had been closed by the upper flange. When this formwork was in place. steelfixing and concreting followed in the normal manner so that the whole deck span could be stripped 16 days after the last pour. From the start to the finish a span usually took about 56 days.
In
At the ends of the span adjoining the abutments, the soffit of the deck came very close to ground level. order to overcome the difficulty in striking out formwork in this very tight space the outboard ends of these spans were cast on earth fill, sealed with a 3 in. blinding layer of con- crete. The earth fill was left in place to seal this area and avoid difficulties in keeping such a narrow wedge- shape tidy at a later date.
con-
Apart from the difficulties with foundations. problems during struction were of a minor nature only. As is to be expected, most of the components of the flyover are extre- mely heavily reinforced. Some snags arose with steel-fixing, particularly in the junction of the webs and diaphragm end walls of the cellular spans. Other difficulties arose with the need to compact the concrete around the congested reinforcement and the early setting time of the finely ground cement used.
The granite aggregates tended to produce rather harsh unworkable mixes at low water/cement ratios and these factors necessitated more than
चवलेन
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Close-up showing precast reinforced concrete guardrails
usual care being taken over the mix- ing. placing, and vibration of the concrete. Only crushed granite was used for the fine aggregate in the mixes and no difficulty was experi- enced in obtaining the required mini- mum cube strength of 2,900 lb/sq. in. for the 1:6 mix at 28 days.
Supervision
The design and supervision of the construction of Harcourt Road fly- over was carried out under the direc- tion of Mr. G. J. Skelt BSc (Eng). DIC, AMICE. Acting Government
Civil Engineer of the Hong Kong Public Works Department.
References
1. Continuous Hollow Girder Con- crete Bridges. Portland Cement Association
2. The Structural Engineer Vol. 41 No. 8 Institution of Structural Engineers
3. American Civil Engineering Prac-
tice Vol. 3 Robert W. Abbett 4. British Standard 153: Part 3A:
1954 British Standards Institu- tion.
KURIMOTO Winding Sheath
cuts down cost of prestressed concrete construction.
Prestressed concrete work of posttensioning (Freyssinet or Dywidag) type cost far less where KURIMOTO IRON WORKS' winding sheath is used. Fabricated by coiling a continuous steel strip and lock-seaming the coil joint in four folded layers, KURIMOTO winding sheath is easy to handle and transport, can be readily laid out, and is priced low.
* Small in wall thickness (0.2~0.3 mm) and light in weight (0.11~0.72 kg/meter). * Very rigid and hard to collapse.
* Available in any length limited only by shipping means.
* Elastic enough to bow in a manner suitable for prestressing.
Construction material produced by KURIMOTO IRON WORKS includes large-diameter light-gage steel pipe for use as air ducts in buildings, as void-space forms for concrete placement work.
EININ
Far East Architect & Builder June, 1966
TECH VINNA
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KURIMOTO IRON WORKS, LTD.
Head Office:
Branches:
Cable Address:
Karamono-machi, Higashi-ku, Osaka, Japan
Tokyo, Kitakyushu, Nagoya, Sapporo "KURIHON OSAKA", "KURITETU TOKYO"
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