【摘要】 针对用于地震碰撞分析的接触单元模型提出了一种改进求解方法。该方法把碰撞问题等效为一个弹簧—振子模型,由振子、弹簧和阻尼器构成。振子的运动过程代表碰撞的压缩和恢复过程。可以通过对运动方程的求解,得到相对压入量、相对压入速度、碰撞力、碰撞持续时间及其相互关系。该求解方法没有像常用求解方法假设压缩过程和恢复过程中耗散能量相等或者相对压入速度绝对值相等,所以可以得到精确解或者无限接近精确解的近似解。在碰撞中能量耗散较小的情况下,Hertzdamp模型常用求解方法得到的结果接近精确解;而当能量耗散较大时,与精确解的差别就比较大。改进算法不论碰撞中能量耗散大或者小,都可以得到无限接近精确解的结果。因此,改进算法比常用算法更具优越性,尤其是对于存在大量能量耗散的地震碰撞问题。更多还原

【Abstract】 To better study the issue,we presented an improved algorithm.In this algorithm,the impact issue is equivalent to a spring-oscillator model which contains an oscillator,a spring and a damper.The oscillator movement represents the compression phase and restitution phase of impact.By solving the motion equation,we got the penetration displacement,penetration velocity,impact force,impact time and their mutual relationship.The solution process did not carriy out the hypothesis that the energy dissipation or absolute speed during the restitution phase is the same as that during the compression phase,which was adopted by common solution methods.Therefore we can get the exact results or approximate results that are infinitely close to the exact results.In the case of small energy dissipation during the collision,Hertzdamp model results obtaind by common solution methods are close to the exact results.When the energy dissipation during the collision is large,the difference between them becomes obvious.Regardless of small or large energy dissipation during the collision,the improved algorithm can obtain the results which are infinitely close to the exact results.更多还原