Abstract
The building of jetties or other types of projecting walls along straight coasts has had disasterous effects on many beaches. Therefore, the problems of stabilization and restoration of the beaches are the most widespread problems on shore-control. In the coastal zone design of engineering works has been considered about the materials to be employed and the forces they must withstand. But, the modifications by the works that will introduce in the natural sedimentation processes operating in the coast and nearshore zone will be needed. The Kashima Nada beach can be divided into different types on the basis of beach topography, grain size, sand fraction composition and Froud number; scour holes beach, ridge-unnel beach, and cusp beach. The scour hole type beach is eroded inconsiderably. The ridge-unnel type is the stable beach in a change of a season. The cusp type beach is classified into the looser beaches and the steeper beaches of foreshore slope. The first beaches are being calm area, and stable or sedimentarily tendency beaches. The second beaches have a characteristic of scour holes type, and they are the stable beaches or erosional beaches. The erosional beaches are changed into a static stable beach by the making a large arcuate rate. However, it is desirable for beach enterprise to consider it with a large viewpoint because the erosional beaches are source of supply of drift sand. Enough knowledge of coastal and nearshore processes with varying accuracy and precision is obtained through processes operating in the Kashima Nada beach. It is possible to provide qualitative predictions of the effect of engineering works in the natural sedimentation processes and subsequent consequences.
