This study is undertaken to find out the most reliable breaker height formulas that predict well for a wide range of hydraulic conditions. The applicability of 24 existing formulas, for computing breaking wave heights, is examined by using wide range and large amount of published laboratory data (574 cases collected from 24 sources). It is found that most formulas predict well for the breaking waves on the gentle slope (0 < m ≤ 0.07), but the prediction is unsatisfactory for the breaking waves on the steep slope (0.1 < m ≤ 0.44). Three formulas are selected and are modified by including the new form of bottom slope effect into the formulas. The new breaker height formulas predict well for wide range of wave and bottom slope conditions. Keywords: Breaking wave, breaker index, incipient wave breaking. 389 Coast. Eng. J. 2000.42:389-406. Downloaded from www.worldscientific.com by UNIVERSITY OF CALIFORNIA @ SAN DIEGO on 06/04/15. For personal use only.

This paper presents the results of an experimental study on the compressive behaviour of concrete confined by natural fibre-reinforced polymer (NFRP) jackets which are formed by embedding sisal fibres in an epoxy resin matrix. The sisal fibres are one of the cost-effective materials for use in seismic strengthening applications where a moderate increase in strength and ductility is required. This study has two main objectives: the first is to investigate the effectiveness of NFRP composites in increasing the strength and deformability of confined concrete. For the second objective, the performance of existing strength models developed for conventional synthetic fibre-reinforced polymers is assessed. For this, 36 concrete specimens were tested under uni-axial compression. The study parameters covered the NFRP thickness, concrete strength and cross-sectional shape. Test results indicated that the NFRP confinement is significantly effective in increasing the strength and deformability of confined concrete. Furthermore, it is found that none of the existing considered models is capable of accurately predicting the ultimate strength and strain of NFRP-confined concrete. Finally, new strength models are proposed to predict the compressive strength of circular and square sections. The strengths predicted by the proposed models are found to have a good agreement with experimental results.

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Many experimental and theoretical investigations have been carried out to study the compressive strength of concrete confined externally with unidirectional fiberreinforced polymer (FRP) composites. These unidirectional FRP(s) include carbon, glass, aramid, polyethylene terephthalate, and polyethylene naphthalates. In this article, the performance of randomly distributed sprayed fiber-reinforced polymer (SFRP) composites on the enhancement of strength and deformability of concrete column through external confinement is investigated. The salient features of SFRP are quick and easy application as well as the uniform tensile properties in all directions. In the present study, 24 small concrete specimens were loaded to failure under the uniaxial compression loading. The study parameters covered SFRP thickness, fiber length, and column sectional shape (circular and square). Test results showed that the external confinement by SFRP is significantly effective to increase the strength and deformability of confined concrete. Based on the experimental results, the performance of existing strength models developed for the unidirectional FRP is assessed to examine its applicability to the SFRP confinement. It is found that none of the existing models is capable of accurately predicting the strength of concrete confined with SFRP. Finally, new strength models based on a linear relationship between confined concrete compressive strength and lateral confining pressure are proposed to predict the compressive strength of circular and square sections. The strengths predicted by the proposed models are found to have a good agreement with experimental results. POLYM. COMPOS., 00:000-000, 2015.