TNAG-0273-FCO40-309-Scheme-for-development-of-container-terminal-at-Hong-Kong-1970 — Page 27

6. DESIGN CRITERIA

Method of Operation

6.1 The layout recommended by the Container Committee in their 1966 Report is shown on Drawing 4 and was based on alongside berths with 30-ton quay cranes, straddle carriers being used to transport the containers within the Terminal. Immediately before and after loading, containers were to be marshalled in an area adjacent to the quay, where they would be stacked 2-high and where empty containers were also to be stored. As a separate operation the containers were to be transported between the marshalling area and the packing-station sheds, which were to be immediately behind the marshalling area. Plann- ing was based on the use of 20-ton containers, measuring 20 ft. x 8 ft. x 8 ft.

6.2

6.3

6.4

6.5

6.6

Berths

6.7

6.8

6.9

It was envisaged that virtually all the cargo would be packed into and unpacked from containers at the Terminal and that transport of most of the goods between the Terminal and the rest of the Colony would be by lorry in the first instance. It was assumed that the Cross Harbour Tunnel would be available for traffic to Hong Kong Island, but that road congestion would eventually require all goods bound for the Island to be transported by lighter.

These criteria have been discussed with the Container Committee and in the light of develop- ments since 1966 have in some respects been modified. For instance, 40-ft.-long 30-ton containers are now in use throughout the world as well as 20-ft. containers and in some places 20-ft. containers are lifted in pairs. The Container Committee has as a consequence now recommended that the lifting capacity of quay cranes at the terminal should be 50 tons to allow for these developments and for the probable use in the future of even heavier containers. In spite of international efforts to standardise on the 8 ft. x 8 ft. cross section for containers, some 8 ft. wide × 8 ft. 6 in. high containers are still in use and this size will probably also have to be handled in Hong Kong and must be allowed for.

The method of stacking containers 2-high in marshalling areas is widespread in container ports throughout the world but in some places, less area is used by stacking them one on top of the other 5-high. Equipment is also available for storing containers in multi-storey racks to much greater heights with the use of lifts.

Interest has been expressed by stevedoring companies in transporting goods by lighter to and from the Terminal as soon as it comes into operation. It is likely therefore that there would be more demand for the transport of goods by this method in the initial stages than was anticipated in 1966, though the exact demand cannot be forecast and the con- struction of the Cross Harbour Tunnel would also influence this.

Interest has also been shown in transporting containers to and from packing stations remote from the Kwai Chung Terminal as well as to and from the factories that would have large enough loads for whole containers. This interest has been in transporting these both by road and by converted vehicle ferry.

The Container Committee recommended in 1966 that berths should be suitable for con- tainerships of up to 750 ft. in length, with a 100-ft. beam and 33-ft. draught. However because of developments since then, the Committee has since suggested that for the purposes of this engineering report, provision should be made for ships of up to 810-ft. length and 33-ft. draught. The adoption of these criteria involve providing a minimum depth of water of 35 ft. in the approach channel and at the berths, but the Committee has also recommended that the design of quaywalls should permit future dredging to give 40 ft. of water alongside to allow for its possible future use by deeper-draught ships.

Since this recommendation was made, news has been received of a proposal to build 950-ft. long containerships, which could visit Hong Kong. These would have a beam of 106 ft. and a draught of 35 ft.

Because of limitations in the strength of containers, it is not feasible to increase greatly the depth of containerships using the present method of stowing containers one on top of the other in cells. To increase the capacity of containerships by increasing their depth, it would be necessary to introduce 'tween decks and this in turn would require mechanical

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