A Method for the Combination of Stochastic Time Varying Load Effects

Pearce, H.T.; Wen, Y.K.

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https://hdl.handle.net/2142/14115 Copy

Description

Title

A Method for the Combination of Stochastic Time Varying Load Effects

Author(s)

• Pearce, H.T.
• Wen, Y.K.

Issue Date

1983-06

Keyword(s)

• Stochastic dependencies
• Load combination

Abstract

The problem of evaluating the probability that a structure becomes unsafe under a combination of loads, over a given time period, is addressed. The loads and load effects are modeled as either pulse (static problem) processes with random occurrence time, intensity and a specified shape or intermittent continuous (dynamic problem) processes which are zero mean Gaussian processes superimposed 'on a pulse process. The load coincidence method is extended to problems with both nonlinear limit states and dynamic responses, including the case of correlated dynamic responses. The technique of linearization of a nonlinear limit state commonly used in a time-invariant problem is investigated for timevarying combination problems, with emphasis on selecting the linearization point. Results are compared with other methods, namely the method based on upcrossing rate, simpler combination rules such as Square Root of Sum of Squares and Turkstra's rule. Correlated effects among dynamic loads are examined to see how results differ from correlated static loads and to demonstrate which types of load dependencies are most important, i.e., affect' the exceedance probabilities the most. Application of the load coincidence method to code development is briefly discussed.

Publisher

University of Illinois Engineering Experiment Station. College of Engineering. University of Illinois at Urbana-Champaign.

Series/Report Name or Number

Civil Engineering Studies SRS-507

Type of Resource

text

Language

en

Permalink

http://hdl.handle.net/2142/14115

Sponsor(s)/Grant Number(s)

National Science Foundation Grants CME 79-18053 and CEE 82-07590

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