中文摘要：

为了克服弹性补偿法每一步计算量太大的问题,结合弹塑性分析法和塑性极限分析法的优点,提出求解复杂结构极限荷载的增量弹性有限元迭代法（IEFEIM）。该方法以荷载因子β为变量,采用自适应增量调整技术,迭代逼近满足平衡条件和屈服条件的最大荷载因子βmax。与弹塑性分析法相比,IEFEIM只需材料的强度准则,不需要材料屈服、破坏后的本构关系;与塑性极限分析法相比,IEFEIM只需增量定向搜索逼近荷载因子最大值,无需开展大范围搜索的规划算法;与弹性补偿法相比,只需形成一次整体刚度矩阵,无需每一步重新形成整体刚度矩阵,可以有效地减少每次迭代的计算量。工程实例表明,IEFEIM可以有效地求得高拱坝的极限荷载,并可以给出临近极限状态时的结构性状。

英文摘要：

In order to avoid large amounts of computation with the elastic compensation method,the incremental elastic finite element iterative method（ IEFEIM） is proposed for solution of the ultimate load of complex structures,based on the advantages of elastic-plastic analysis and plastic limit analysis. With the load factor β as a variable,and by using the self-adaptive increment adjustment technique,the maximum load factor βmaxsatisfying the equilibrium and yield conditions is obtained by iteration and approximation. In contrast to the elastic-plastic analysis method,the IEFEIM only requires the strength criterion of materials and does not require the constitutive relationship of materials after yielding and failure; in contrast to the plastic limit analysis method,the IEFEIM obtains the maximum load factor by directional search and approximation,without using the programming algorithm for large-scale search; and in contrast to the elastic compensation method,the IEFEIM generates the global stiffness matrix for only one time,without any need of generating the global stiffness matrix for each step,effectively decreasing the amount of computation in iterations. Practical application in engineering projects shows that the IEFEIM can obtain the ultimate load of high dams effectively and provide the structural characteristics close to the ultimate state.