求海岸腐蚀问题

来源：百度知道 编辑：UC知道 时间：2024/06/09 09:51:50
Your professor has asked me to talk to you today about the topic that should be of real concern to civil engineers: the erosion of US beaches. Let me start with some statistics. Did you know that 90% of the coast in this country is eroding, on the gulf of Mexico for instance, erosion averages 4 to 5 feet per year. Over the past 20 years, there has been an increase in building along the coast, even though geologists and environmentalists have been warning communities about problems like erosion. Someway communities have tried to protect their building and roads and to build seawalls. However geologists have found that such stabilizing structures actually speed up the destruction of the beaches. These beaches with seawalls, called stabilized beaches, are much narrower than beaches without them. You may wonder how seawalls speed up beach loss. The explanation is simple. If the flow of the beaches is gentle, the water energy is lessened as it washes up along the shore. It is reduced even m

根据翻译应该是这样理解吧 水的能量在回到海里应该要得到补偿 在那些有堤坝的地方 沙子没有办法被带入海洋中 因此能量降了过多 所以需要在别的地方找回补偿 所以在没有堤坝的地方会被带走更大量的沙子 而那些没有堤坝的地方远多于那些有堤坝的地方 所以这样进入海洋的沙子反而是要增加的 因此 这样做是加速海岸的腐蚀