On May 13th, 2023, China Railway Equipment Company and ONTON held a Jambo construction prestressed test on R25 self drilling hollow bar at Zijia Tunnel project on the Yaonan Expressway. Two tests were conducted:
R25 prestressed hollow anchor bar with expansion shell
R25 anchor bar prestress requirement is >60kN, we tested it at 1.2 times (72kN), the test results: head pulling force >100kN, prestress >72kN;
R25 prestressed hollow anchor bar with resin
R25 anchor bar prestress requirement is >60kN, we tested it at 1.2 times (72kN).
The test results: head pulling force >78kN at 1 minute and >200kN at 5 minutes after resin mixing and gelation, prestress >72kN.The total demand for anchor rods in this project is more than 200,000 meters. As of this month, ONTON has provided more than 130,000 meters of R25 anchor rods to Yaonan Expressway. All the anchor rods will be supplied within two years.
