Effects of the Arctic low temperature on mechanical properties of Q690 and Q960 high-strength steels. (20th September 2021)

• Record Type: Journal Article
• Authors: Yan, Jia-Bao; Luo, Yan-Li; Lin, Xuchuan; Luo, Yun-Biao; Zhang, Lingxin
• Is Part Of: Construction & building materials. Volume 300(2021)
• Publication Date: 2021-09-20
• Subjects: CC chemical composition -- CFST concrete-filled steel tubular -- COV coefficient of variation -- HSS high-strength steel -- LNG liquid nitrogen gas -- UHPC ultra-high performance concrete; High strength steel -- Q690 -- Q960 -- Low temperatures -- Mechanical properties -- Constitutive model -- Stress–strain curve -- Tensile tests; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2021.124022
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: The Arctic low temperatures improve yield/ultimate strength of HSS Q690/Q960. The HSS Q690/Q960 coupons fail in ductile mode at the Arctic low temperatures. The Arctic low temperatures do not reduce the ductility of HSS Q690 and Q960. Proposed models predict well tensile low-temperature σ-ε curves of HSS Q690/Q960. Abstract: Mechanical properties of high strength steel (HSS) are fundamental information to analyse and design HSS structures. This study extends the applications of HSS Q690 and Q960 to the Arctic infrastructures. The mechanical properties of HSS Q690/Q960 at the low temperature range of −80~20℃ were studied through performing standard tensile tests on 20 HSS Q690 coupons and 19 Q960 coupons in cooling chamber with LNG, which simulated the Arctic low-temperature environment. The influences of low-temperature levels, thickness of HSS plate, and HSS type on mechanical properties of HSS Q690/Q960 were in-depth investigated. The test results showed that the Arctic low temperature increased the modulus, yield and ultimate strength of HSS Q690/Q960, but did not reduced the ductility of these two types of HSS. In addition, all the tensile coupons of HSS failed in ductile mode without brittle fracture. This paper also developed constitutive models for HSS Q690/Q960 at low temperatures of −80~20℃. Validations showed that the developed constitutive models estimated reasonably well mechanical properties of HSS Q690/Q960 at low temperatures of −80~20℃.