Application Of Friction Damper In Vertical Joint Of Prefabricated Shear Wall

The new type of assembled energy-dissipating vertical joint shear wall adopts the implementation method of "strong horizontal joint and weak vertical joint",that is,adopting wet connection such as steel sleeve or slurry-anchor lapping,to form a "strong horizontal joint" for the assembled shear wall,and using friction damper or soft steel damper to form a "weak vertical joint" to make the whole knot.A semi dry structure is formed.Under the excitation of external forces,the vertical joints consume energy before the structure in order to protect the safety of the main body and save the cost of postearthquake repair.Therefore,the study of dampers installed at the vertical joints is very important.A friction damper suitable for vertical joints of assembled shear walls is designed.The damper is very convenient for construction,installation and replacement of parts after earthquake.In order to study the energy dissipation performance of the damper,four kinds of friction materials,rubber,aluminium alloy,brass and carbon fiber,were designed,and low-cycle reciprocating loading was carried out under different pre-tightening forces and displacements under each friction material to explore the effects of friction materials,hysteretic curve of pre-tightening friction damper and energy dissipation stability,and polytetrafluoroethylene gasket was placed at the high-strength bolt.The friction between high strength bolt and steel plate was studied.The test results show that the bolt and friction surface participate in the energy dissipation of the damper together.The energy dissipation of the bolt is more advantageous to the practical application of the damper.The high-strength bolt of the rubber friction material damper is easy to loosen,and the sliding friction force is not as stable as that of the aluminum alloy,brass and carbon fiber dampers.Pre-tightening force and sliding displacement of high-strength bolts have influence on the magnitude of friction force.Comparing the energy dissipation stability,energy dissipation capacity,durability and economy,the aluminum alloy friction damper is most suitable for the vertical joints of the assembled shear wall.Figure 42;Table 10;Reference 58.