基于半刚性连接的石油井架安全承载性能研究  

Safety assessment on the bearing capacity of semi-rigidly connected oil derricks

作　　者：付海龙[1] 邹龙庆[1] 王玥[1] 刘冬[2] 

机构地区：[1]东北石油大学机械科学与工程学院 [2]齐齐哈尔大学机电工程学院

出　　处：《天然气工业》2015年第10期145-150,共6页Natural Gas Industry

基　　金：国家科技支撑计划项目(编号:2012BAH28F00);黑龙江省自然科学基金项目(编号:E201409);东北石油大学青年科学基金项目(编号:ky120221)

摘　　要：焊接是石油钻机井架钢结构主要的节点连接方式。对石油井架结构进行安全评定和仿真计算时,传统上大都按照刚性节点处理,忽略了焊接节点半刚性连接对于井架结构整体承载性能的影响。通过建立半刚性连接的石油井架钢结构节点构造模型,计算焊接节点单元初始刚度,完成了空间框架结构半刚性节点弯矩与转角的力学描述。结合有限元法,运用双向变刚度零长度螺旋弹簧模拟节点半刚性,实现了相同边界条件下刚性和半刚性井架有限元仿真计算。对比结果表明,刚性和半刚性连接对于井架竖向荷载作用下的位移变形与应力影响不大,但横向荷载作用时.计算结果表现出明显的差异性。由此提出,对在役井架承载安全评定时,除考虑竖向荷载外,还应充分考虑风载、管柱靠力等横向荷载作用时焊接节点的半刚性影响。该认识成果为大型钢结构半刚性力学研究和石油井架安全评定提供了新的思路。Welding is an important joint connection mode for steel structures of oil derricks. Conventionally, a rigid joint is adopted for safety assessment and simulation computation of oil derrick structures. In this process, however, the effect of semi-rigid connec- tion of welded joints on the overall bearing capacity of derrick structures is neglected. Thus a structural model was established for semi-rigidly connected steel structure joints of oil derricks to calculate the initial rigidity of a welded joint unit, and then mechanical description was performed of the bending moments and rotation angles on semi-rigid joints of space frame structures. Based on the fi- nite element method, finite-element simulation computation was realized on rigid and semi-rigid derricks with the same boundary conditions by using two-way spiral springs with variable rigidity and zero length to simulate the semi rigidity of joints. Based on com- parative analysis, the displacement deformation and stress are less affected by rigid and semi-rigid connections when it is under the force of vertical load, but quite different when it is under the force of lateral load. Therefore, it was proposed to pay attention to the effect of semi-rigidity of welded joints under the force of not only vertical load, but lateral load （e.g. wind load and pipe string sup- port force）. This finding provides a new concept for the mechanical study on semi-rigidity of large-size steel structures and the safety assessment of oil derricks.

关 键 词：石油井架 半刚性 钢结构 刚度 焊接节点 有限元 承载力 

分 类 号：TU391[建筑科学—结构工程]