02/04/2026
Last week, at Earthquake Engineering Research & Test Center of Guangzhou University, we have subjected one large sliding spherical isolator type HP2 8700/1960 designed by HIRUN and produced, by our qualified production network, using HIRUN INTERNATIONAL sliding material.
The performances requested during the tests of the isolator were:
• Seismic load Nsd 8700 kN
• Seismic displacement DM ± 650 mm
• Maximum displacement capacity DTM ± 980 mm
• Maximum seismic load Nedmax 28234 kN
• Peak velocity 880 mm/s
During the tests the temperatures of the stainless steel, in different positions of both the sliding surfaces, were measured and recorded.
The scope of the test campaign was to put in evidence the very high performance demanding of the recent seismic design in terms of performance stability and extreme resistance to working conditions that includes maximum seismic load several times more the seismic load where the friction performances are verified.
The testing protocol, performed on the same isolator, was including the sequence requested by the TBDY 2018 and most of Turkish project Specification, identified as “horizontal characteristics under cyclic deformation” repeated five times with five different level of vertical load, reaching the maximum value higher than 28000 kN corresponding to an average pressure of 195 MPa and maximum pressure considering EN 1337-2, Reduced area for sliding elements lambda factor is equal to 233 MPa. Considering that HIRUN HIM sliding material, used in the friction pendulum has a proven characteristic compression resistance equal to 300 MPa, the value of 230 MPa is even higher than the maximum design pressure of 300/1.4= 214 MPa.
During the tests the temperature recorded, as also shown in the video, reached the exceptional value of 100⁰C proving the higher Energy Dissipated during the cycles and the extreme resistance of HIRUN INTERNATIONAL sliding material.
The checks performed on the whole isolator, including the sliding material and sliding surfaces, confirmed the HIRUN INTERNATIONAL solutions as perfectly suitable to the highest demanding performances showing the sliding material, in particular, without any appreciable deformation.
Official test report issued by the Earthquake Engineering Research & Test Center of Guangzhou University will be shortly available