a sagging and hogging moment. Can someone help on that.

 

[JedClampett]

You're correct. But this is one of the most basic concepts in structural and bridge design. If you're designing a 24 meter long bridge and need this clarified, it scares me.
Is this a student project?

 

[jsha811]

JedClampett is right. This is very basic.
There is a free program developed by WSDOT and TX Dot called PGSuper.
That is used for design bridges.Not sure what kind of superstructure you have though.


Moment curvature analysis,reinforced concrete column design and prestressed concrete pile design at

http://www.structurexpress.com

 

[Mixtli]

That assumption is correct, but there is a whole lot of things to do to get a complete bridge design.
I suggest you get a consultant to guide you, it is too much to run it by this forums.

Good Luck

M.

 

[iain98765]

Mixtli,

Help the guy out if you can that's what this forum is for. Advising him to go to a consultant because it is complicated maybe one answer, but if that were the answer for all the posts in this forum, it would cease to exist!

 

[iain98765]

E.g list the whole bunch of things he needs to do!

 

[bridgebuster]

iain98765 - the members of ET are usually quite helpful but sometimes a question isn't deserving of a detailed answer.

JedClampett summed it up well: "If you're designing a 24 meter long bridge and need this clarified, it scares me. "

 

[TomDOT]

Bleah. I really dislike multitudes of expansion joints on bridges - even sealed ones. They always fail and let debris/water/salt accumulate on the substructure and/or fill with debris in the joint itself so that they no longer actually allow expansion.

Complicated drainage systems are almost as bad. I once spotted a drain pipe with 11 (Yes, ELEVEN!) 90-degree elbows. No wonder it was full of debris and didn't actually drain any water.