Date of Award
Doctor of Philosophy (PhD)
Keith A. Porter
M. Amin Hariri-Ardebili
This thesis tests three hypotheses: (1) Some US practice to determine the required separation distance to preclude pounding between neighboring buildings is overly conservative. (2) Pounding between buildings with aligned floors significantly contributes to collapse. (3) Above-code design of a common engineered commercial building type is cost effective in many though perhaps not all US locations, at least from a benefit-cost-analysis perspective.
The first part of this thesis reexamines the required minimum permissible space between two adjacent buildings to preclude earthquake pounding. This part of the thesis employs and compares three analytical approaches to estimate the minimum safe distance conditioned on the occurrence of risk-targeted maximum considered earthquake (MCER) shaking. 1) First, safe separation distance between buildings is estimated using elastic spectral displacement response of adjacent buildings at the top of the shorter building, accounting for mode shape and the height difference. 2) ASCE 7-16’s equivalent lateral force procedure is also examined. 3) Finally, multiple linear elastic dynamic structural analyses of two adjacent buildings are performed, factoring drift estimates by ASCE 7-16’s Cd/R to approximate nonlinear response. To examine diverse, though not exhaustive, conditions, this thesis examines 3 combinations of shearwall and steel moment frame buildings; 5 building heights between 2 and 26 stories; fundamental periods of vibration vary between 0.2 sec and 2.8 sec; and 4 locations with degrees of seismicity in roughly equal increments corresponding to short-period mapped spectral acceleration response SMS from 0.8 to 3.0g.
Part 2 repeats much of the analysis of part 1, but with an additional structural analysis procedure (nonlinear dynamic analysis) but with a narrower set of building types. As with part 1, this part evaluates the required minimum permissible space between two adjacent buildings to preclude earthquake pounding. Unlike part 1, this part develops a set of conversion factors to relate the separation distances calculated by any of the simpler methods (elastic spectral displacement, equivalent lateral force, and multiple linear elastic dynamic structural analyses) to multiple nonlinear dynamic structural analyses method. This part examines 3 combinations of special reinforced concrete moment frame buildings, SMF, and ordinary reinforced concrete moment frame buildings,
Isteita, Moad, "Studies of Earthquake Pounding Risk and of Above-Code Seismic Design" (2019). Civil Engineering Graduate Theses & Dissertations. 484.