The accumulation of sediments on the bottom of sewer channels is responsible for significant hydraulic and environmental problems. For the removal of sediments the traditional and expensive mechanical devices have often been successfully replaced by hydraulic flushing gates, whose operation is based on the production of consecutive flushing waves able to bring into motion sediments deposited in sewer channels. This paper reports the results of an experimental investigation on the erosive performances of flushing waves on cohesive sediment beds. In particular, experiments were aimed to the evaluation of the effects of fine particles able to give cohesive properties to granular sediments. Experiments were performed in a laboratory flume using a simple flushing gate and adopting various hydraulic conditions for the generation of flushes. The effects of consecutive flushing waves were evaluated in terms of both deposit bed evolution and sediment masses flushed out of the flume. The experimental data derived from this investigation can be taken into account for the validation of numerical models specifically developed for the simulation of the effects of flushing waves on sewer deposits.
Flushing experiments with cohesive sediments
CREACO, Enrico Fortunato;
2006
Abstract
The accumulation of sediments on the bottom of sewer channels is responsible for significant hydraulic and environmental problems. For the removal of sediments the traditional and expensive mechanical devices have often been successfully replaced by hydraulic flushing gates, whose operation is based on the production of consecutive flushing waves able to bring into motion sediments deposited in sewer channels. This paper reports the results of an experimental investigation on the erosive performances of flushing waves on cohesive sediment beds. In particular, experiments were aimed to the evaluation of the effects of fine particles able to give cohesive properties to granular sediments. Experiments were performed in a laboratory flume using a simple flushing gate and adopting various hydraulic conditions for the generation of flushes. The effects of consecutive flushing waves were evaluated in terms of both deposit bed evolution and sediment masses flushed out of the flume. The experimental data derived from this investigation can be taken into account for the validation of numerical models specifically developed for the simulation of the effects of flushing waves on sewer deposits.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
