Investigation on Performance of Green Belt as Coastal Protection against Waves

Document Type : Research Paper

Authors

1 Assist. Prof. Shahrkord Univ., Shahrkord, Iran

2 Prof. Shahid Chamran Univ., Ahwaz, Iran.

Abstract

In this study, in order to protect sea or river beaches against the force of the waves, the use of green belt (covering trees), rather than rigid systems such as breakwater, which are costly, have been proposed. The two dimensional experiment at the Wave channel was done, to assess the effect of tree cover on reducing the effects of waves. Plastic stem with a diameter of 1 cm was used on the Channel coast. Experiments were done with the tandem (parallel) arrangement at the intervals of 5 × 5 and 10 × 10 cm, 3 width modes covering 10, 30 and 40 cm, 5 beach slopes of 0, 3, 5, 7 and 10 percent, and 4 wave heights of 3, 4 , 6 and 8 cm. In general, with state of no cover, 145 cases were investigated. The incoming wave force on the beach was estimated with direct measurement method using an electronic dynamometer (load cell). Experimental results showed that coastal tree cover, to reduce the destructive waves have a great impact, by absorbing wave energy in the form of tensile force on the trees. In the best case of the tests, equivalent to 43% of the wave force was absorbed by tree cover.

Keywords


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