Time Dependent Performance Analysis of Flanged RC Beam in Limit State of Deflection

摘要

In this paper an attempt is made to formulate time dependent reliability analysis of flanged reinforced concrete beam in limit state of deflection. Normal range of flanged beams designed for limit state of safety as per the guidelines of IS 456:2000 for typical range of dead load and live loads are considered for evaluating time dependent failure probabilities. The algorithm takes into account the concrete maturation, tension stiffening, time dependent shrinkage and creep effect, variability related to material properties, dimensions and loads. Deterministic deflection model given in IS code is used to get deflection samples by Monte Carlo simulation technique. Further it is shown that time dependent probabilistic analysis of the structure can be done conveniently from the deterministic time dependent analysis with lognormal probability model at every time instant. There is a good agreement with Monte Carlo simulation technique. The present study demonstrates that structural response in terms of deflection over a given life time is directly related to design criteria used by structural engineer.