###### Abstract
Previous researchers have also applied similar connections with debonded tendons to other types of structural components, including concrete rocking walls [29, 30, 31, 32, 33, 34], coupling beams between shear walls [35, 36], rocking steel braced frames [37, 38, 39, 40], beam-column connections in steel moment frames [41, 42, 43, 44], rocking cross-laminated timber (CLT) panels [45, 46], laminated veneer lumber (LVL) panels [47, 48], and masonry walls [49, 50]. All of these structural components were found to exhibit superior self-centering and low damage characteristics from the experimental studies. The seismic performance of the debonded PC frames is dominated by the beam-column connections, and the frames are generally designed as strong column-weak beam systems to achieve ductile seismic behavior. Hence, an appropriate assessment of the load-bearing capacity and deformation of the debonded PC beam at the performance limit is essential for the correct simulation of the seismic response and reliable performance-based seismic design. One of the earliest studies on the ultimate flexural strength and deformation of debonded poststenioned beams was carried out by [PERSON] and [PERSON] [51], where concentrated vertical loads were considered. Regarding the debonded beam-column connection subassemblages shown in Figure 1, some existing methods [52, 53] can directly calculate the ultimate flexural capacity at the beam ends when the strain at the extreme concrete fiber reaches the ultimate limit, but they cannot evaluate the corresponding beam deflection. Some other methods can evaluate the ultimate flexural capacity and deformation [54, 55, 17, 56], but based on determined stresses and strains of the debonded tendons. Since the tendons remain elastic as a precondition for the connections to have the  
Figure 1: Test result of PC beam–column connection subassemblage: (**a**) damage map after loading to 2.0% of drift angle; (**b**) load–deformation diagram. self-centering capacity, it is necessary to accurately evaluate the strain of the tendons at the ultimate flexural state. In numerous previous studies [16; 18; 20; 23; 24], the tendons were designed to pass through the entire PC beams and even multiple spans of the entire frame. This arrangement allows the tensile stresses generated by the tendons to be distributed over a long range, thus ensuring that the tensile stresses do not exceed the yield limit, even when the tensile forces acting on the tendons are significant. However, when the size of structures becomes large, this through-length arrangement of tendons requires a high level of tensioning work to achieve the designed prestress level. In this paper, therefore, a PC beam-column connection with debonded partial tendons is introduced, and the direct evaluation methods for the ultimate flexural strength and deflection of the beam are developed. This method takes into account the different tensile forces of multiple debonded tendons, which cannot be considered by the existing methods [17; 54; 55; 57; 58]. In this work, the analytical model of the PC connections and the performance evaluation methods for the ultimate flexural limit are developed. Firstly, the relationships between the deformation and strain of concrete and tendons in each section of the beam are established based on the deformation compatibility and force equilibrium conditions. The analytical model considers the beam deformation developed in the prestressed concrete part and the reinforced concrete part. This analytical model is precise enough to facilitate a comprehensive evaluation of strength and deformation of the beam, as well as the strains of the debonded partial tendons, at the ultimate flexural limit. The accuracy of the evaluation method is verified by cyclic loading tests of the beam-column connection subassemblages.