The waves began to break up the ship after it struck a shoal.

Acts 27:39-41

39 At dawn, we(exc) could see land, but the sailors did not recognize the place. However, they could see that there was a bay and a wide area of sand at the water’s edge. They planned that, if it was possible, they would steer the ship onto the beach. 40 So some of the sailors cut the anchor ropes and let the anchors fall into the sea. At the same time, other sailors untied the ropes that fastened the rudders, so that they could steer the ship again. Then the sailors raised the sail at the front/bow of the ship so that the wind would blow the ship forward, and the ship headed towards the shore. 41 But the ship hit a sandbank. The front of the ship stuck there and could not move, and big waves beat against the back of the ship and it began to break apart.