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Civil Engineering/orthogonal earth. effect?


dear Mr. esmailzadeh
thank you for past guidance
in the all seismic cods,there is this remark:if members was intersection of two seismic lateral system . these members should designed for 100 percent of the forces for on direction plus 30 percent of the forces for perpendicular direction.
so my question : the columns of concrete frame is include this remark?if yes,why?
thanks a lot

Dear Behzad

Unfortunately I couldn't reply to your e-mail due to Internet and e-mail restrictions. Sorry for the inconvenience.

The 100-30-30 is not a ductility oriented regulation but a loading pattern related concept modelling approximately the effect of seismic loading occurring in the worst possible direction. In fact all columns which are members of 2 orthogonal systems will be affected by this pattern of loading.


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Babak Esmailzadeh Hakimi


I can answer questions in Structural Engineering, Earthquake Engineering, Project Management and Project Control topics!


I am experienced in the area of earthquake engineering in electrical power industry, i.e. Lifeline Earthquake Engineering. My focus has been on structural seismic design of power installations. Recently I have got involved in project management in the category of constructional engineering.

Sinam Consulting Engineers Co.

Bs degree in Civil Engineering from Ferdowsi University ,1988, Mashhad Iran, Ms degree in Earthquake Engineering, Sharif University of Technology, 1993, Tehran, Iran

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