The Effect Of The Accumulative Damage Model And Residual Stress On The Mechanical Properties Of The Combined Welded Heavy Steel Plates

With the increasing huge complex structures, the combined welded heavy steel plates have become the major bearing capacity members, more reaserch should be done in the aspect of the mechanical properties and the effect of the accumulative damage and the residual stress. As litte relative research has been done, it plays an important and valuable role in the engineering that the research of the mechanical properties of the combined welded heavy steel plates under the monotonic horizontal and low reversed cyclic loading and the research of the major parameters.Based on ABAQUS, the accumulative damage which is made of the UMAT is taken into the consideration of the static and hysterestic analysis of the members.The distribution of longitudinal residual stress and residual stress along the thickness have also been taken into consideration. A lot of work has been done to find out the major parameters which give the biggest effect.Firstly, it's been dicussed the effect of the accumulative damage, distribution of longitudinal residual stress and residual stress along the thickness on the members under the monotonic horizontal loading. Parameter analysis includes width-thickness ratio, thickness and axial compression ratio. Members with accumulative damage have lower stiffness and capacity; Distribution of longitudinal residual stress and residual stress along the thickness have an obvious effect on the stiffness and elastic capacity; With the same width-thickness ratio, the thicker the thickness of the member is, the more obvious effect on static properties is showed with the consideration of damage, distribution of longitudinal residual stress and residual stress along the thickness. All of which is the basement of the hysterestic properties.Subsequently, it's focused on the effect of the accumulative damage on the members'hysterestic properties. Large factors research has been done, such as width-thickness and thickness of the web and flange. Considering accumulative damage, thickness of the web and flange has an obvious effect on hysterestic properties, when width-thickness of the web and flange is in a lower range.In the end, it's worked on the effect of the damage, distribution of longitudinal residual stress and residual stress along the thickness on the members' hysterestic properties. Large factors research has been done, such as width-thickness and thickness of the web and flange. Considering residual stress and lower width-thickness ratio, as the thickness increasing, the percentage of the ductility coefficient reducement is bigger. Considering the accumulative damage and residual stress, thickness of the web and flange has an obvious effect on hysterestic properties, when width-thickness of the web and flange is in a lower range. When thickness is higher than 100 millimeter, as the increasing times of the cyclic loading, the hysterestic loop gets thinner. The stiffness, load-carrying capacity and the ductility coefficient are lower as the thickness being thicker.