## 5 Conclusions and Future Work  
In this paper, a PC beam-column connection incorporating pretensioned debonded partial tendons is introduced. To more accurately evaluate the performance of this connection at the flexural ultimate limit, an analytical model is adopted to reflect the deformation compatibility and force equilibrium conditions of the PC beam and column members, as well as the unbonded tendon in a precise manner. Based on this, iterative and direct methods for evaluating the ultimate performance of the beam are proposed. The proposed method is verified by cyclic loading test on the beam-column subassemblages. The main conclusions can be summarized as follows. Figure 16: Evaluation accuracy of \(\Delta_{c,ex}\) and \(R_{b,u}\) by simplified method before and after correction: (a) \(\mathrm{D}_{c,ex}\); (b) \(R_{b,u}\). Figure 15: Evaluation accuracy of \(P_{b,u}\) by simplified method without correction. The analytical model can more comprehensively and accurately consider the stress-strain distribution of concrete and tendons at each section of the PC beam, and also consider the unequal tensile forces of multiple partial tendons. However, the existing methods cannot evaluate the ultimate deformation of the connection or give the exact tendon strain at the ultimate state. Some other methods can only consider equal axial forces of multiple tendons or cannot be applied in the case of the partial tendons. Therefore, the proposed analytical model and methods are superior to most existing ones. 2. The proposed evaluation method can reasonably evaluate the ultimate bending moment at the beam end, the corresponding beam deflection and the tendon strains with good accuracy. The evaluation errors for the ultimate bending moment were within 10%, and for the beam deflection angle the errors were almost less than 20%. With respect to the tendon strains, regardless of the tendon positions, the evaluation errors were within 15%. The good evaluation accuracy indicates the proposed analytical model can reflect the behavior of the PC beam-column connection properly. 3. The iterative method using the iterative process is proposed, and then simplified to the direct method, which does not require the iterative calculation process, by means of the approximation of axial concrete shortening at the beam-column interface. The simplified method can give evaluations of similar accuracy as the iterative one by introducing the correction factor, which is therefore more suitable for engineering design. 4. The self-centering and low-damage characteristics of the proposed PC connection are confirmed by cyclic loading tests. Through the comprehensive evaluation of the ultimate performance of the connection, the self-centering and low-damage characteristics could be guaranteed in strong earthquake by preventing concrete spalling or tendons yielding, while the bearing and deformation capacity of the connection could be fully utilized. By applying the analytical model and design method proposed in this paper, the performance at other limit states of the debonded PC connection could be further evaluated, so that the entire deformation-restoring force relationship of the connection could be obtained. On this basis, design parameters such as sectional area, length, and prestressing level of the debonded partial tendons could be optimized. In addition, by using the deformation-restoring force relationship, the semiplastic hinges in the frame structures created by the debonded PC connection are simulated. Based on this, further research could be conducted on seismic performance of the frames. Such a debonded PC frame has self-centering and low-damage characteristics and thus exhibits superior resilience under strong earthquakes. Using dampers to enhance the energy dissipation and control the seismic response will further improve the structural performance. These issues will be considered in following studies. Conceptualization, K.J., L.H. and K.K. ; Methodology, K.J. and R.O. ; Investigation, K.J., L.H. and R.O. ; Writing--original draft, K.J.