基于灵敏度矩阵特征值的索杆张力结构主动张拉索优选方法

发布时间：2018-09-12 13:57

【摘要】：施工时合理选择主动张拉索是控制索杆张力结构预张力偏差的主要措施。以单元的预张力偏差平方和作为评价整体结构预张力偏差的指标,通过对反映单元预张力偏差与索长误差关系的灵敏度矩阵进行谱分解,将该指标表示为索长误差与灵敏度矩阵的特征值和特征向量的解析关系式,理论上解释了选择不同主动张拉索会使灵敏度矩阵特征值发生变化,从而直接影响到对结构预张力偏差的控制效果。由于灵敏度矩阵特征值具有衰减迅速的特点,故采用其一阶特征值和特征向量可有效估计结构的最不利预张力偏差。进一步以灵敏度矩阵的一阶特征值为评价指标,基于遗传算法提出了一种主动张拉索的优选方法。以一实际索杆张力结构为例,进行不同条件下的主动张拉索优选分析,其结果验证了优选方法的有效性。
[Abstract]:Rational selection of active tension cables is the main measure to control the pretension deviation of cable-bar tension structures. The square sum of pretension deviation of element is taken as the index to evaluate the pretension deviation of whole structure. The sensitivity matrix reflecting the relationship between element pretension deviation and cable length error is decomposed by spectrum. The index is expressed as the analytic relation between the cable length error and the eigenvalue and eigenvector of the sensitivity matrix. It is theoretically explained that the eigenvalue of the sensitivity matrix can be changed by choosing different active tension cables. Therefore, the control effect of the pretension deviation of the structure is directly affected. Because the eigenvalue of the sensitivity matrix has the characteristic of fast attenuation, the first order eigenvalue and eigenvector can be used to estimate the most unfavorable pretension deviation of the structure. Taking the first order eigenvalue of the sensitivity matrix as the evaluation index, an optimal selection method of active tension cables is proposed based on genetic algorithm. Taking an actual cable tension structure as an example, the optimal selection of active tension cables under different conditions is analyzed. The results show that the optimal selection method is effective.
【作者单位】：浙江大学空间结构研究中心;
【基金】：国家自然科学基金项目(50978226) 温州市科技计划项目(S20120001)
【分类号】：TU399

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