含共线等长双裂纹损伤钢构件的力学试验及分析

在实际工程中，钢构件在同一条直线上的多条裂纹共线排列现象，既是一种较为常见的形式，也是最具有危险性的形式。这种共线裂纹可能导致钢构件发生脆性破坏，所以有必要深入研究共线裂纹对钢构件力学性能的影响。以含共线等长双裂纹损伤钢构件为研究对象，展开了单轴拉伸试验，研究了相对裂纹长度和相对裂纹间距对钢构件的断后伸长率、屈服强度和剩余极限强度的影响规律，且在此基础上提出了含共线等长双裂纹损伤钢构件的剩余极限强度计算公式。通过与试验值进行对比分析，本文所提出的剩余极限强度计算公式的相对误差小于1%,验证了本文所提出公式的有效性和准确性。针对含多裂纹损伤钢构件的安全评估，本文提出的剩余极限强度计算公式，在一定程度上弥补了该领域的空白，为其剩余极限强度分析研究提供了一种行之有效的方法，对含多裂纹损伤钢构件后期的预防和修复等具有一定的理论价值和现实意义。

Mechanical test and analysis of damaged steel members with collinear equal length double cracks

In practical engineering, the phenomenon that multiple cracks of steel members are arranged in the same line is not only a common form, but also the most dangerous form. This kind of collinear cracks may lead to brittle failure of steel members, so it is necessary to study the influence of collinear cracks on the mechanical properties of steel members. In this paper, a uniaxial tensile test was carried out for a steel member with collinear equal length double cracks as the research object. The influence of the relative crack length and the relative crack spacing on the elongation after fracture, yield strength and residual ultimate strength of the steel member was studied. On this basis, a formula for calculating the residual ultimate strength of the steel member with collinear equal length double cracks was proposed. By comparing and analyzing with the test values, the relative error of the residual ultimate strength calculation formula proposed in this paper is less than 1%, which verifies the validity and accuracy of the formula proposed in this paper. For the safety assessment of steel members with multi crack damage, the residual ultimate strength calculation formula proposed in this paper makes up the blank in this field to some extent, provides an effective method for the analysis and research of its residual ultimate strength, and has certain theoretical value and practical significance for the prevention and repair of steel members with multi crack damage in the later period.