Lectures 2 and 3

Seismic Analysis, Behavior, and Design of Fixed-base RC Buildings

at Near-fault Sites

4.75 hours prerecorded, 1.5 hours discussion

Summary

This two-lectures-series develops a comprehensive understanding of the seismic behavior, analysis, and design of fixed-base reinforced concrete (RC) wall and RC frame buildings at near-fault sites. Lecture 02 starts with presenting the nonlinear response of SDOF oscillators approximating the fundamental mode of response of buildings. The nonlinear SDOF analysis is used to estimate displacement demands of buildings. The second half of Lecture 02 discusses the fundamentals of the nonlinear mechanics of RC walls and the displacement-based analysis of them including the relation between displacements, plastic rotations and material strains. 

Lecture 03 (3-hours prerecorded part) consists of five parts. The first part compares the ASCE 7-10 code minimum analysis versus 3D nonlinear response history analysis (3DNLRHA) of five RC buildings. The 3DNLRHA is conducted both at the Design Earthquake and the Risk-targeted Maximum Considered Earthquake seismic hazard levels. The buildings range from 5- to 20-story tall including both RC wall and RC special moment frame buildings. The reasons that ASCE 7-10 code minimum analysis underestimates significantly displacement, force, and floor acceleration demands are presented. The second part presents the key results from the landmark 7-story full-scale shake table test and the main experimental observations validate key results of the nonlinear analysis of the buildings case studies. The third part presents the enhanced response spectrum analysis, implemented in ETABS, method which improves significantly the calculation of design forces compared with conventional response spectrum analysis. Part IV discusses how the seismic performance of fixed-base RC buildings can be enhanced by increasing the strength and the effective stiffness of the building. The last part covers the modeling and nonlinear response history analysis of RC buildings in ETABS Ultimate.

  • Nonlinear mechanical behavior of RC walls

  • Nonlinear response of SDOF oscillators at near-fault sites

  • Seismic response of RC wall and frame buildings (5- to 20-story tall) designed per ASCE 7-10

  • 3D nonlinear response history analysis (3D-NLRHA)of fixed-base RC wall and frame buildings

  • Comparison of 3D nonlinear dynamic analysis and ASCE 7 minimum analysis requirements

  • Enhanced response spectrum analysis calibrated with 3D-NLRHA

  • Improved seismic performance via increase of stiffness and strength