Development of dredging method for hard-packed sand

In the case of dredging of hard-packed sand, reduction of solid concentration and wear of cutter teeth of the dredge head, etc. can pose some problems, and moreover impact on the environment must be taken care of sufficiently. Model tests were performed to solve these problems using some improvements of a cutter suction dredger. It has become obvious that if a light soil-water mixture recycling system is used in combination with the improved type cutter head with anti-pollution cover, the loaded soil volume in the hopper is improved greatly, and that it is also possible to prevent pollution at the same time.