基于振动测试参数的井架钢结构极限承载力预测  

Ultimate bearing capacity prediction of derrick steel structures based on dynamic measurement parameters

作　　者：韩东颖[1] 周国强[2] 李子丰[1] 时培明[1] 

机构地区：[1]燕山大学,秦皇岛066004 [2]东北石油大学秦皇岛分校,秦皇岛066004

出　　处：《振动与冲击》2011年第1期106-110,共5页Journal of Vibration and Shock

基　　金：燕山大学博士基金项目(B347);河北省自然科学基金(F2008000882 )

摘　　要：提出了基于振动测试参数预测井架钢结构极限承载力的两种新方法。第一种方法是针对井架钢结构的结构形式和受力特征,将其简化为简支梁,由载荷与振动频率之间的关系,推导出振动频率直接确定极限承载力的简易表达式。该力法简单易行,不需要建立系统的模型。第二种方法是应用一阶搜索优化算法修正动力有限元模型,然后进行线性屈曲、几何非线性和双重非线性分析从而确定井架钢结构的极限承载力,这种方法计算复杂些,但提高了预测准确度。最后利用近似平稳随机激励,对某型号井架钢结构进行了振动参数测试,分别应用这两种方法对极限承载力进行了预测。结果表明这两种基于动力参数的预测值相差不大,均能真实预测井架钢结构的极限承载性能,为复杂承载钢结构的极限承载力预测和安全评估开辟了新途径。In order to predict ultimate bearing capacity of derrick steel structures, two novel methods were proposed based on dynamic parameters identified from vibration measurement. Firstly, aiming at design features and force characteristics of a derrick steel structure, it was simplified as a simply supported beam. According to the relation between load and frequency, the expression for ultimate bearing capacity determined with frequency was deduced. This method was easy and feasible and the system model was not necessary to be built. The first order optimization was used for updating the dynamic model with the second method, and then the linear buckle, nonlinear and double nonlinear analysis were carried out to evaluate the ultimate bearing capacity. The second method was more complex, but accuracy. At last, the dynamic test of some type of derrick steel structures was performed using approximate stationary random motivation. The ultimate bearing capacity was obtained using the two mentioned methods. The resuhs showed that the relative error between the results of two methods is small, so the ultimate bearing capacity can be predicted with these two methods. These two methods also offered an effective way to ultimate bearing capacity prediction and safety evaluation of complex steel structures.

关 键 词：井架钢结构 振动测试 有限元模型 优化 极限承载力 

分 类 号：O329[理学—一般力学与力学基础] TE923[理学—力学]