Steel fenders are increasingly used for ship-impact resistance structures in the design of navigable bridges. As an important approach to investigating this anti-impact structure effectiveness to reduce influences of ...Steel fenders are increasingly used for ship-impact resistance structures in the design of navigable bridges. As an important approach to investigating this anti-impact structure effectiveness to reduce influences of vessel impact, simulation analyses are still not perfect yet. So this paper is intended to discuss several issues related to ship collision simulations, including steel constitutive relationship, connections between steel box and pile cap, contacts definition and friction consideration, and the determination of impact waterlines and angles. Consequently based on two examples of ship-steel fender-bridge structure systems, some conclusions about effectiveness and design of fenders to reduce ship impact are drawn.展开更多
In order to describe the thermal–mechanical behavior of the ship plate steel continuous casting slab during solidification end heavy reduction(HR)process accurately,its constitutive behavior was investigated by a sin...In order to describe the thermal–mechanical behavior of the ship plate steel continuous casting slab during solidification end heavy reduction(HR)process accurately,its constitutive behavior was investigated by a single-pass thermal compression experiment.According to the deformation features of wide thick continuous casting slab with HR,the simulation temperature ranged from 1173 to 1573 K with strain rates of 0.0001,0.001,0.01 and 0.1 s^(-1).Three different constitutive models,the modified Johnson–Cook(JC)model,the modified Zerilli–Armstrong(ZA)model and the Arrhenius model,were established according to the obtained true stress–strain curves.The average relative error of the modified JC model,the modified ZA model and the Arrhenius model are 10.82%,9.96%and 6.21%,respectively.Considering the obvious softening effect of the flow curve at a low strain rate,the secondary softening factor under the interaction of low strain rate and the temperature was introduced in the original Arrhenius model.Compared to the Arrhenius model,the modified Arrhenius model error decreased from 6.21%to 4.73%.展开更多
文摘Steel fenders are increasingly used for ship-impact resistance structures in the design of navigable bridges. As an important approach to investigating this anti-impact structure effectiveness to reduce influences of vessel impact, simulation analyses are still not perfect yet. So this paper is intended to discuss several issues related to ship collision simulations, including steel constitutive relationship, connections between steel box and pile cap, contacts definition and friction consideration, and the determination of impact waterlines and angles. Consequently based on two examples of ship-steel fender-bridge structure systems, some conclusions about effectiveness and design of fenders to reduce ship impact are drawn.
基金The present work was financially supported by the National Natural Science Foundation of China(Nos.51974078 and U20A20272)Science and Technology Planning Project of Liaoning Province(Nos.2022JH2/101300002 and 2022JH25/10200003)the Fundamental Research Funds for the Central Universities of China(No.N2125018).
文摘In order to describe the thermal–mechanical behavior of the ship plate steel continuous casting slab during solidification end heavy reduction(HR)process accurately,its constitutive behavior was investigated by a single-pass thermal compression experiment.According to the deformation features of wide thick continuous casting slab with HR,the simulation temperature ranged from 1173 to 1573 K with strain rates of 0.0001,0.001,0.01 and 0.1 s^(-1).Three different constitutive models,the modified Johnson–Cook(JC)model,the modified Zerilli–Armstrong(ZA)model and the Arrhenius model,were established according to the obtained true stress–strain curves.The average relative error of the modified JC model,the modified ZA model and the Arrhenius model are 10.82%,9.96%and 6.21%,respectively.Considering the obvious softening effect of the flow curve at a low strain rate,the secondary softening factor under the interaction of low strain rate and the temperature was introduced in the original Arrhenius model.Compared to the Arrhenius model,the modified Arrhenius model error decreased from 6.21%to 4.73%.