低温双引伸计法及厚钢板裂纹尖端张开位移δ-J的关系研究  

DOUBLE EXTENSOMETER METHOD AT LOW TEMPERATURE AND THE STUDY OF THE RELATIONSHIP BETWEEN δ AND J OF THICK STEEL PLATE

作　　者：冷树伟[1] 苗张木[1] 姚雪莲[1] 

机构地区：[1]武汉理工大学交通学院,武汉430063

出　　处：《钢结构》2013年第7期24-28,共5页Steel Construction

摘　　要：为了研究低温下裂纹尖端张开位移(δ)与J积分的关系,提出一种较新的试验方法:低温双引伸计法。并且对厚度为40mm,强度为730～770MPa的低合金高强度锚链钢在温度为-20℃的低温环境下进行了低温双引伸计法试验。试验结果表明:低温双引伸计法在高强度钢韧性试验上的应用是成功的,而且具有准确性和经济性的优点;通过试验,对BS7448的公式进行了修正;得到了δ与J的线性拟合曲线,从而建立了在此种强度、温度和厚度条件下该钢的J积分和δ关系的定量公式。同时还讨论了转动因子为0.4和0.45两种情况下,δ值以及δ与J积分关系公式的变化情况。A test method called double extensometer method at low temperature was put forward in this paper to build the relationship between δ and J at low temperature for high strength thick steel specimens. The test has been performed on 730~770 MPa high strength anchor chain steel with thickness 40 mm and temperature at -20 ℃ to obtain the δ and J values at the same time.The results showed that this new method was feasible to determine the δ and J at low temperature; the formula of BS 7448 had been modified through the test results; the linear fitting curve of δ and J was obtained to establish formula. Finally, a discussion about the influence of rotational factor to the δ and J had been made.

关 键 词：裂纹尖端张开位移 J积分 低温 双引伸计 锚链钢 低合金高强钢 

分 类 号：TU511.3[建筑科学—建筑技术科学]