No_4_April_1969 — Page 36

Jacked onto traveling bogies.

Lifted to deck level

by lifting towers

(A)

(B)

Transferred to traversing bogies

at deck level and moved to bridge

centre line. Then transferred to travelling bogies. (Marine spans only)

(C)

Launched into new spen

on the truss gerder.

(Marine spans only)

Traversed to position in

the spa

Final position.

Fig. 4. Handling of precast beams

of bridge

Direction of travel

(F)

(D)

(E)

Direction of travel

winch

Air receiver

allow free ingress of water into the shutter at high tides and thus reduce its buoyancy.

Concrete was hauled manually from a batching plant set up for the purpose near the existing sea wall across a temporary bridge extending progres- sively from pile cap to pile cap as each was cast. The time taken to place concrete in each cap was approximately 12 to 13 hours.

Superstructure

The structure was designed to carry BS 153 HA loading. Wind loads did not affect the design.

The decisive factors influencing the length of spans for the section of bridge crossing the bay were the exist- ing sea wall and the road running along it and forming the access to the new housing development. A span of 93ft. was needed to ensure that no pile fouled the rubble mound founda- tion of the sea wall and, at the same time, to provide adequate clearance for the road. This span fitted well into the full width of the bay and, to main- tain uniformity of elevation, it was decided to continue with the same for the section of bridge between the sea wall and the intermediate ramps.

One of the design requirements was that the main ramp at the eastern end should start west of Po Lun Street and, allowing a gradient of 1 in 20, the construction depth of the land spans had to be restricted to accommodate a ground-level road under the second span out. An analysis suggested a span of 63ft. and this also proved a suitable grid module for a proposed bus terminus to be built under the bridge.

'A'

bolts (2 No. 6′′-14′′R.S.J.

ELEVATION

-3′′6′′st.channel.

Timber packing.

F't bolts

\\731b_rais

2′′h bolts 3′′-6′′steel channel

-2′′a bolt

Fig. 5. Transportation of beam

BEAM

/9′46′′Timber

Beam on bogies moving across steel erection girder

Far East BUILDER, April 1969