## Abstract

The long-term variation of bending moment distribution caused by creep in a continuous beam erected sequentially in span-length sections with overhangs is analyzed. A linear aging creep law is assumed. The problem involves changes of the structural system from statically determinate to indeterminate, a gradual increase in the number of redundant moments, and age differences between various cross sections. A system of Volterra integral equations for the history of support bending moments is derived. By considering infinitely many equal spans, which is good enough whenever there are more than a few spans, one can take advantage of a periodicity condition for the construction cycle; this reduces the problem to a single equation which is of a novel type in creep theory—an integral-difference equation involving time lags in the integrated unknown. The solution exhibits sudden jumps at times equal to multiples of the construction cycle. The jumps decay with time roughly in a geometric progression. Approximation of time integrals with finite sums yields a large system of simultaneous linear algebraic equations. These equations cannot be solved recurrently, step-by-step. By solving the large equation system with a computer, the effects of the duration of the construction cycle, of concrete age at assembly of span from segments, and of the overhang length are studied numerically.

Original language | English (US) |
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Pages (from-to) | 1648-1668 |

Number of pages | 21 |

Journal | Journal of Structural Engineering (United States) |

Volume | 109 |

Issue number | 7 |

DOIs | |

State | Published - Jul 1983 |

## ASJC Scopus subject areas

- Civil and Structural Engineering
- Building and Construction
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering