Earthquake-proof cranes

Sumitomo Mitsui Construction Co. – a Japanese general construction company based in Tokyo – put five Liebherr 42 K.1/J fast-erecting cranes to work on a construction project close to Mount Fuji in the south east of Japan. One reason the Sumitomo Mitsui Construction Co. chose these cranes was their ability to withstand earthquakes, cranes manufacturer Liebherr stated.

The cranes, rented from Cranetal Noda Co., are built to withstand earthquakes scoring level nine on the Mercalli intensity scale and hurricanes of up to 200 km/h. A 2019 article in Hong Kong-based newspaper The South China Morning Post, said the last large earthquake to hit Tokyo was in 1923 and experts estimate the next one is due roughly a century on, with an estimated 70 per cent chance of a magnitude-7 quake hitting Tokyo before 2050. It was no longer a question of if – but when – the big one will come, the paper predicted.

The five fast-erectors were being used to construct the bridge piers and girders of a new motorway linking the city of Toyoda with Japan’s capital Tokyo. The jib length of the cranes is variable between 25.5 to 36 metres, and the tower height from 12 to 26 metres; Liebherr reported that Sumitomo Mitsui Construction Co. found this flexibility of benefit.