Introduction and Use of High Damping Rubber Bearings
At present, the state has classified the pot rubber bearings into 31 levels of bearing capacity, with a bearing capacity of 0.8MN-60MN, which can meet the needs of large-scale bridge construction.
The high damping rubber bearing, also known as HDR bearing, is a product designed in accordance with the national standard GB/T20688 Seismic-protection Isolators Test Methods. It is made by adding various compounding agents to natural rubber to improve the damping performance of rubber (increasing hysteresis loss and reducing its storage modulus), and then made of rubber with a damping effect, similar to the structure of ordinary rubber bearings. This is a laminated product composed of steel plate and rubber through thermal vulcanization.
Generally, it can be divided into fixed bearing, which means that the horizontal bearing capacity in all directions and the non-slip direction of the one-way movable bearing is not less than 10% of the rigid bearing capacity of the bearing. The horizontal bearing capacity of the earthquake-resistant bearing shall not be less than 20% of the rigid bearing capacity of the bearing. The rotation angle of the support is not less than 0.02rad. After lubricating with 5201 silicone grease, the minimum design friction coefficient of the normal temperature movable bearing is 0.03. After adding 5201 silicone grease, the minimum design friction coefficient of the cold-resistant movable bearing is 0.06.
- Trinity of vertical bearing capacity, horizontal restoring force, and damping;
- The hysteretic characteristics of the support (load-deformation curve) are full and energy consumption is significant;
- Improved rubber formula, equivalent damping ratio can reach over 12%;
- Low maintenance and management costs (no need for other damping devices);
- After a major earthquake, the residual deformation is extremely small, and there is no need to replace it;
- The surface of the high-damping rubber bearing is covered with a rubber protective layer to protect the internal rubber from ozone and ultraviolet rays and has better aging resistance, and the equivalent damping ratio in 50 years is reduced by less than 2%;
- HDR high damping rubber has low-temperature dependence and is widely used in different climate areas;
- HDR high damping rubber has superior creep performance like natural rubber;
- Environmental protection and pollution-free.