Is it reasonable to Interpolate wind loads on 45 degree corner?

[tristrium]

Hi all

I am designing a noise wall that that has multiple 45 degree (or 135 deg) changes in direction along its length.

Australian standard AS1170.2 Appendix D, stipulates that the pressure coefficient for a 90 degree corner formed in a wall is 1.8 vs 1.2 typically.

The commentary gives no guidance for any other angles.

Would like to get peoples opinion of if it is reasonable to interpolate between 1.8 (for 90 deg) and 1.2 (for 0 deg) giving a coefficient of 1.5?

We have space constraints for footings, hence why I would like to reduce if possible

[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1655859954/tips/Noise_wall_sa9sso.pdf[/url].

Thanks

 

[Tomfh]

What version of AS1170.2 are you using, and what tables are you referring to?

 

[tristrium]

Hi Tomfh

Thanks for the response.

I am using AS1170.2 (2011) Table D2 (C). See link below. AS1170.2 (2021) says the same, but it is not gazetted yet.

[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1655864163/tips/AS1170.2_extract_wp0ium.pdf[/url]

I know that ASCE 7-16 suggests that local pressure factors do not apply when wall angles are 135 deg (same as 45 deg from other side) but this is for a building. See link above.

 

[Tomfh]

Ok I understand your question now.

In my opinion 1.5 is reasonable. A 45 degree corner isn't going to catch the wind too badly. Also, isn't your corner post/footing braced by the return walls here?


The worst case is the free ends of the wall where Cpn = 2.4 or 3.0.

 

[tristrium]

Yes the corner posts are braced.

The affected zone is 2 times wall height however.

This wall is 14m high so it would extend 28m either side.

Thanks again