中文摘要：

A new algorithm for the solution of quadratic programming problems is put forward in terms ofthe mixed energy theory and is further used for the incremental solution of elastic-plastic truss structures.Themethod proposed is different from the traditional one,for which the unknown variables are selected just inone class such as displacements or stresses.The present method selects the variables in the mixed form withboth displacement and stress.As the method is established in the hybrid space,the information found in theprevious incremental step can be used for the solution of the present step,making the algorithm highly effi-cient in the numerical solution process of quadratic programming problems.The results obained in the exam-ples of the elastie-plastic solution of the truss structures verify what has been predicted in the theoretical anal-ysis.

英文摘要：

A new algorithm for the solution of quadratic programming problemsis put forward in terms of the mixed energy theory and is furtherused for the incremental solution of elastic-plastic trussstructures. The method proposed is different from the traditionalone, for which the unknown variables are selected just in one classsuch as displacements or stresses. The present method selects thevariables in the mixed form with both displacement and stress. As themethod is established in the hybrid space, the information found inthe previous incremental step can be used for the solution of thepresent step, making the algorithm highly effi- cient in thenumerical solution process of quadratic programming problems. Theresults obtained in the exm- ples of the elastic-plastic solution ofthe truss structures verify what has been predicted in thetheoretical anal- ysis.