March_1971 — Page 13

world news

High-rise building in Osaka

A rush of high-rise construction is sweeping major Japanese cities like Tokyo and Osaka where a radical redevelopment of land is urgently needed to cope with overpopulation, industrial hazards and other environmental problems. In these cities the construction of high-rise buildings is apparently the only solution to the acute lack of land space caused by an over-concentration of population and industry.

More than 20 buildings taller than 100 metres are expected to mushroom in Osaka alone in the coming few years. Tallest of these will be a new main office building for Ohbayashi-Gumi Ltd., the contractors, and the new Osaka International Building being built for Unitica Co. by Takenaka Komuten. Both will have 32 storeys and will reach 120 metres.

In the Ohbayashi Building the main structural members will be of steel, but to improve earth- quake resistance, the most important problem in building skyscrapers in Japan, a new structural

method called the Ohbyashi Cross Structure (OCS) system is being used.

By this method a steel-plate, earthquake-resis- tant wall is combined with a girder to ensure added safety as well as to reduce the amount of steel re- quired.

An unusual feature of the building will be the elevators which will have two-floor cages travelling at the same time. The upper cage stops at the even- number floors and the lower cage at odd-number floors.

Air-conditioning and hot water supply facilities are designed to employ heat-recovery pumps, heat- ed by electricty and partially by city gas, not heavy oil, to minimise air-polution.

The Ohbayashi Building will have three floors below ground and will take up 1,367 sq. metres of a 4,995 sq. metres site. Its total floor area will be 50,292 sq. metres.

International Building

The Osaka International Building, also with three basement floors, will have a total space of 65,400 sq. metres. It is due for completion in 1973 at a cost of about US$20 million.

Thick H-shaped steel will be used for the columns and special honey-comb units for the beams. Computers will be used to control and ad- just the entire building process and the moving of construction materials.

The building will feature white aluminium cur- tain walls for the upper storey office rooms will occupy the third to 31 st. floors, with the 17th, 18th and 32nd set aside for restaurants, tea rooms and meeting rooms. The ground floor and base-

11

Hommachi commercial district with proposed Osaka International Building Superimposed

Far East BUILDER, March 1971

7