Compressive-force path and behaviour of prestressed concrete beams
Tóm tắt
A study of the performance of prestressed concrete beams designed either by conventional design methods or to a physical model proposed in compliance with the ‘compressive-force path’ concept is presented. Results obtained from testing heavily prestressed beams are reported, which show that members designed to the latter concept may be safer than their Code counterparts. The behaviour of these beams has been compared with similar prestressed concrete beams (also designed either to current code provisions or to the proposed method)— but subjected to a smaller amount of prestressing—in an effort to monitor the effect of the level of prestressing on the behaviour of members designed by different methods. In contrast to the current way of thinking, it emerges that an additional amount of prestressing, instead of increasing the shear contribution of concrete, may, in fact, limit the load-bearing capacity of the member itself.
Tài liệu tham khảo
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