Do everyone design all the sections that come to their office by calculation or do design by previous experience?

it depend designers could use drawings from previous lesson learned, but it all depend on scenario and current situation and requirements 

Ofcourse.

We Engineer's still believe in hand calculations rather than depending on the design softwares available in market today.

For complex Structures definitely one has to be thorough in the design software & has to be dependent on the output results. Well cross checking of sections design with hand calculation is preferable.

That depends on the type of structure. If the section is more likely to the previous ones, then the design will almost the same inspite only few variations will be there. But each section designs varies accordingly.

I agree with Gentlemen answers 

thanks for invitation 

I am working in the office & I am design by calculation becouse in this way you keep your information all the time fresh and you can provid this calculation whenever needed 

you can yous your previous exp. to combear or put so numbers to get the best resilt of calculation from the first time 

Franckly, sometimes , designers uses their experince but not when designs are critical..

I agree with Eng. Talal.... thank you