NEHRP Clearinghouse

Title
Aseismic Design Procedures for Reinforced Concrete Frames. Seismic Behavior and Design of Buildings, Report No. 1.
File
PB80104128.pdf
Author(s)
Biggs, J. M.; Lau, W. K.; Persinko, D.
Source
National Science Foundation, Washington, DC. Engineering and Applied Science., July 1979, 90 p.
Identifying Number(s)
R79-21
Abstract
Twelve reinforced concrete frames are designed for earthquake and gravity loads using three different procedures for determining the seismic design loads. The procedures are: (1) UBC static load approach; (2) modal analysis using inelastic response spectra; and (3) Substitute Structure Method. The frames are of 4, 8 and 10 stories. The validity of each design procedure is evaluated by time-history analysis of each frame to determine maximum local ductility demands due to both real and artificial ground motion. None of the three methods is found to be completely satisfactory because the ductility demands are not the same as intended in the design and are not evenly distributed over the frame. However, the computed ductility demands are in no case large enough to indicate structural collapse and in this sense all three methods produce satisfactory designs. Although the inelastic response spectrum approach produces slightly better results, the two more sophisticated methods do not produce significantly better designs than the simpler UBC approach.
Keywords
Seismic design; Earthquake resistant structures; Framed structures; Reinforced concrete; Seismic waves; Earth movements; Dynamic response; Buildings; Earthquake engineering; Ground-motion; Earthquakes; Dynamic structural analysis