No. 31. Think Globally, Build Locally Third fib Congress Proceedings - 29 May - 2 June 2010 - Washington D.C., USA PDF format

If concrete bridge systems are constructed on very soft soil that may experience liquefaction during a severe earthquake, it is difficult to prevent yielding of the pile foundation. In this study, a prestressed reinforced concrete pile using high-strength materials is developed to increase flexural capacity.

The main structural characteristics of the developed pile are as follows: (1) the neutral axis remains close to the centroidal axis of the pile, even when longitudinal reinforcement yields under flexural moments, because the pile is subjected to a high axial compressive force induced by prestressing steel tendons. This means that the concrete in the compression zone can contribute to increasing the flexural strength of the pile; and (2) the use of carbon fiber sheets to prevent spalling of the cover concrete contributes to increasing the flexural strength of the pile.

The results of bending tests show that the proposed prestressed reinforced concrete pile with carbon fiber sheets and infilled concrete has a higher flexural capacity than a pile without these enhancements, and it does not exhibit brittle failure behavior.