Abstract: On the basis of our test data,this paper studies the influences of unbended tendon,prestressing degree,section shape and concrete strength on the development of flextural cracks of P.P.C.beams,and proposes a mathematic model for predicting the width of flextural cracks.Combined with the existing achievement and statistical analysis on the measured data,a simple and practical formula is put forward for reference.

Key words: crack width, unbonded tendon, cracking moment, ultimate moment

摘要： 本文依据试验资料,研究了无粘结预应力筋、预应力度、截面形式及砼强度对弯曲裂缝开展的影响,提出了一个预测裂缝开展宽度的数学模式,并结合已有研究成果和对实测数据的统计分析,得到了一个简单适用的计算公式,供设计和研究参考。

关键词: 裂缝宽度, 无粘结力筋, 开裂弯矩, 破坏弯矩