现场采用洛氏硬度法判别Q235和Q345钢材种类试验研究

Experimental study on discrimination of Q235 and Q345 steel types by Rockwell hardness method on site

随着无损检测技术迅速发展,采用硬度法现场检测钢材强度越来越广泛,其中洛氏硬度法受到了广泛重视,该方法弥补了里氏硬度法不适用于较薄厚度杆件检测的不足。通过大量洛氏硬度和钢材拉伸强度试验,对试验结果进行统计分析。结果表明,难以用一种模型在洛氏硬度和钢材屈服、抗拉强度之间建立可靠的函数关系;Q235和Q345钢材的里氏硬度和洛氏硬度存在一定的函数关系,可用洛氏硬度法替代里氏硬度法进行钢材检测。通过随机抽样分析,确定了采用洛氏硬度法现场检测的抽样数量,提出了一种采用洛氏硬度法区别钢材种类的评定方法,并给出了洛氏硬度评判Q235和Q345钢材的限值,研究成果可为洛氏硬度法在既有钢结构检测领域应用推广提供可靠支撑,可纳入工程结构领域相关检测技术标准。

With the rapid development of non-destructive testing technology, the use of hardness method to detect the strength of steel in the field is more and more widespread, and Rockwell hardness method has been widely paid attention to. This method makes up for the deficiency that the Richter hardness method is not suitable for the detection of thin bars. Through a large number of Rockwell hardness and steel tensile strength tests, the test results were statistically analyzed. The results show that it is difficult to establish a reliable functional relationship between Rockwell hardness and yield strength and tensile strength of steel with one model. There is a certain functional relationship between the Richter hardness and Rockwell hardness of Q235 and Q345 steels. Rockwell hardness method can be used to replace the Richter hardness method for steel testing. Through random sampling analysis, the sampling quantity of on-site inspection by Rockwell hardness method was determined, an evaluation method for distinguishing steel types by Rockwell hardness method was proposed, and the limit value of Rockwell hardness for judging Q235 and Q345 steels was given. The research results can provide reliable support for the application and promotion of Rockwell hardness method in the field of existing steel structure inspection, and can be included in the relevant inspection technical standards in the field of engineering structure.