Deck work in progress. Note Zublin piles and pile cap detail
Bridge No. 4 and berth. Piling for No. 5 berth in place
Bridge No. 4 and structural members of apron wharf to support decking
and was officially opened last month. The present handling capacity of the deep water wharves is approximately 600,000 tons and will nearly double when the whole project becomes operational in 1970/71.
Construction
The chosen site at Bagon Luar, south of Butterworth, was a virtually derelict area. The landward area covers more than 84 acres of mangrove swamp and foreshore.
Subsoil below the estuarine silt con- sists of soft compressible clays and sand in alternating layers of varying thickness. Boreholes were sunk in 1961 with complementary Dutch cone sound- ings and Vane shear tests. These have been supplemented during construction particularly in advance of piling. As dredging spoil on the immediate fore- shore area was too clayey it could not be used for fill in reclamation.
Instead coarse sand fill was obtained by dredging the sandbanks to the south west of the harbour, known as the Great Kra Flats. A total of 1,800,000 cu. yd. was brought by hopper barges from the sandbanks and pumped to the site.
The contract for reclamation was let in December 1963 to allow for the considerable expected settlement (up to 9 ft.). Reclamation was extended up to a line approximately 480 ft. from the wharf face and the dredged slope is about 4:1 to give a high safety factor.
Wharf and access bridge
The total length of the wharf face is 2,929 ft., giving berthing lengths averaging 550 ft. each, with extra space between Berths 1 and 2 at the north and south ends. The transit sheds are each 75 ft. wide and vary in length be- tween 360 ft. and 450 ft. There are 50 ft. wide front aprons to the three southern conventional berths and 65 ft. wide aprons behind the transit sheds.
The two northern container berths have 60 ft. wide front aprons and 55 ft. wide rear aprons. The southern berths are fitted with rails 16 ft. apart to receive three 6-ton portal cranes in the future, and the northern berths are fitted with rails 50 ft. apart to receive mammoth container cranes should these be required later. A single rail track is brought on the wharf to cater for heavy lifts at Berth No. 2, and twin rail tracks serve the rear of the tran- sit sheds.
The wharf structure itself consists of precast reinforced concrete deck units, and in parts prestressed panels,
38
Far East BUILDER, November 1968.
Page 40Page 41