Strength and ductility of concrete columns externally reinforced with fiber composite straps

Hamid - Saadatmanesh, M. R. Ehsani, M. W. Li

Research output: Contribution to journalArticle

360 Citations (Scopus)

Abstract

Bridge failures in recent earthquakes such as the 1989 Loma Prieta earthquake have attracted the attention of the bridge engineering community to the large number of bridges with substandard seismic design details. Many concrete columns in bridges designed before the new seismic design provisions were adopted have low flexural ductility, low shear strength, and inadequate lap length for starter bars. These problems, compounded by flaws in the design of structural systems, have contributed to the catastrophic bridge failures in recent earthquakes. In this paper, a new technique for seismic strengthening of concrete columns is presented. The technique requires wrapping thin, flexible high-strength fiber composite straps around the column to improve the confinement and, thereby, its ductility and strength. Analytical models are presented that quantify the gain in strength and ductility of concrete columns externally confined by means of high-strength fiber composite straps. A parametric study is conducted to examine the effects of various design parameters such as concrete compressive strength, thickness and spacing of straps, and type of strap. The results indicate that the strength and ductility of concrete columns can be significantly increased by wrapping high-strength fiber composite straps around the columns.

Original languageEnglish (US)
Pages (from-to)434-447
Number of pages14
JournalACI Structural Journal
Volume91
Issue number4
StatePublished - Jul 1994
Externally publishedYes

Fingerprint

Ductility
Concretes
Fibers
Composite materials
Earthquakes
Seismic design
Starters
Strengthening (metal)
Shear strength
Compressive strength
Analytical models
Defects

ASJC Scopus subject areas

  • Civil and Structural Engineering

Cite this

Strength and ductility of concrete columns externally reinforced with fiber composite straps. / Saadatmanesh, Hamid -; Ehsani, M. R.; Li, M. W.

In: ACI Structural Journal, Vol. 91, No. 4, 07.1994, p. 434-447.

Research output: Contribution to journalArticle

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