When you are piling things on top of each other, by nature you will have a pyramid shape. Your mass will be bigger at the bottom, smaller than what you have up higher. When you have wave action, if it is going close to the top, it will start working its way through the structure, which can erode it and create a failure.

When you are piling things on top of each other, by nature you will have a pyramid shape. Your mass will be bigger at the bottom, smaller than what you have up higher. When you have wave action, if it is going close to the top, it will start working its way through the structure, which can erode it and create a failure.

Guillermo Ramirez

It was fast - it happened in a matter of hours. But it probably was a gradual degradation of your structural system. You started increasing the pressure. For a concrete all, it could be cracks growing, water finding its way through crack. That increases rate of growth of the cracks. Add that to your possible sheet piling failure. It just keeps progressing through the structure.

Guillermo Ramirez