Modeling of the solid transport of Medjerda on the section Sidi Salem - El Herri

The object of this study is to quantify the solid flow transportation of the Medjerda river alongside the section Sidi Salem - El Herri in order to find adequate solutions for its sedimentation. Three methods were used to determinate the solid flow : the nuclear technique, the turbidity and the method of filtration. These methods allow measuring the suspended elements transported by the water. For that, we need to use numerical models to consider the entirety of the solid transport. These are the models of Bagnold and of Einstein. The model of Bagnold allowed estimating a value of solid concentration that varies between 0.97 and 6.19g/1 in different depths of the Medjerda river, during the average floods. The model of Einstein estimate solid concentrations which are including between 0.2g/1 and 4g/1, for low -water level period. These values are rediscovered by direct maesures by taking samples from the same sections, for the same analysis period of the solid transport. These results drove us to the validation of the models of Nagnold and Einstein for the Madjerda river. The quantification of solid transport by direct maesures (nuclear technique, filtration, turbidity ), or by modelling, allowed us to explain the importance of the solid deposits on the bed of the river and to relate the consequence of this phenomenon on the morphology of Medjerda river particularly on the section Sidi Salem-El Herri. (author). 12 refs