随着海岸侵蚀的日益加剧和人类对环境保护意识的增强,新型护岸养滩工程措施不断涌现,其中近自然的海底人工沙坝更是受到海岸工程界的青睐,并已在北戴河海滩恢复治理工程中得到成功应用。基于北戴河海域环境动力、泥沙输运和人工沙坝间的相互作用,从物理模拟和数值模拟两个方面进行研究。首先阐明物理模型试验所遵循的相似条件、制作方法和控制条件,并利用Delft3D软件对极限波高作用下的沙坝变形与岸滩演变进行了数值模拟,再将两种方法得到的地形结果进行了分析比较。研究结果表明:物理模型试验具有直观、快捷和精度较高的特点;数学模型则需不断调整计算参数、检查泥沙计算过程中的收敛性和成果的合理性。经反复验证的数学模型,其计算结果可以达到物理模型试验所要求的工程精度。
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 cal- culating 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.