The news of the 30-metre-wide “hole” bolting that had opened in a Fukuoka street in Japan on November 8 had made the web tour as an example of Japanese engineering efficiency.
But in the last days the stretch of asphalt in which the synkhole had been created has given new signs of collapse. During the weekend part of that route was closed to traffic (and then reopened) after the authorities found that the ground had collapsed 7 cm in an area of 30 square meters, at the ancient sinkhole
Phenomenon expected. A consequence of badly-made jobs? It seems not. Although the mayor apologized to the citizens for not having felt the possible inconvenience, the workers had calculated that the mixture of soil and cement used to fill the hole could compress the ground below, causing an additional, contained subsi
The 30-metre-x27-metre-wide and 12-metre-deep sinkhole had been caused by the work for the extension of an underground line and had not caused injury. The work on closing it lasted only 48 hours, although the route reopened after a week, on November 15, after the due checks.