tailieunhanh - IELTS Academic Reading Sample 124 - Airports on Water

Tài liệu tham khảo IELTS Academic Reading Sample 124 - Airports on Water dành cho các bạn chuẩn bị bước vào kì thi quốc tế, tài liệu giúp các bạn nắm vững các kiến thức căn bản và có thêm nhiều kĩ năng khi làm bài để đạt được thành tích cao, đồng thời giúp ích cho bạn trong công việc tương lai. | AIRPORTS ON WATER River deltas are difficult places for map makers. The river builds them up the sea wears them down their outlines are always changing. The changes in China s Pearl River delta however are more dramatic than these natural fluctuations. An island six kilometers long and with a total area of 1248 hectares is being created there. And the civil engineers are as interested in performance as in speed and size. This is a bit of the delta that they want to endure. The new island of Chek Lap Kok the site of Hong Kong s new airport is 83 complete. The giant dumper trucks rumbling across it will have finished their job by the middle of this year and the airport itself will be built at a similarly breakneck pace. As Chek Lap Kok rises however another new Asian island is sinking back into the sea. This is a 520-hectare island built in Osaka Bay Japan that serves as the platform for the new Kansai airport. Chek Lap Kok was built in a different way and thus hopes to avoid the same sinking fate. The usual way to reclaim land is to pile sand rock on to the seabed. When the seabed oozes with mud this is rather like placing a textbook on a wet sponge the weight squeezes the water out causing both water and sponge to settle lower. The settlement is rarely even different parts sink at different rates. So buildings pipes roads and so on tend to buckle and crack. You can engineer around these problems or you can engineer them out. Kansai took the first approach Chek Lap Kok is taking the second. The differences are both political and geological. Kansai was supposed to be built just one kilometer offshore where the seabed is quite solid. Fishermen protested and the site was shifted a further five kilometers. That put it in deeper water around 20 meters and above a seabed that consisted of 20 meters of soft alluvial silt and mud deposits. Worse below it was a not-very- firm glacial deposit hundreds of meters thick. The Kansai builders recognized that settlement was .