Pressure waves crack open sea defences

 作者:滕芘瑟     |      日期:2019-03-06 08:20:01
By Catherine Zandonella SEA walls with cracks and fissures are bound to be undermined by the waves, and now researchers have figured out why some types of cracks do more damage than others. When waves hit a sea wall, they increase the pressure of air and water inside cracks—but this alone didn’t seem to be enough to explain the almost explosive damage to many blocks of sea wall. Air seemed to be the culprit, because cracks above the waterline tend to undermine sea walls, whereas completely submerged cracks do little harm. To work out what was going on,