Discuss On Simulate Analysis And Moment Modification In Prestressed Concrete Frame

Recently, the prestressed concrete structures are widely used in the civil engineering field in China. Great developments have been observed for the rules of plastic internal force redistribution and the design method of moment modification both in China and abroad. Nevertheless, the latter is mainly based on the prestressed continuous beams, and a little on prestressed frame. Here, a series of simulations on the prestressed framed are designed and analysed with the bonded post-tensioned partially prestressed frames as research objects. The research indicates the rules of plastic internal force redistribution. Furthermore, moment modification related problems are discussed and appropriate suggestions on the moment modification for prestressed frames are made. All of the above are presented in this thesis.Through the non-linear analysis on the massive simulations for prestressed frame, together with related literature, the following conclusions are made:①The load moment and secondary moment of prestressed frame are more complex than prestressed continuous beams. In the consequence, the rules of plastic internal force redistribution and the design method of moment modification of prestressed frame are different from prestressed continuous beams.②The secondary moment M seccould not be ignored in moment modification of prestressed frames. The influences caused by M secincluding both favorable and unfavorable influences, can be considered in the course of load moment modification.③Through the non-linear analysis on the massive simulations for prestressed frame, the rules of plastic internal force redistribution of prestressed frames are discovered. Among the influencing factors, relative height of equivalent compression zoneξ, secondary moment M secand horizontal load are the main factors. Special attention should be paid for the three factors during the prestressed frames design process.④Based upon the non-linear analysis on the massive simulations for prestressed frame, and referencing the design code for moment modification to prestressed hyperstatic structures in China and abroad, appropriate suggestions for moment modification of prestressed frames are made and discussed in this paper.⑤Base on the suggestions of the moment modification, three-storey-double-span prestressed frames are designed and the non-linear analysis is carried out here. On the evaluation of prestressed frames under normal load state and ultimate load state, the suggestions for moment modification of prestressed frames are proved to be reasonable and securable.