PMC2000-308
RELIABILITY ANALYSIS OF PRESTRESSED CONCRETE BRIDGE GIRDERS:
COMPARISON OF EUROCODE, SPANISH NORMA IAP AND AASHTO LRFD
A. S. Nowak, F. ASCE
University of Michigan, Ann Arbor, MI 48109-2125
Nowak@umich.edu
Chan-Hee Park
YonseiUniversity, Seoul, Korea chpark@yonsei.ac.kr J.R. Casas
University of Catalonia, Barcelona, Spain casas@etseccpb.upc.es Abstract
The objective of this paper is to compare the reliability level of prestressed concrete bridge girders designed using three codes: Spanish Norma IAP-98 (1998), ENV 1991-3 Eurocode 1 (1994), and
AASHTO LRFD (1998). Typical precast girders used in Spain are considered. Load and resistance parameters are treated as random variables. The statistical parameters are based on the available literature, test data and load surveys. Reliability indices are calculated by iterations. The results indicate that
Eurocode is more conservative than the other two codes, and AASHTO LRFD is the most permissive code.
Introduction
Recently, a considerable research effort has been devoted to bridge design and evaluation in Europe and in North America. However, the work has been carried out independently according to region-specific conditions. This study focuses on the comparison of the design codes for prestressed concrete bridge girders. The considered codes are: Spanish
Norma IAP-98, Eurocode ENV 1991-3, and AASHTO LRFD.
Five prestressed concrete bridges are selected. The structures were designed with typical
Spanish precast concrete girders. Spans vary from 20m to 40m and girder spacing varies from 1.3m to 3.4m. For comparison, three versions of the selected structures are considered, with the load carrying capacity determined by the amount of prestressing strands according to Norma IAP-98, ENV 1991-3 and AASHTO LRFD 1994.
The comparison criterion is structural reliability. Load and resistance are treated
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