1. AISC Seismic Provision 2002 Section 8.5 doesn't specify the use of amplified seismic loads for base connection design. However, at the end of the commentary C8.5, it says,
" In the case of Moment Frames, if the building system performance intends column yielding at the base plate, the connection between the column and the base plate should be designed for the Amplified Seismic Load."
My building is in Seismic Design Category D, the frames are intermediate steel moment frame, and the lateral columns are fixed based. Does that mean that I have to design the frame to let the column yield at the base plate?
2. If I used the Amplified Seismic Loads for base plate design, how about the anchor rod embedded in concrete footing? We are required to use ACI 7-02 Appendix D to check the anchorage. I don't think the concrete will work for the huge break out force resulting from the amplified seismic loads. We can put a lot reinforcing bars around the anchorage, but first of all, is it necessary to use the amplified seismic loads to check this anchorage?
Thanks a lot!
" In the case of Moment Frames, if the building system performance intends column yielding at the base plate, the connection between the column and the base plate should be designed for the Amplified Seismic Load."
My building is in Seismic Design Category D, the frames are intermediate steel moment frame, and the lateral columns are fixed based. Does that mean that I have to design the frame to let the column yield at the base plate?
2. If I used the Amplified Seismic Loads for base plate design, how about the anchor rod embedded in concrete footing? We are required to use ACI 7-02 Appendix D to check the anchorage. I don't think the concrete will work for the huge break out force resulting from the amplified seismic loads. We can put a lot reinforcing bars around the anchorage, but first of all, is it necessary to use the amplified seismic loads to check this anchorage?
Thanks a lot!