Numerical Simulation Of Stress Distribution Of Armor Blocks On The Slopes Under Wave Action

The rubble mound breakwater is the protective structure widely used in port and coastal engineering. The armor block layer should have the wave dissipation effects, but also to maintain their stability. But under extreme wave condition, these amour block layer may be prone to hydraulic instability and structural instability which caused by the block fracture failure. Till now, the major method to study stability of breakwater is physical model experiment. Unfortunately, due to the scale-effect, experiment results often cannot correctly reflect the prototype structure strength. Therefore, it has very important academic significance and engineering application value to carry out the prototype scale numerical simulation of the strength failure of the mound breakwater armor blocks under wave actionThe paper based on FEM/DEM method presents a2D prototype scale numerical model to simulate internal stress distribution, cracks formation and fracture process of armor blocks on the slopes under wave action. The hydrodynamic loads on the structures are simulated by the small amplitude wave theory.The armor blocks movement and deformation are simulated using the FEM/DEM method. The distributed contact force is calculated by the penalty function method based on potential function. The combined single and smeared crack model is used to simulate the crack of concrete block. Numerical solution is calculated by the central difference explicit integration algorithm. It simulates block gravity stress distribution and the two types of block collision damage and verifies the stress and deformation calculation accuracy of numerical model. Numerical simulation gives the armor blocks movement characteristics, the internal stress distribution, crack formation and fracture process on the slopes under different wave loads. It gives stress duration curves of different points, analyses the block internal stress variation discipline under different wave loads. The block movement tendency and the fracture failure properties are analyzed under extreme wave condition.Based on3D FEMDEM method, it presents a three-dimensional prototype scale numerical model to simulate internal stress distribution of armor blocks on the slopes under wave action. The finite element is high precision finite strain finite rotation quadratic tetrahedron element. The internal stress distribution of the concrete accropode blocks under gravity are compared and analyzed with ANSYS model. It simulates dynamic stress change of the block dropping collision and verifies the accuracy of stress calculation of the3D numerical model. By the application of the numerical model, the distribution and change features of amour blocks internal stress on the slopes in rule put under the linear wave are simulated. It gives stress duration curves of different points and gives the stress distribution and block movement trends at different times. The stress change properties within the blocks are deep analyzed.The numerical simulation turns out that blocks collide with each other under the action of wave, and maximum stress occur on the contact point, sometimes on connecting part of blocks. Surface stress changes periodically with the waves. Concrete accropode blocks have good stability on the whole, less prone to local or global instability. The movement trend of single block is given priority to with translation and tumbling. In the extreme sea conditions, fracture failure of individual concrete blocks may occur in two limb joints. It should be strengthened in engineering. The research work will provide reference for the design of breakwater armor block.