A Friction Damper for Post-Tensioned Precast Concrete Moment Frames

摘要

style="text-align: left;">This paper describes the development of a new type of friction damper for unbonded post-tensioned precast concrete building moment frame structures in seismic regions. Previous research has shown  that these structures have desirable seismic characteristics such as a self-centering capability and an ability to undergo large nonlinear lateral displacements with little damage; however, displacements   during an earthquake may be larger than acceptable. To reduce displacements, the proposed friction dampers are placed at selected beam-column joints, and dissipation of energy occurs through joint gap opening.  Large scale beam-column subassemblies with and without dampers were tested under reversed cyclic loading. Results show that the dampers can provide a significant amount of supplemental energy  dissipation at the beam ends, while the self-centering capability of the structure is preserved.  >References style="text-align: left;">1. Priestley, M., and Tao, J., href=" http://dx.doi.org/10.15554/pcij.01011993.58.69 " title="a€?Seismic Response of Precast Prestressed Concrete Frames with Partially Debonded Tendons,a€?" target="_blank">a€?Seismic Response of Precast Prestressed Concrete Frames with Partially Debonded Tendons,a€? PCI JOURNAL, V. 38, No. 1, January-February 1993, pp. 58-69. style="text-align: left;">2. ACT Committee 318, a€?Building Code Requirements for Structural Concrete (ACT 318-02) and Commentary (318R-02),a€? American Concrete Institute, Farmington Hills, MI, 1999. style="text-align: left;">3. ACI Innovation Task Group 1, a€?Acceptance Criteria for Moment Frames Based on Structural Testing (T1.1-01) and Commentary (T1.1 R-0 1),a€? American Concrete Institute, Farmington Hills, MI,  2001, 11 pp. style="text-align: left;">4. Englekirk, R., href="http://dx.doi.org/10.15554/pcij.07012002.56.71 " title="a€?Design-Construction of The Paramount - A 39-Story Precast Prestressed Concrete Apartment Building,a€?" target="_blank">a€?Design-Construction of The Paramount - A 39-Story Precast Prestressed Concrete Apartment Building,a€? PCI JOURNAL, V. 47, No. 4, July-August 2002, pp. 56-71. style="text-align: left;">5. Stanton, J., and Nakalci, S., a€?Design Guidelines for Precast Concrete Seismic Structural Systemsa€?, Report No. PRESSS 01/03-09, Department of Civil Engineering, University of Washington, Seattle,  WA, February 2002. style="text-align: left;">6. ACI Innovation Task Group 1, a€?Special Hybrid Moment Frames Composed of Discretely Jointed Precast and Post-Tensioned Concrete Members (ACT Ti .2-XX) and Commentary (T1.2R-XX),a€? ACI  Structural Journal, V. 98, No. 5, September-October 2001, pp. 771-784. style="text-align: left;">7. El-Sheikh, M., Sause, R., Pessiki, S., and Lu, L.W., href="http://dx.doi.org/10.14359/841 " title="a€?Moment Rotation Behavior of Unbonded Post-Tensioned Precast Concrete Beam-Column Connections,a€? " target="_blank">a€?Moment Rotation Behavior of Unbonded Post-Tensioned Precast Concrete Beam-Column Connections,a€? ACI Structural Journal, V. 97, No. 1,  January-February 2000, pp. 122-131. style="text-align: left;">8. Priestley, M., Sritharan, S., Conley, J., and Pampanin, S., href=" http://dx.doi.org/10.15554/pcij.11011999.42.67 " title="a€?Preliminary Results and Conclusions from the PRESSS Five-Story Precast Concrete Test Building,a€?" target="_blank">a€?Preliminary Results and Conclusions from the PRESSS Five-Story Precast Concrete Test Building,a€? PCI JOURNAL, V. 44, No. 6,  November-December 1999, pp. 42-67. style="text-align: left;">9. El-Sheikh, M., Sause, R., Pessiki, S., and Lu, L.W., href=" http://dx.doi.org/10.15554/pcij.05011999.54.71 " title="a€?Seismic Behavior and Design of Unbonded Post-Tensioned Precast Concrete Frames,a€? " target="_blank">a€?Seismic Behavior and Design of Unbonded Post-