SIMULATION METHODS FOR ARTIFICIAL NEARSHORE SANBARS FOR COSTAL PROTECTION AND BEACH NOURISHMENT

Facing the severe coastal erosion in coastal beaches and the increasing awareness of environmental protection of the public, new engineering measures aiming at coastal protection and beach nourishment have rapidly been developed recently. Artificial sandbar is one of the choices highly favored by coast engineers in coastal protection. In the coastal protection and beach nourishment project of Beidaihe, artificial sandbar has been successfully applied. Both physical simulation and numerical simulation were carried out by the authors to study the interaction of environmental dynamics and sediment transport in both the waters and sandbars. Physical simulation experiments were made under similar conditions, production process and control conditions and numerical simulation was carried out with Delft3D on sandbar deformation and coastal evolution in response to extreme wave conditions. Comparative studies were conducted for the results from the two methods. Results show that the physical simulation experiment is intuitive, rapid and highly accurate; and numerical modeling requires constant adjustment of computation parameters, verification of the convergence in sediment calculating process and examination of reasonableness of computational results. A number of validation studies on numerical model are required in order to obtain the equal precision of the physical simulation.