Robert Keith Dowell

US Patent:

20150088428, Mar 26, 2015

Filed:

Sep 23, 2013

Appl. No.:

14/034521

Inventors:

- San Diego CA, US
ROBERT DOWELL - San Diego CA, US

Assignee:

SAN DIEGO STATE UNIVERSITY RESEARCH FOUNDATION - San Diego CA

International Classification:

G01V 1/30

US Classification:

702 14

Abstract:

Seismic displacement demands for design of a bridge frame structure are typically determined from linear-elastic analysis (LEA), which are often incorrect, and compared to displacement capacity from a nonlinear pushover analysis. Nonlinear time-history analysis (NTHA) provides the most realistic assessment of displacement demands because it properly models the physics of the dynamic problem, wherein stiffness of the bridge varies over time. However, using NTHA to determine a bridge response from multiple earthquake motions based on the stiffness method requires excessive time. A unique approach for determining the nonlinear time-history response of a bridge frame is disclosed that is thousands of times faster than the stiffness method while providing the same results. Computational efficiency allows bridge design engineers to use NTHA for the seismic design of bridge structures by producing multiple determinations in less than one second. Displacement demands and capacities are based on nonlinear bridge behavior, resulting in safer bridge structures and reduced construction costs.