无粘结部分预应力砼受弯构件的极限强度

Ultimate Strength of Unbonded Prestressed Concrete Flexural Member

通过12块单向板和11根简支梁的试验,分析了无粘结部分预应力砼受弯构件的预应力筋极限应力和极限抗弯强度.试验结果表明,当非预应力有粘结钢筋受拉区截面积的配筋率大于0.4％时,配筋指标和跨高比是影响预应力筋极限应力和极限抗弯强度的主要因素.提出了预应力筋极限应力经验公式,并对无粘结部分预应力砼受弯构件进行了全过程分析,理论分析结果和试验结果符合良好.

Test was performed on 12 one-way slabs and 11 simple supported beams. The stress in the prestressing steel during loading to ultimate and ultimate bending strength of unbonded partially prestressed flexure member are analysed.The test results show that the combined reinforcement index and the radio of span are the main factors which affect the ultimate stress of prestressed reinforcement and ultimate bending strength when steel ratio of the tensile ratio of the rensile region in ordinary bonded steel bar is more than 0.4% affect the ultimate stress of prestressed. An empirical expression for ultimate stress in prestressed streel is proposed. The complete analysis of partially prestressed concrete flexure members have also been provided. The analytical and test results compared in this paper show good agreement.