建筑结构钢厚板及其连接焊缝Z向性能的试验研究
发布时间：2018-11-28 14:59
【摘要】：伴随着建筑钢结构的巨大发展，钢结构厚板经常应用在高层、大跨建筑，，桥梁，海洋平台，压力容器及船体结构中。随着钢板厚度及焊缝尺寸增加，承受荷载更加复杂，拘束作用更加突出，以及局部地区频繁出现低温，钢结构厚板发生Z向破坏的可能性也越来越大。本文对钢厚板裂纹受厚度方向荷载时的断裂韧性进行了有限元分析，对钢结构厚板及其连接焊缝的Z向性能进行了实验研究，最后提出基于强度和韧性指标的Z向性能钢材选材及设计方法。主要成果如下： （1）对几种典型的厚板及其连接内裂纹进行有限元模拟，对裂纹分布、共生裂纹间距、钢板厚度等加以考虑，分析断裂参数K、J的变化规律，为实际中厚板的断裂分析提供参考。 （2）针对Q345B钢材60~165mm几种不同厚度的钢板，对其母材和十字形焊接连接热影响区，以及对接连接进行取样。取样类型分为沿轧制方向（X向）和厚度方向（Z向），并在-60℃~20℃下进行简单拉伸试验，得到屈服、极限强度f_y、f_u及断面收缩率Z随板厚、焊缝尺寸、取样类型及温度等的变化规律。 （3）针对Q345B钢材60~165mm几种不同厚度的钢板，对其母材和十字形焊接连接热影响区，以及对接连接进行取样。取样类型分为沿轧制方向（X向）和厚度方向（Z向），并在-60℃~20℃下进行夏比V形缺口冲击试验，得到冲击功Akv随板厚、焊缝尺寸、取样类型及温度等的变化规律。 （4）针对Q345B钢材60~165mm几种不同厚度的钢板，对其母材和十字形焊接连接热影响区进行取样。取样类型分为沿轧制方向（X向）和厚度方向（Z向），并在-60℃~20℃下进行三点弯断裂试验，得到断裂韧性指标CTOD值随板厚、焊缝尺寸、取样类型及温度等的变化规律。 （5）在试验基础上，针对现有规范的结构Z向性能敏感性评价标准，修正和补充了基于拉伸力学性能的评价方法，并增加了基于冲击和断裂韧性的评价方法。考虑了温度的影响作用，并针对不同板厚提出具体的敏感指标确定建议。
[Abstract]:With the great development of building steel structures, steel thick plates are often used in high-rise, large-span buildings, bridges, offshore platforms, pressure vessels and hull structures. With the increase of steel plate thickness and weld size, the load is more complex, the restraint effect is more prominent, and the low temperature occurs frequently in the local area, the possibility of Z-direction failure of thick plate of steel structure is more and more large. In this paper, the fracture toughness of thick steel plate under the load of thickness direction is analyzed by finite element method, and the Z-direction behavior of thick plate and joint weld of steel structure is studied experimentally. Finally, the material selection and design method of Z direction performance steel based on strength and toughness index are put forward. The main results are as follows: (1) several typical thick plates and their internal cracks are simulated by finite element method. The distribution of cracks, the spacing of symbiotic cracks and the thickness of steel plate are taken into account. It provides a reference for the fracture analysis of practical plate. (2) for Q345B steel 60~165mm steel plate with different thickness, the base metal, the heat affected zone of cross-welded joint and the butt connection are sampled. The sampling types are divided into the direction of rolling (X direction) and the direction of thickness (Z direction), and the simple tensile tests are carried out at -60 鈩
本文编号：2363210
[Abstract]:With the great development of building steel structures, steel thick plates are often used in high-rise, large-span buildings, bridges, offshore platforms, pressure vessels and hull structures. With the increase of steel plate thickness and weld size, the load is more complex, the restraint effect is more prominent, and the low temperature occurs frequently in the local area, the possibility of Z-direction failure of thick plate of steel structure is more and more large. In this paper, the fracture toughness of thick steel plate under the load of thickness direction is analyzed by finite element method, and the Z-direction behavior of thick plate and joint weld of steel structure is studied experimentally. Finally, the material selection and design method of Z direction performance steel based on strength and toughness index are put forward. The main results are as follows: (1) several typical thick plates and their internal cracks are simulated by finite element method. The distribution of cracks, the spacing of symbiotic cracks and the thickness of steel plate are taken into account. It provides a reference for the fracture analysis of practical plate. (2) for Q345B steel 60~165mm steel plate with different thickness, the base metal, the heat affected zone of cross-welded joint and the butt connection are sampled. The sampling types are divided into the direction of rolling (X direction) and the direction of thickness (Z direction), and the simple tensile tests are carried out at -60 鈩
本文编号：2363210
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