[RC] Moment bearing capacity of rectangular RC section with double reinforcement (Eurocode 2)

In this post I'll write about moment bearing capacity of rectangular RC section with double reinforcement. 

Sometimes in my working practice I need to calculate bearing capacity of existing beams. But the most common aims for RC Eurocode analysis doesn't consist any information for this case. And I try to answer on this question:)

Just see bottom pictures:) Download pdf link 1 и link2