Fatigue testing and performance of steel reinforcement bars
Tóm tắt
The methods of testing and the fatigue performance of six types of high strength steel reinforcement have been studied. Effects of bar diameter and butt-welding have been evaluated with an emphasis on long endurances. There is no evidence of the commonly assumed endurance limit at around 2×106 cycles and fractures occurred at up to 97×106 cycles. The performance can be represented by the expression σ
r
9
N=K, where σr is stress range and N is cycles to failure. The value of K is dependent on type of test, bending or axial, and bar diameter. It is concluded that it is appropriate to design using the performance for axial testing in air. The method of expressing performance is uniform with classification of welded connections and gives a safe representation of behaviour.
Tài liệu tham khảo
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Crown Copyright 1983.—Any views expressed in this paper are not necessarily those of the Department of the Environment or of the Department of Transport. Extracts from the text may be reproduced, except for commercial purposes, provided the source is acknowledged.