How to restrict bending of beam in local z-direction?

Creation date: 6/4/2021 3:26 PM Updated: 4/21/2023 12:51 PM midas civil section stiffness scale factor

Question:

Hi there,

I have a 3D beam model which represents a bridge pier, I am trying to alter the section properties of the beams so that the horizontal beams don't bend in the local z direction which would create deep beam behaviour. How to I do this? I tried using section stiffness manager but cant seem to get it to work. Can you assist?

The image above details what I am looking to achieve.

Answer:

Hello,

Assuming that "horizontal beams don't bend in the local z direction" refers to deformation in local z-direction within the beam should be reduced. Kindly verify this.

If the deformation in local z-direction are to be reduced, the high stiffness scale factor in Iyy is given as shown below for the horizontal curved beam elements.

Further, while reviewing the model, the node 76 and 110 are very close. Thus connection between element 125 and 124 is not proper as shown below.

This can be improved by using merging node option under node/element tab as shown below.

After improving the model, the deformations in Dz for test case in horizontal curved beam is shown below. Each Horizontal curved beam deform vertically as whole and don't bend like normal beam does.

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	Centre Pier.mcb 134 KB

How to restrict bending of beam in local z-direction?

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