（1 土木工程安全与耐久教育部重点实验室，清华大学土木工程系， 北京 100084； 

2 北京交通大学土木建筑工程学院， 北京 100084； 3 鞍钢股份产品发展部， 鞍山 114009）

［摘要］为了了解国产低屈服点钢的生产情况，得到低屈服点钢的材性参数并进一步提出其设计指标，收集到了鞍钢生产的LY100，LY160和LY225低屈服点钢材性数据。数据主要包括屈服强度、抗拉强度、断后伸长率及冲击功等力学性能。对收集到的数据进行了统计分析，并研究了低屈服点钢力学性能的厚度效应。同时考虑了试验加载速率及试验机柔度的影响，最终计算得到LY100，LY160和LY225钢的材料不定性统计参数。材料不定性统计参数将作为下一步计算低屈服点钢构件抗力分项系数的基础，为《低屈服点钢应用技术规程》的编制提供研究依据。

［关键词］低屈服点钢； 力学性能； 统计分析； 加载速率； 试验机柔度

中图分类号：TU391文献标识码：A文章编号：1002-848X(2017)04-0053-05

Statistical analysis of material properties of low-yield-point steels

Shi Gang1, Wang Xun2, Zhang Yong2, Liu Ming3, Wang Xiaoqiang3

(1 Key Laboratory of Civil Engineering Safety and Durability of China Education Ministry, Department of Civil Engineering, Tsinghua University, Beijing 100084, China; 2 School of Civil Engineering, Beijing JiaoTong University, Beijing 100084,  China;  3 Product Development Department, Angang Steel Company, Anshan 114009, China)

Abstract:In order to investigate the production status of domestic low-yield-point steels, obtain the parameters of material properties and present the design values, LY100，LY160 and LY255 steels produced by Angang Steel Company were studied. The main research content contains the data of mechanical properties such as yield strength, tensile strength, percentage elongation and impact work. The collected data were analyzed by the mathematical statistics method. In the meantime, the effects of the thickness on the mechanical properties were researched. Finally the statistical parameters of material uncertainty of LY100, LY160 and LY225 steels were obtained considering the influence of the loading rate and test machine flexibility, which would be used to calculate the partial factors for resistance of low-yield-point steels and provide suggestions for Technical specification for application of low-yield-point steel.

Keywords:low-yield-point steel; mechanical property; statistical analysis; loading rate; test machine flexibility

*国家自然科学基金项目(51478244)，国家自然科学基金优秀青年科学基金项目(51522806)。

作者简介：施刚，教授，博士研究生导师，Email: shigang@tsinghua.edu.cn。