APPLICATION OF AGITATION RAKE DREDGER

摘要

Lots of tidal barriers were built around China's coastal zone during past 50 years. Downstream tidal barriers suffer from severe siltation because of tide wave deformation and high sediment concentration near the seaward mouth. In order to reduce the sedimentation, tow-boat dragged rakes were adopted to agitate sediments downstream barrier and to let them flow down through upstream discharge. Such rakes have been studied and used in Jiangsu province since 1967. The rakes are improved step by step, i.e., single-side rake, twin-side rake, aerated-type rake and improved aerated rake, and the comparisons among various rakes are also made. Amount of 21.1 million m~3 siltation material was dredged with different rakes during past 26 years. Owing to the operation of agitation rakes the tidal barriers of the Sheyang River, Xinyang Estuary, Huangsha Estuary and Doulong Estuary can keep their capabilities to discharge upstream flood. Agitation rake has characteristics of high efficiency and low cost. The cost of using agitation rake for dredging 1 m~3 silt is only one fifth of that of using regular dredger.