TNAG-0273-FCO40-309-Scheme-for-development-of-container-terminal-at-Hong-Kong-1970 — Page 29

6.17 With 810-ft. instead of the 750-ft. containerships now being considered for this Terminal, the number of containers per ship would be approximately 1,200. This means that if one third of the shipload is still to be handled, provision should now be made for about 400 20-ft. containers in and 400 out for each ship and that enough space should still be left for storing 400 empty containers. To offset this increase in area required, the space and facilities for repairing containers previously recommended (see Drawing 4) should be sited away from the marshalling areas as is common practice in other ports. This would not only make additional area available in the marshalling yard but also would facilitate the necessary movement of containers.

6.18

6.19

With the recommended method of storing containers 2-high on the marshalling area, straddle carriers would be used to transport 20-ft. containers over the 2-high stack and, in sorting operations, might occasionally leave a container on top of it. The design of the marshalling-area surfacing should therefore allow for this loading as well as that produced by the straddle-carrier traffic.

Because of considerations of the stability of the straddle-carriers and of the possible damage to containers during lifting operations, the fall for the surface drainage of the marshalling area should not be steeper than 1 in 70. Containers when landed rest on metal pads at each corner which project downwards and keep their undersides just above ground. This means that the surface of the marshalling area must be uniform enough to avoid touching and possibly damaging the container body. When containers are stacked 2-high, it is necessary to provide some means of securing them so that they are not blown about in typhoons; this applies especially to the empty ones.

The capacity of a marshalling area of given size can be greatly increased if containers are stacked more than 2-high, but because of their limited strength they can only be stacked on top of each other to a maximum of 5-high. Stacking as high as this would require piled foundations for each stacking point on the reclamation and wind walls around the stacks. A gantry crane for placing the containers in the stack and vehicles for transporting the containers between the quayside and marshalling area would also be needed. Sorting containers into different categories of size, weight, destination etc. for correct order of loading would in this case be difficult, but could be achieved by computer control of the operations. Higher stacking and therefore still more intense use of land could be achieved by the use of multi-storey racks with lifts; this equipment is however very expensive and its use could only be justified where insufficient space is available for other methods of stacking.

Packing Stations

6.21 In 1966 the Container Committee recommended that a packing station with a balanced modular layout should be provided for each berth. This station would include space for packing sheds with container- and lorry-loading bays and for a lorry-waiting area with sufficient room for traffic circulation.

6.22

6.23

The proposed packing stations were to be sited immediately adjacent to the marshalling areas and were intended to have sufficient capacity to handle the full throughput of each berth. In an average working day of 12 hours, the throughput capacity was estimated to be 12,000 tons i.e. 300 containers packed and 300 unpacked. The maximum daily throughput capacity with a longer working period was estimated as 20,000 tons i.e. 500 containers each way. This throughput would be obtained using sheds of 18,700 sq. yd. floor area for each berth. The proposed modular layout allowed for storage floors being constructed above the packing floors if needed and these would be served by lifts.

The modular layout allowed a width of 36 ft. on one side of each packing shed for straddle carriers carrying 20-ft. containers. With the 40-ft. containers now envisaged, this width would have to be increased slightly.

6.24 The Container Committee has now agreed that if this study shows there to be any engineer- ing advantage in siting the packing stations away from the marshalling areas in a revised layout for the Terminal, this would be acceptable but the distance away should be kept to a minimum.

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