Ltd. showed that rock formation was 260 feet below datum level. Profes-
sor
Sean Mackey. Professor of engineering at the University of Hong Kong. was called in as con- sultant.
After investigation and consulta- tion it was decided that there was no alternative but to go ahead with conventional piling equipment be- cause there was no equipment avail- able which would reach that depth. It was known. after the investiga- tions, that there was a "hard pan' at the 60-70 foot level. so it was decided to ask the Vibro Piling Co. Ltd. to drive the piles to this level.
During the pile sinking it was found very difficult to penetrate through the 40 to 45 foot level, where the ground was so hard that at one stage 500 blows of the pile driver succeeded in penetrating only one-eighth of an inch. But suddenly the obstruction was pierced and a solid foundation found at 70 feet. No settlement has occurred since the building was completed.
Another problem during the foundation work was water on the site. This was first encountered at five feet below the road level when extracting the old wooden piles on which earlier buildings had been raised The whole site flooded like a pond, with water entering so quickly that conventional methods previously used in the Colony would not have been able to cope with it. It was decided to use the well point dewater- ing system of the Millars' Machinery Co. Ltd. The four vacuum pumps of the system were kept going at full flow day and night throughout the whole period of foundation work until it was completed and made watertight. The bottom of the foundations is 25 feet below road level and so well below the lowest tide level, so that the pumps operated successfully for six months.
An innovation in bank planning in Hong Kong is that the ground floor has been given over to shops and that the main banking hall of the Bank has been placed on the first floor. Access to the banking hall is by ordinary staircase or by means of two 32-inch escalators.
The 22 floors of the whole build- ing are served by four 2,500 lb. 700 feet per minute high-rise electroni- cally controlled lifts, three 2.500 lb.
92
CONNAUGHT
ROAD
CENTRAL
500 feet per minute low-rise electro- nically controlled lifts. two gearless 500 feet per minute private lifts, one 300 feet per minute lift and two dumb waiters. All are installed by the Otis Elevator Co.
The whole building is air-condi- tioned by a Carrier plant of ap- proximately 700 tons capacity. The system is a chilled water systemn serving 22 zone cabinets and 50 fan- coil units. Automatic temperature controls. in which a thermostat re- gulates the supply of conditioned air. gives maximum comfort conditions. in winter as well as summer. Auto- matic humidity control is provided by the Minneapolis-Honeywell system.
Installation of the whole system involved a total of 3.980 labour days and six engineers were involved in the design and installation.
POWER
Throughout the working spaces and public rooms of the Bank itself illumination is by means of British G.E.C. Infinilite lighting. The active source of light is installed behind a pierced screen so that the effect is of a room illuminated from a luminis. cent ceiling.
Walls and counters in the banking area are faced in grey Italian mar ble.
Floors, and some of the walls, in the bank are covered is 223.000 square feet of Halstead's Polyflor, a P.V.C. flexible floor covering which resists the action of the currently popular stiletto heel.
The building stands on a site of 15,545 square feet bounded by Des Voeux Road Central. Connaught Road Central, Queen Victoria Street and David House.
▼ Basement and ground floor plans.
Z
LAVATORY
YARD
UP
LAVATORY"
STORE
-UP
SHOP
L LIF T
P t TS
AM.
PASSAGE
PATROL
PASSAGE
VAULT
<SAFE DEPOSIT
AIR
CONDITIONING PLANT
SHOP
RAME
OPEN
AREA.
SWITCH RM.
ARCADE
SHOP
EDUC† (ZZIAIR-CONDITIONING DUCTS
QUEEN
VICTORIA
ARCADE
..CUSTODIAN,
VESTIBULE
TFFT]
LAMATORY
*
SHOP
LOT BOUNDARY
STREET
THE HONG KONG & FAR EAST BUILDER
LOBBY
SHOP
LOT
BOUNDARY
ARCADE
ESCALATORS
ENTRANCE
ROAD
CENTRAL
TABOA
- VOLUME 17. NUMBER 5