Long-term behavior of prestressed old-new concrete composite beams

Wen Wei Wang, Jianguo Dai, Guo Li, Cheng Kui Huang

Research output: Journal article publicationJournal articleAcademic researchpeer-review

21 Citations (Scopus)

Abstract

This paper presents both theoretical and experimental studies of the long-term behavior of prestressed old-new concrete composite beams under sustained loads. General differential equations governing the relationship between the incremental deflection and incremental internal forces of the composite beams were deduced in the theoretical study. Closed-form solutions for simply supported composite beams were obtained and validated using test results reported in previous literature on steel-concrete composite beams. The experimental investigation consisted of static long-term load tests carried out on four prestressed old-new concrete composite beams. The behavior of the old-to-new concrete interface, time-dependent deflections, concrete strains, and prestress losses was carefully observed over 260days. The long-term test program showed that the midspan deflections and concrete strains increased with time because of creep and shrinkage of the new prestressed concrete. The slip strains at the old-to-new concrete interface were found to be relatively small, indicating that the interface bond was sound enough to prevent slip and that the prestressing loads were effectively transferred to the old concrete. The proposed theoretical models predicted the long-term behavior of the prestressed old-new concrete composite beams with an acceptable degree of accuracy.
Original languageEnglish
Pages (from-to)275-285
Number of pages11
JournalJournal of Bridge Engineering
Volume16
Issue number2
DOIs
Publication statusPublished - 1 Mar 2011

Keywords

  • Creep
  • Incremental model
  • Long-term deflection
  • Old-new concrete composite beam
  • Old-to-new concrete interface
  • Prestress
  • Prestress loss
  • Shrinkage

ASJC Scopus subject areas

  • Civil and Structural Engineering
  • Building and Construction

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