The durability of seismic isolation bearings is a important factor to ensure safety and performance of buildings. The following are several key points regarding the durability of seismic isolation bearings:
1. Service life of seismic isolation LRB:
According to the standards of the construction industry in the People's Republic of China, building isolation rubber bearings should have a service life of not less than 60 years. This means that under normal use and maintenance, seismic isolation bearings should be able to maintain their effective function for at least 60 years.
2. Durability issue of LRB:
The durability of seismic isolation rubber bearings depends on the rubber material quality and receipt, and is mainly affected by oxidation reactions and creep. To improve durability, antioxidants can be added to rubber and durable rubber can be used as a protective layer. At present, the service life of our factory produced seismic isolation rubber bearings of LRB is equivalent to the buildings.
3. Anti aging performance of seismic rubber bearings:
The aging performance bridge rubber bearing is a very important performance and it is also an important testing item when doing the testing of rubber materials, normally, it is a important factor to tell weather the rubber bearing is good quality.
The aging of rubber isolation bearings is the result of long-term comprehensive effects of external environment. Short term artificial environmental testing in the laboratory can only serve as a basis for assessing durability.
The actual engineering application situation and on-site investigation are the key to drawing the most authentic and reliable conclusions. For example, the railway bridge bearings in Melbourne, Australia have been using rubber pads made of natural rubber for over 100 years. The aging test results show that, except for the formation of an aging "hard shell" on the surface layer, there is no aging phenomenon in the internal rubber material, and there is no change in performance.
Although the aging of rubber material is so important, we need to Taking into account other parameters such as tensile strength, hardness, elongation at break, etc, to make sure the bridge rubber bearings have good shearing capacity too.
4. Maintenance and inspection:
When LRB are used on bridge or building constructions. The Maintenance and inspection of seismic isolated buildings are important, it measures to ensure the durability of seismic isolation bearings. Inspections include routine checks, regular checks, and emergency checks.
Routine inspections should be conducted once a year, and regular inspections should be conducted in the third, fifth, and tenth years after completion, followed by every ten years thereafter.
After earthquakes or fires may cause damage to components and equipment related to the isolation layer, emergency inspections should be carried out in a timely manner. So we can know that Maintenance and inspection of seismic isolated buildings are important measures to ensure the durability of seismic isolation bearings.
Emergency inspection: In the event of earthquakes or fires that may cause damage to the components and devices related to the isolation layer, emergency inspections should be conducted in a timely manner.
5. Environmental requirements for seismic isolation bearing:
The building friction pendulum seismic isolation bearings are not very resistant to moisture. The seismic isolation layer should be kept dry and there should be no water accumulation or liquid leakage. The building friction pendulum seismic isolation bearings should not be immersed in water to avoid metal materials (especially non stainless steel parts) rusting, pollution, and even damage to the friction surface.
Maintenance of metal parts: All exposed metal parts are coated with heavy-duty coatings, but in order to prevent rust or corrosion, it is inevitable that the paint protection layer of the seismic isolation support will be damaged to some extent during construction, installation, and use. Continuous maintenance should be carried out to keep the seismic isolation bearing in good condition.
6. Materials and performance of seismic isolation bearing :
The materials and performance of seismic isolation bearings directly affect the LRB service life. For example, seismic isolation bearings made of rubber materials, like lead rubber bearing, high damping rubber bearing,they have the characteristics of high damping, lightweight, good flexibility, resistance to high and low temperature effects, and aging resistance, making them suitable for special working conditions such as high temperature, low temperature, and corrosive environments.
In summary, the durability of seismic isolation bearings is influenced by various factors, including material selection, environmental conditions, aging issues, and regular maintenance and inspection. Through reasonable design, high-quality material selection, and regular maintenance and inspection, the durability of seismic isolation bearings can be ensured, thereby ensuring the safety and performance of buildings
