ELASTIC MODULUS REDUCTION METHOD FOR THE UPPER BOUND OF ULTIMATE BEARING CAPACITY OF STRUCTURES

A numerical solution procedure is presented for the upper bound of ultimate bearing capacity of structures based on the elastic modulus reduction method (EMRM) and the reference volume method. The element bearing ratio (EBR) is developed based on the generalized yield criterion, and is taken as the governing parameter in the process of modulus reduction. The reference EBR is presented by means of the degree of uniformity (DOU) of the EBR. The modulus adjustment strategy is proposed based on the principle of strain energy transformation and energy conservation. A series of kinematic admissible displacement fields are obtained when the damage process of structure is simulated by the iteration process. The reference volume method is introduced to acquire the upper bound of limit load. While inheriting the merits of simplicity and practicality of the elastic modulus adjustment procedures, the method proposed can improve the computational efficiency and enlarge the range of application. Numerical examples show that it is feasible and efficient in limit analysis of complex structures.