Title:
SP-339-08: Trends in Demands for Concrete Performance-Based Seismic Design Towers
Author(s):
Kevin Aswegan and Ian McFarlane
Publication:
Symposium Paper
Volume:
339
Issue:
Appears on pages(s):
121-133
Keywords:
concrete shear walls, PBSD, performance-based seismic design
DOI:
10.14359/51724699
Date:
3/1/2020
Abstract:
The use of a Performance-Based Seismic Design (PBSD) approach to design buildings whose heights exceed 240 ft (73 m) has become common in many West Coast cities. This paper studies trends across 14 special reinforced concrete shear wall PBSD towers designed within the last 5 years. The primary purpose of evaluating these trends is to compare demands calculated using a linear elastic design approach (i.e. for Design Earthquake or Service Level shaking) to the demands (average results from 7 or 11 ground motions) determined through nonlinear analysis (i.e. for Maximum Considered Earthquake shaking). The specific demands evaluated include core wall shears and foundation overturning moments. The paper also demonstrates that shear and moment amplification are significant phenomena for concrete buildings, and are believed to be primarily due to nonlinear behavior, material over-strength, higher mode effects, and damping and stiffness assumptions. The results present a useful range of trends to provide an engineer guidance on the expected demands and the level of variability between projects. The paper highlights some of the reasons for the variability in these trends, and provides general proportioning recommendations.
Related References:
ASCE (American Society of Civil Engineers). (2010). Minimum Design Loads for Buildings and Other Structures, Reston, VA.
LATBSDC (Los Angeles Tall Buildings Structural Design Council). (2015). An Alternative Procedure for Seismic Analysis and Design of Tall Buildings Located in the Los Angeles Region, 2014 Edition with 2015 Supplements, Los Angeles, CA.
PEER (Pacific Earthquake Engineering Research Center). (2010). Guidelines for Performance-Based Seismic Design of Tall Buildings, TBI Guidelines Working Group, Berkeley, CA.
PEER (Pacific Earthquake Engineering Research Center). (2017). Guidelines for Performance-Based Seismic Design of Tall Buildings Version 2.01, Tall Buildings Initiative, Berkeley, CA. ACI (American Concrete Institute). (2014). Building Code Requirements for Structural Concrete (ACI 318-14), Farmington Hills, MI.