Viscoelastic high damping rubber material uses the viscoelasticity of rubber itself to damp structural vibration and noise, which can be divided into free damping treatment and constrained damping treatment. The free damping treatment is to stick a layer of damping rubber on the surface of the structure. When the structure vibrates, the viscous internal friction between rubber molecular chains consumes part of the vibration energy, reducing the vibration; Restraint damping treatment is to stick a layer of damping rubber on the surface of the structure, and then stick a layer of constraint plate outside. When the structure vibrates, the damping material is subject to shear action, and part of the vibration energy is converted into heat energy for damping. The high damping isolation rubber bearing is the viscoelastic high damping rubber material. The structural vibration is constrained and damped by the viscoelasticity of the rubber itself to absorb energy and reduce the seismic force; The rubber material also has greater ductility, which can extend the natural vibration period of the structure during the earthquake and avoid the impact of seismic peak load
Sliding support and hinge are different. If the hinge does not transfer the bending moment but the force, the sliding support does not transfer the bending moment and does not transfer the horizontal shear force. 2. It is not ambitious to only make the hinge effect, or it can be completely detached to make the sliding support, or it can be made into the ATc, and it can not be disconnected. 3. The more important resistance of earthquake prevention planning may dissipate earthquake energy, rather than just a certain force or bending moment. Energy is the product of force (generalized force, including bending moment) and displacement (generalized displacement, including rotation angle). Note: The concept must be clear, otherwise many problems will be neglected and potential safety hazards will be left.
***Because of sliding, there is no shear force stairs The impact on the main body is small, which is more consistent with the assumption of stair opening, so that the structure is still a pure structure rather than a diagonal bracing structure.
Secondly, the sliding bearing will not be damaged by horizontal extrusion or tension due to the lack of horizontal force. Third, there is no energy consumption. This is the way to avoid earthquake force. Although there will be displacement at the sliding support, there is no stiffness, so there will be no force effect under sliding. As the primary escape way, who will make the stairs the most easily damaged energy consuming components.
The effect of sliding bearing is not earthquake resistance, but to eliminate the bad influence of the diagonal bracing of the stair plate on the structural column, so that the force model of the original structure is still a pure structure. One is resistance, the other is elimination. In the words of Chen Qinglai, "resistance" is to make trouble with God, and the planning should focus on elimination. Therefore, energy dissipation should also be the general direction of future seismic planning. A section of ATc type stairs is disconnected from the structural column, so the force generated by the stairs cannot be transmitted to the structural column.
The sliding support only needs to be able to make the force of the diagonal bracing of the stairs not transmitted to the main body to go up the stairs, so it is not necessary to participate in all calculations. Compared with the structural structure, the staircase has a relatively large stiffness, and the distributed shear force is large. The earthquake is suitable for damage. The hinge joint does not transfer the bending moment, which greatly reduces the impact of the staircase stiffness on the entire structure. There is displacement at the sliding support, but there is no stiffness, so there is no force effect under sliding.
The sliding support has slipped, so there is no shear force. In the earthquake effect, the stairs have less impact on the main body, which is more consistent with the assumption that the stairs have holes, so the structure is still a pure structure rather than a diagonal bracing structure
