基于船桥碰撞的单元填充式防护结构研究

发布时间：2018-03-22 05:22

本文选题：撞击船舶　切入点：防护装置　出处：《江苏科技大学》2014年硕士论文　论文类型：学位论文

【摘要】：随着世界经济的增长和社会的发展，桥梁建设越来越多，船舶运输也越来越频繁，环境和人为操作失误等因素使船桥碰撞问题研究的迫切性日益突出。本文采用非线性有限元软件ANSYS/LS-DYNA对大型撞击船舶与桥梁发生碰撞的过程进行了数值仿真计算。论文阐述了数值仿真中所用到的关键技术；探讨了船桥碰撞仿真的建模技术和参数选取等问题，并以此为基础，分别建立了船艏-桥梁碰撞的有限元模型，船艏-单元未填充防护装置-桥梁模型，船艏-单元填充防护装置-桥梁模型，然后进行数值仿真，计算分析了碰撞过程中的碰撞力、能量转化以及结构的损伤变形等，并将三种情况下得到的结果进行了比对分析得出相应结论。论文最后讨论了防护装置的设计参数对防护性能的影响，然后对其结构形式进行相关调整，使其具有可拆卸性。本文主要研究工作及结论如下： (1)消化吸收撞击仿真中采用的非线性有限元软件的相关理论及主要方法。 (2)总结归纳防护装置的设计要求和分类方法，并结合实例详细阐述了八种防护装置的工作原理、适用范围及其优缺点和各类防护装置的发展方向，文章将选取缓冲体方式的钢箱结构。 (3)探讨了船桥碰撞仿真中的建模技术及参数选取，采用ANSYS/LS-DYNA有限元软件建立了船艏-桥梁碰撞的有限元模型，对碰撞全过程进行仿真模拟分析。结果表明：当桥梁未设立防护装置时，船舶的撞击动能主要转化为撞击船舶的变形能，桥梁吸收相对较少的能量，但是由于桥梁可抗撞击力相对很小，应对其采取保护措施。 (4)采用ANSYS/LS-DYNA有限元软件建立了船艏-单元未填充防护装置-桥梁模型，对其碰撞过程进行模拟分析，并将得到的计算结果与未设立防护装置情况进行比对分析。结果表示：当桥梁设立普通防护装置时，撞击船舶的总动能主要转化为防护装置的变形能，桥梁所受到的冲击力减少30%左右，桥梁和船舶都受到良好的保护。 (5)运用ANSYS/LS-DYNA软件建立了船艏-单元填充防护装置-桥梁模型，选用三种不同密度的泡沫铝材料作为填充物，对其碰撞过程进行模拟分析，，并将得到的计算结果与设立普通防护装置的情况进行比对分析。结果表示：当泡沫铝作为填充物添加防护装置的单元结构时，其吸能效率会比普通防护装置明显增加，而且密度为0.56g/cm3的泡沫铝相对另外两种密度的泡沫铝能更大限度的提高防护装置的吸能效率。 (6)研究防护装置设计参数对防护装置防撞性能的影响，如：不同撞击位置与不同板厚度，以得到最佳参数，使结构得到优化。得出的结论为：船与装置的变形损伤以正碰最为严重；适当减小防护装置的板厚，但是不允许防护装置的板厚太小。 (7)改进普通防护装置的结构，其单个结构单元采用由钢板拼接而成，角点处和相交边界处进行螺栓锚固形式。数值模拟后发现改进后的防撞装置的防撞性能稍稍优于普通防护装置，但是改进后的装置具有可拆卸性，具有强大的经济效益。
[Abstract]:With the development of world economy and society, more and more bridges, ships are becoming more and more frequent, the environment and human error factors such as the urgency of the problem of collision has become increasingly prominent.
This paper uses the nonlinear finite element software ANSYS/LS-DYNA to process large impact vessel bridge collision is simulated. The paper describes the key technologies used in numerical simulation; discusses the problem of selecting modeling technology and parameters of ship bridge collision simulation, and on this basis, the finite element model of ship - bridge collision establish ship - unit unfilled protection - bridge model, ship - filling unit protection device of bridge model, then the numerical simulation analysis of collision force calculation, energy conversion and structural damage and deformation, and three cases results were compared the corresponding results are obtained. The influence of design parameters on the protective performance of protective device is discussed, and then adjust related to its structure, which has the disassembly. The main research work and conclusions are as follows:
(1) the related theories and main methods of the nonlinear finite element software used in the simulation of absorption and absorption.
(2) summarize the design requirements and classification methods of protective devices. Combined with examples, the working principles, application scope, advantages and disadvantages of the eight kinds of protective devices and the development direction of all kinds of protective devices are elaborated.
(3) discusses the technology of modeling and Simulation of ship bridge collision parameter selection, establish a finite element model of ship - bridge collision using ANSYS/LS-DYNA finite element software, the whole process of collision simulation analysis. The results show that when the bridge has not set up the protective device, the main ship impact energy into the impact deformation of ship can absorb less energy, bridge, but the bridge anti impact force is relatively small, should take protective measures.
(4) a bow - unit unfilled protection - bridge model using ANSYS/LS-DYNA finite element software, the collision process is simulated and analyzed, and the calculation results and did not set up a protective device are analyzed. The results indicated: when the bridge set up general protection device, the total kinetic energy of the ship's main impact into the deformation protection device can impact the bridge, reduced by about 30%, bridges and ships are well protected.
(5) a bow - filling unit protection device - bridge model using ANSYS/LS-DYNA software, using three kinds of different density of aluminum foam as filler, the collision process is simulated and analyzed, and the calculation results and the establishment of common protective device in the comparative analysis. The results showed that when aluminum foam as the unit structure filler material protection device, the energy absorption efficiency will be significantly increased than normal protective device, and the density of aluminum foam 0.56g/cm3 relative to the other two kinds of aluminum foam density can improve the energy absorption efficiency of protection device.
(6) effects of design parameters on the protective device, the anti-collision performance of protective device such as: impact of different position and different plate thickness, in order to obtain the best parameters, the structure has been optimized. The conclusion is that the deformation and damage of ship and the device is to touch the most serious; reduce the protective device of plate thickness, but do not allow the protective device of plate thickness is too small.
(7) improving the structure of common protective device, the single structure unit used by steel plate splicing, corner and boundary of intersection bolt. Find the anti-collision performance of anti-collision device improved slightly better than the common protective device of numerical simulation, but the improved device has a removable, powerful economic benefits.

【学位授予单位】：江苏科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U447;U443.26

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