Concrete Arch

[PrecastDroopy]

In a concrete arch, pinned at both ends, what do you use to determine the maximum moment in the concrete arch member?

 

[bridgebuster]

A two hinged arched is statically indeterminite; you can use the force method, the displacement method, the column analogy. If you have Roark's Formulas for Stree & Strain there are solutions.

 

[PrecastDroopy]

Right, I figured it would be easier on my head to use a three hinged arch. So did the owner, and the E.O.R. Now in the design of this arch are there any suggestions on the details for the hings at the top of the arch or the base? A second question is what moment do you design the arch for? How do you determine the amount of steel or reinforcement required?

 

[3dboy]

You need to do a structural analysis of your set-up. you can either do it by hand or by computer analysis. once you know your moment diagram you can determine the tension face and size your rebar accordingly

 

[AlohaBob]

The algorithm for determining the forces, stresses and deflections of the arch are based on the basic basic equations of analysis. But you need a mathematic model of the arch, as it's original shape gets integrated into the equations which isn't quite so obvious for their constant use in linear members.

Maximum bending and deflections come from point loads and unbalanced uniform loads.