please any one can guide me on this issue
Qno1 : As in the multistory building the bottom story columns has high strength concrete(5ksi) while the top stories columns has low strength concrete ( 3Ksi) , Is there any conflict with code ,practice and does it effect the performance of building during earth quack load or gravity load ?
QNO2 : if the column has high strength concrete than beam does it effect the performance of building during earth quack load or gravity load and transfer of loads between beam & column?
Qno3: if the Concrete strength of foundation is less than Column concrete strength ? will it be ok according to load transfer or codes ?