A) THE TSING - MA BRIDGE at 1430m MAIN SPAN (Table No. 4)
(a)
There is only one single link connecting the urban area with the new CLK AIRPORT: the access must be via the world's second longest span TSING-MA BRIDGE. Even after the completion of the bridge, typhoons, drunken captains, accidents or sabotage may render CLK AIRPORT inaccessible. It is rumoured that a fleet of ferries will be kept for just such contingency. In future, any disruption to this bridge will leave CLK AIRPORT stranded. Surely this is not good strategic planning: why force Hong Kong to accept this single access and take the risks unnecessarily? Are there absolutely no other alternatives?
(b) During the construction of the new CLK AIRPORT, except for the last 9 months, no road access will be provided because the TSING - MA BRIDGE is not scheduled for completion until 2Q, 1996. And that schedule is optimistic. As the construction of airport involves multiple-disciplines and literally a cast of thousands, surely the lack of road access will have adverse effects on costs and schedule.
(c)
(d)
The methods and sequence of erection are vital to the schedule and economy in the building of major bridges. Contractors' methods vary widely and their methods have to be taken into account by the designers at the earliest stage. Big bridge contracts these days, therefore, are almost always executed on a turn-key DESIGN + CONSTRUCT basis. In other words, the proof of the pudding is strictly in the eating.
The design of a 1,430m span road + rail bridge in a typhoon infested area such as Hong Kong is at the cutting edge of today's technology. From August, 1990 to the scheduled completion date of June 1996 is only 70 months away. It would require a world record, if not a miracle, to complete the bridge as scheduled. Take the latest example on the series of bridges across the Seto Inland Sea in Japan (spans 1,100m, 990m and 940m): it took the Japanese from 1978 to 1988, exactly 10 years to execute just the construction. And our 70 months is to include the calling of tender, award of contract, design and construction, probably with a Government appointed designer heading the team and the contract let on a conventional basis.
COMPARISON OF WORLD'S MAIN SUSPENSION BRIDGES
Rank
Name of Bridge
Main Span
Country Completion
O
1 Akashi Kaikyo
(m) 1,990
Japan
1998
Bridge
2 Tsing Yi-Ma Wan 3 Humber Bridge
1,430
Hong Kong
1996
1,410
U.K
1981
4 Verrazano-Narrows
1,298
U.S.A.
1964
Bridge
5 Golden Gate Bridge
1,280
U.S.A.
1937
6
Mackinac Straits Bridge
1,158
U.S.A.
1957
O
7 Minami Bisan-Seto
1,100
Japan
1988
Bridge
8 Faith Sultan
1,090
Turkey
1988
Mehmet Bridge
9 Bosphorus Bridge
1,074
Turkey
1973
10 George Washington
Bridge
1,067
U.S.A.
1931
11 3rd Kurushima
Bridge
1,030
Japan
1999
12 April 25th Bridge
1,013
Portugal 1966
o 132nd Kurushima
1,010
Japan
1999
Bridge
14 Forth Road Bridge
1,006
U.K.
1964
o 15 Kita Bisan-Seto
Bridge
990
Japan
1988
o 17
16 Seven Bridge
Shimotsui-Seto
988
U.K.
1966
940
Japan
1988
Bridge
18 Tatara Bridge
890*
Japan
19 Ohnaruto Bridge
876
Japan
1985
20 New Tacoma
853
U.S.A.
1950
Narrows Bridge
21 Innoshima Bridge
770
Japan
1983
0
Double-decked Highway-railway bridge Investigation
TABLE NO. 4
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