EVOLUTIONARY FEATURES OF BEIDAIHE NOURISHED BEACH

In this paper, taking the west beach of Beidaihe as an example, we analyzed the evolutionary features after beach nourishment through study of the changes in beach geomorphology and sediments distribution. One year after the beach nourishment project, the beach was obviously eroded. The average erosional volume per unit width was 44.8 m³/m and the average erosion distance of the beach berm was up to 15m. The erosion rate of eastern part of the beach was higher than that of the western part. Beach sediments were changed from coarse to fine in grain size and became well sorted. Four months after the nourishment project, the net transport tendency of the sediments was mainly alongshore in a direction from NE to SW. The beach off submerged breakwaters was eroded more severely without the protection of the offshore submerged breakwaters and there formed erosion hotspots as the result. One year after the beach nourishment project, 76% of the filling sands were retained and the beach geomorphology was similar to the expected. As a whole, the beach nourishment is rather successful.