Simplified Time-Dependent Column Shortening Analysis in Special Reinforced Concrete Moment Frames

  • Mohammad Jalilzadeh Afshari
    Affiliation

    Faculty of Civil Engineering, Semnan University, Semnan, Iran

  • Ali Kheyroddin
    Affiliation

    Faculty of Civil Engineering, Semnan University, Semnan, Iran

  • Majid Gholhaki
    Affiliation

    Faculty of Civil Engineering, Semnan University, Semnan, Iran

Abstract

Necessity for adaption of high-rise reinforced concrete structures’ design and practical steps of implementation through nonlinear staged analysis by consideration of long-term behavior of concrete have always been strongly recommended by researchers in recent years. Cumulative column shortening in conventional analyses is the most important consequence of neglecting the above issues. In this article, numerous modeling and extensive nonlinear staged analyses are carried out on structures with different geometrical characteristics and extremely simple empirical equations to estimate column shortening caused by creep, shrinkage and time changes of modulus of elasticity are provided in such a way that these relations can be independent of conventional parameters of ACI209R-92 regulations used in prediction of mentioned axial strains. Results obtained from validation of the proposed equations show high compliance of all proposed equations for up to 30 floors and also show accuracy of proposed shrinkage equation for the moment frame structures higher than the studied range.

Keywords: nonlinear sequential construction analysis, conventional one-step analysis, column shortening, creep, shrinkage, time development of modulus of elasticity
Published online
2017-09-25
How to Cite
Afshari, M. J., Kheyroddin, A., Gholhaki, M. “Simplified Time-Dependent Column Shortening Analysis in Special Reinforced Concrete Moment Frames”, Periodica Polytechnica Civil Engineering, 62(1), pp. 232-249, 2018. https://doi.org/10.3311/PPci.10679
Section
Research Article