'Skyhooks' at 18 Foot Centres: Strengthening a Precast OPC/HAC Concrete Frame at Hattersley Heaton,
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'Skyhooks' at 18 Foot Centres: Strengthening a Precast OPC/HAC Concrete Frame at Hattersley Heaton,

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The Structural Engineer
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The Structural Engineer, Volume 74, Issue 1, 1996

Date published

N/A

Citation

The Structural Engineer, Volume 74, Issue 1, 1996

Price

Standard: £10 + VAT
Members/Subscribers: Free

A two-storey precast concrete framed ofice block dating from the 1960s was found to have high alumina cement (HAC) concrete beams at roof and first-floor levels. Detailed investigation showed that the first-floor beams were satisfactory but those at roof level could not be proved. In addition, problems were found with first-floor corbel details and the precast frame beam-column joints. Because the ground floor area had to remain in use during repairs and also the foundation conditions were poor; the roof
was strengthened from above using ‘skyhooks’ - steel beams placed over it and preloaded to limit stresses in the HAC beams. The first-floor corbels were strengthened by drilled-in prestressed bars.

A.N. Beal

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The Institution of Structural Engineers

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