考虑流体效应的船-桥碰撞数值模拟法研究

NUMERICAL SIMULATION METHOD FOR SHIP-BRIDGE COLLISION CONSIDERING FLUID EFFECT

有别于传统的不考虑流体对被撞桥墩影响的船-桥碰撞问题,该文在动水压力计算的基础上,建立了考虑流体效应的船-桥碰撞的附加质量计算模型,并与流构耦合计算模型以及不考虑流体影响的计算模型在能量转换、碰撞力、船艏撞深、桥墩位移、应力、截面内力以及计算效率等方面的结果进行了比较分析。结果表明:流体对船艏碰撞力影响较小,但能降低船舶的损毁程度;流构耦合计算模型中的墩顶水平位移响应要略小于附加质量模型和不考虑流体影响时的计算结果;不同计算模型所得桥墩有效应力基本相同且具有相同的分布规律;船-桥碰撞附加质量模型在计及流体与结构相互作用的同时,具有较高的精度和计算效率。

Different from the traditional analytical method for ship-bridge collision without considering the effect of fluid on the pier impacted, an additional mass model for ship-bridge collision considering the effect of fluid was proposed. Some comparative analyses among the calculation results of the three kinds of models, an additional mass model, a fluid-solid coupling model, and a model without considering the fluid effect, are carried out on the energy conversion, including the collision force, the ship bow＇s penetration depth, the pier＇ displacement, the pier＇s stress, the pier section＇s internal force, and the computational efficiency. It is concluded that the fluid has a smaller effect on the impact force of ship bow, but can make the ship＇s damage extent decrease. The horizontal displacement response of the pier top of a fluid-solid coupling model is slightly less than the results of the other two models. There are roughly the same effective stresses of the pier worked out from different models, which moreover show the similar distribution. The additional mass model used for the ship-bridge collision analysis can not only reflect the interaction between the fluid and the pier, but also have higher computational accuracy and efficiency.