Abstract: In order to improve the precision of simulation and reduce the discrepancy between the theoretical calculation and testing result,the model for analysis of the in-service rig derrick was established on the basis of the finite dynamic model using optimization method.Based on a simple and applicable method for sensitivity analysis,the updating parameters were determined such as material,cross shape and size of the main loading rods in the rig derrick.The optimal updating function was established according to the residual differential value between testing modal parameter and theoretical modal parameter.The first-order optimization algorithm was used to optimize and assess the updating parameters.The simulation analysis on an in-service rig derrick was carried out using the linear buckling,geometric nonlinear and double nonlinear methods.The result proves that the calculation of modified model based finite element model is close to the test result.This method is favorable for the forecast of bearing capacity and safety evaluation of rig derrick in the practical engineering.

Key words: rig, derrick, force-bearing capacity prediction, finite element model, modal parameters, updating function, simulation model

摘要： 为改善在役钻机井架仿真建模的精度,减小理论模型计算结果与试验结果之间的偏差,利用优化原理,基于有限元动力模型,建立了在役钻机井架仿真分析模型.依据简单实用原理,利用灵敏度分析方法确定了井架结构主要承载杆件的材料、截面形状和几何尺寸为待修正参数;以试验模态参数和理论模态参数之间的残差最小值构建优化修正函数,利用一阶搜索优化算法对待修正参数进行了优化和状态评估.以某型号在役钻机井架为例,利用该方法并结合线性屈曲法、几何非线性法、双重非线性法,对其进行了仿真建模和承载性能仿真分析,确定了该钻机井架的极限承载力、破坏形式及危险部位.仿真结果表明,经过修正后的有限元计算模型的计算结果与实验结果非常接近.说明该方法适合于对在役钻机井架的承载力预测和安全评估.

关键词: 钻机, 井架, 承载力预测, 有限元模型, 模态参数, 修正函数, 仿真模型