TBM主梁焊接工艺过程数值模拟的研究

发布时间：2018-01-06 15:07

本文关键词：TBM主梁焊接工艺过程数值模拟的研究　出处：《郑州大学》2015年硕士论文　论文类型：学位论文

【摘要】：TBM广泛应用于隧道掘进工程中,主梁作为TBM主机的关键组成部分,承受着刀盘传递过来的力和扭矩,并将其传递到撑靴上,可以说主梁质量的好坏直接影响隧道挖掘的进度和质量。TBM主梁是典型的箱型梁结构,通过焊接制造完成,在焊接完成后不可避免的会产生残余应力及不可忽视的焊接变形,对主梁以及TBM整体的工作性能和使用寿命有着很大影响。以往人们通过试验方法来研究焊接工艺,方法复杂而且消耗较大,进入二十一世纪以来,利用数值模拟的方法对焊接工艺进行研究得到了广泛的开展。本文利用有限元软件ANSYS,选取主梁在实际工况下应力较为集中的部分作为研究对象,并将该部分提取出来建立简化的有限元模型,基于有限元以及热弹塑性等相关理论,对不同的焊接工艺方案进行数值模拟,并得出了温度场、应力场分布变化以及最终的残余应力和变形情况,并加以实验佐证。主要包括以下内容:(1)TBM主梁焊接部位的选取:利用有限元软件ANSYS Workbench对TBM主梁施加实际工作载荷,进行静力学有限元分析,以找出应力较为集中的部分,并以此部分作为焊接工艺的研究对象。(2)焊接数值模拟有限元模型的建立:根据实际焊接工艺,选择主梁顶板与腹板的典型焊接结构作为分析对象,利用有限元软件ANSYS的参数化编程语言建立了包含多层多道焊的焊接部位有限元模型。(3)焊接温度场数值模拟:确定焊接工艺方案和工艺参数,在ANSYS中对焊接过程进行仿真,得到温度场的分布变化规律并分析讨论。(4)焊接应力应变场的数值模拟:通过热-应力耦合的分析流程,以温度场分析结果作为基础,对不同焊接工艺顺序进行模拟,得到应力应变场结果并对比讨论,为实际焊接工艺顺序的选择提供一定的理论基础。(5)采用盲孔法对口字型焊接样件残余应力进行测量,并与数值模拟结果进行对比,以验证模拟结果的合理性,从侧面证明焊接顺序方案选择的合理性。
[Abstract]:TBM is widely used in tunneling engineering. As a key component of TBM mainframe, the main beam bears the force and torque from the cutter head and transfers it to the boot. It can be said that the quality of the main beam directly affects the progress and quality of tunnel excavation. TBM main beam is a typical box girder structure, which is completed by welding. It is inevitable that residual stress and welding deformation can not be ignored after welding is completed. It has a great influence on the working performance and service life of the main beam and the whole TBM. In the past, people studied the welding process through the test method, the method is complex and consuming, since 21th century. The numerical simulation method has been widely used to study the welding process. In this paper, the finite element software ANSYS is used to select the part of the main beam stress concentration in the actual working conditions as the research object. The simplified finite element model is established by extracting this part. Based on the theory of finite element and thermoelastic-plastic, different welding process schemes are numerically simulated, and the temperature field is obtained. The distribution of the stress field and the final residual stress and deformation. The main contents of this paper are as follows: the actual working load is applied to the main beam of TBM by using the finite element software ANSYS Workbench. The finite element analysis of statics is carried out to find out the part where the stress is concentrated, and this part is used as the research object of welding process. The finite element model of welding numerical simulation is established: according to the actual welding technology. The typical welding structure of the roof and web of the main beam is selected as the analysis object. Using the parametric programming language of finite element software ANSYS, the numerical simulation of welding temperature field including multi-layer multi-pass welding is established: the welding process scheme and process parameters are determined. The welding process is simulated in ANSYS, and the distribution and variation of temperature field are obtained. The numerical simulation of stress-strain field of welding is analyzed and discussed: through the thermal-stress coupling analysis process. Based on the results of temperature field analysis, different welding process sequences are simulated, and the results of stress and strain field are compared and discussed. The method of blind hole method is used to measure the residual stress of the zigzag welding sample, and the results are compared with the numerical simulation results. In order to verify the rationality of the simulation results, from the side to prove the rationality of the selection of welding sequence.
【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U455.3;TG44

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