DEVELOPMENT ON NEW 3DFEM ANALYTICAL METHOD AND MANAGEMENT IN PRESTRESSING PROCESS FOR PC STRUCTURES

Abstract

 In this paper, new analytical method to introduce prestress is developed in order to have more precise prediction of friction loss of tendon forces as well as centripetal forces due to arbitrary curved tendon in PC structures with arbitrary 3-dimensional configuration. Using the development of this proposed method, it is possible to calculate the elongation amount at the end of the tendon containing the deformation of concrete, moreover the effect of the anchorage-seating loss can be also rationally calculated. Numerical analyses are performed using the proposed method for overhang erection of actual bridges example of prestressing and PC structures with helical curved surfaces, then the validity of the proposed method and issues in applying the initial strain method to prestressing problems are discussed. Furthermore, based on actual examples of tension management of PC component girders, a prestressing management chart is drawn using the proposed method, and improvements to procedure to draw the conventional prestressing management chart are also examined.