Evaluation of Wind Load Factors of RC Columns for Wind Load–Governed Limit State in Reliability-Based Design Code
Publication: Journal of Bridge Engineering
Volume 22, Issue 9
Abstract
This paper presents a general approach for evaluating wind load factors based on measured wind data for RC columns. Reliability analyses were carried out by an advanced first-order second-moment reliability method to investigate the wind load–governed limit state for the RC pylons of five cable-supported bridges in Korea. The axial force-bending moment (P-M) interaction diagrams of the pylons define the limit-state function. Load and strength parameters were considered random variables in the reliability analysis. The statistical parameters of wind load were determined by Monte Carlo simulation. Based on the results of the reliability analysis, dead load factors were set to the bias factors of dead load components, and a P–M interaction diagram drawn by the mean values of the strength parameters was used to define a design equation. The failure point of the wind load was obtained by equating the nonexceedance probability at the failure point of wind load to the probability of safety corresponding to a given reliability index. An analytical form of the wind load factor was derived in terms of the statistical parameters of wind load and the target reliability index. The wind load factor was adjusted to be used with the dead load factors and the resistance factor specified in a reliability-based design code. Validity of the proposed load factors was verified through a reliability assessment of the pylon sections of the five bridges. It is shown that the proposed load factors secure the target reliability levels within a 2% error.
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Acknowledgments
This research was supported by a grant (17SCIP-B119964-02-000000) from the Ministry of Land, Transport and Maritime Affairs of the Korean government through the Korea Bridge Design & Engineering Research Center of Seoul National University.
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Published In
Journal of Bridge Engineering
Volume 22 • Issue 9 • September 2017
Copyright
© 2017 American Society of Civil Engineers.
History
Received: Nov 9, 2016
Accepted: Apr 5, 2017
Published online: Jun 22, 2017
Published in print: Sep 1, 2017
Discussion open until: Nov 22, 2017
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