Rigid Frame Bridges in Reinforced Concrete. Discussion on Mr. A.P. Mason's Paper
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Rigid Frame Bridges in Reinforced Concrete. Discussion on Mr. A.P. Mason's Paper

The Structural Engineer
Rigid Frame Bridges in Reinforced Concrete. Discussion on Mr. A.P. Mason's Paper
Date published

N/A

First published

N/A

Price

Standard: £9 + VAT
Members/Subscribers: Free

Buy Now

Mr. M. N. RIDLEY, M.Inst.C.E. (Member of Council), proposing a vote of thanks to the author, welcomed the paper, particularly because it indicated the extent to which continuity in reinforced concrete work was being adopted. He had noticed that engineers were inclined to make pin joints in their bridges. They would put a pin joint in the centre of the arch and pin joints in the abutments, and he believed that in one or two cases there were as many as five. He had always maintained, however, that. a bridge of ordinary span was far safer and better, and sometimes more economically designed, if all pin joints were excluded. It was true that calculation was then more difficult, but he held that when that had been done one had the best type of work. Where there were very big spans, of course, one must consider pin joints or the equivalent, especially for expansion and contraction; but for shorter spans, at any rate up to 100 ft. and sometimes more, in reinforced concrete and steel work pin joints were quite unnecessary.

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