由于研究的深入和计算技术的发展,钢筋屈服后的应力-应变曲线具有很大的实用价值,因而受到了人们的重视。《钢筋应力-应变特性初步分析》认为,在极限荷重之前,断面没有“缩颈”,应变在试件全长上基本是均匀的,并给出了最大的均匀延伸率值。本文认为,断面的局部收缩在屈服阶段即已产生,它使应变沿长度不均匀,局部收缩区段内的应变较其余区段大。此外,本文还对文献中的其它一些问题提出了补充意见。以往的工作断面收缩可分为三类:一类是沿长度均匀的;一类是沿长度不均匀的,即某处截面上的收缩值要大些,它在钢 Due to the deepening of research and the development of computational techniques, the stress-strain curve after the yielding of steel bars has a great practical value, which has received people’s attention. “Preliminary analysis of the stress-strain characteristics of steel bars” believes that before the extreme load, the section does not “nak the neck”, and the strain is basically uniform over the entire length of the test piece, and the maximum uniform elongation value is given. In this paper, it is believed that the local contraction of the fracture surface has already occurred during the yield phase, it makes the strain along the length non-uniform, and the strain in the local contraction zone is larger than the rest. In addition, this article also provided additional comments on some other issues in the literature. The previous working section shrinkage can be divided into three categories: one is along the length of the uniform; the other is along the length of the uneven, that is, the shrinkage value at a certain point in the section is larger, it is in the steel