伦敦是一个古老的城市,房屋的修缮任务很重但由于楼房栉次鳞比,空旷的场地较少,因此,在修缮时充分利用有限的空间,保护环境卫生就十分重要。我在伦敦访问时看到房屋修缮,都使用一种渣土管道(图1),清除垃圾。它由多节直径约1米的塑料管组成,由于 London is an ancient city. The repairing tasks of the houses are very heavy. However, due to the scale of the buildings and the empty spaces, it is very important to make full use of the limited space during the renovation and to protect the environment. When I visited London, I saw a house repair, using a dirt pipeline (Figure 1) to remove the garbage. It consists of multi-section plastic tubes with a diameter of about 1 meter, due to