Single Shear Bolted Connection Tests of G500 1.20mm Thin Sheet Steel At Elevated Temperatures

The current design rules on bolted connections of thin sheet steels for cold-formed steel structures are applicable for ambient temperature condition only. Research on such kind of connections at high temperatures is limited. In this study, 47 single shear bolted connection specimens fabricated from G500 1.20mm thin sheet steel and 9 coupon specimens were conducted by using steady state test method in the temperature range from 22ºC to 900ºC. Two failure modes were observed in the single shear bolted connection tests, namely the net section tension, and bearing . The test results were compared with the predicted values calculated from the American, Australian/New Zealand and European specifications for cold-formed steel structures. In calculating the nominal strengths of the connections, the reduced material properties were used due to the deterioration of material at elevated temperatures. It is shown that the strengths of the single shear bolted connections predicted by the specifications are generally conservative at elevated temperatures . Furthermore, the comparison between the deterioration of the strengths of connections and that of the material properties due to high temperatures showed a similar tendency of reduction

Single Shear Bolted Connection Tests of G500 1.20mm Thin Sheet Steel At Elevated Temperatures

The current design rules on bolted connections of thin sheet steels for cold-formed steel structures are applicable for ambient temperature condition only. Research on such kind of connections at high temperatures is limited. In this study, 47 single shear bolted connection specimens fabricated from G500 1.20mm thin sheet steel and 9 coupon specimens were conducted by using steady state test method in the temperature range from 22ºC to 900ºC. Two failure modes were observed in the single shear bolted connection tests, namely the net section tension, and bearing . The test results were compared with the predicted values calculated from the American, Australian/New Zealand and European specifications for cold-formed steel structures. In calculating the nominal strengths of the connections, the reduced material properties were used due to the deterioration of material at elevated temperatures. It is shown that the strengths of the single shear bolted connections predicted by the specifications are generally conservative at elevated temperatures . Furthermore, the comparison between the deterioration of the strengths of connections and that of the material properties due to high temperatures showed a similar tendency of reduction

Finite Element Analysis of Cold-formed Channel Columns

The paper presents a numerical investigation into the behaviour and strengths of cold-formed plain and lipped channel columns using finite element analysis. A non-linear finite element model is developed and verified against the fixed-ended channel column tests conducted by Young and Rasmussen (1998a, 1998b and 1998c). Geometric and material non-linearities were included in the finite element model. It is demonstrated that the finite element model closely predicted the ultimate loads and the behaviour of the tested cold-formed channel columns. Hence, the model was used for an extensive parametric study of cross-section geometries. Furthermore, the results of the numerical investigation are compared with the design column strengths calculated using the Australian/New Zealand (1996), American (1996) and European (1996) specifications for cold-formed steel structures. It is shown that the design column strengths calculated from the three specifications are generally conservative for plain and lipped channels having maximum plate thickness of 6.0 mm

Transition metal oxides for high performance sodium ion battery anodes

Sodium-ion batteries (SIBs) are attracting considerable attention with expectation of replacing lithium-ion batteries (LIBs) in large-scale energy storage systems (ESSs). To explore high performance anode materials for SIBs is highly desired subject to the current anode research mainly limited to carbonaceous materials. In this study, a series of transition metal oxides (TMOs) is successfully demonstrated as anodes for SIBs for the first time. The sodium uptake/extract is confirmed in the way of reversible conversion reaction. The pseudocapacitance-type behavior is also observed in the contribution of sodium capacity. For Fe2O3anode, a reversible capacity of 386 mAh g-1at 100 mA g-1 is achieved over 200 cycles; as high as 233 mAhg-1is sustained even cycling at a large current-density of 5 A g-1

Higher moment singularities explored by the net proton non-statistical fluctuations

We use the non-statistical fluctuation instead of the full one to explore the higher moment singularities of net proton event distributions in the relativistic Au+Au collisions at $\sqrt{s_{NN}}$ from 11.5 to 200 GeV calculated by the parton and hadron cascade model PACIAE. The PACIAE results of mean ($M$), variance ($\sigma^2$), skewness ($S$), and kurtosis ($\kappa$) are consistent with the corresponding STAR data. Non-statistical moments are calculated as the difference between the moments derived from real events and the ones from mixed events, which are constructed by combining particles randomly selected from different real events. An evidence of singularity at $\sqrt{s_{NN}}\sim$ 60 GeV is first seen in the energy dependent non-statistical $S$ and $S\sigma$.Comment: 5 pages,5 figure