Double skin composite beams at Arctic low temperatures: Numerical and analytical studies

Abstract

This paper focused on the developments of numerical and analytical models for double skin composite beams (DSCBs) subjected to low-temperature loadings. Firstly, ten two-point loading tests on DSCBs at varying low temperatures (T) were reported. Followed, a detailed 3D finite element model (FEM) based on ABAQUS was built for simulating ultimate strength behaviours of DSCBs at low temperatures. This FEM fully considered low-temperature influences on material properties, built detailed connector-concrete interactions, and material/geometry nonlinearities. Validations of FEM simulations by ten-test results confirmed the capabilities of the proposed FEM on simulating low-temperature structural behaviours of DSCBs. Parametric studies with 64 cases were performed with the validated FEM to make in-depth investigations on influences of T, steel-faceplate thickness (t), shear span ratio (λ), spacing of headed studs (S), and grade of concrete core (fc). The parametric studies showed that decreasing T from 20 to −80 has significantly improved the ultimate strength of DSCBs; varying shear span ratio (λ = 2.8–5.7) did not change the flexural failure mode of DSCBs; increasing fc marginally changed the ultimate strength behaviour of DSCBs. Corresponding discussions and considerations of these influencing parameters were also given. Analytical models were proposed for estimations of strength and stiffness of DSCBs under low-temperature loadings. Followed validations proved their successful predictions on the strength and stiffness of DSCBs under low-temperature loadings.