德克斯达集团|可靠的连接

DEXTRA
领英 Facebook YouTube
DEXTRA
领英 Facebook YouTube
我的右旋糖酐

高温下的耦合器性能测试

伦敦帝国理工学院在高温下测试了 Dextra Bartec/Fortec 和 Griptec 耦合器，以评估这些耦合器在发生火灾时的性能。

测试的亮点包括：

  • 研究结果表明，当前的编纂规则可用于评估非拼接钢筋和与 Bartec/Fortec 或 Griptec 连接器连接的钢筋的强度和刚度特性。
  • 在低于 400°C 的温度下，Bartec/Fortec 和 Griptec 接头以及未接头钢筋的极限抗拉强度和刚度不会受到显著影响。
  • 当在低于 500°C 的温度下进行拉伸试验时，Bartec/Fortec 或 Griptec 耦合器区域之外的钢筋仍然普遍会发生故障。

    • 请阅读下面的全文：

    Dextra Bartec/Fortec and Griptec rebar couplers at elevated temperatures

    Dextra have recently collaborated with Imperial College London to investigate the performance of rebar couplers at elevated temperatures, simulating temperatures which could occur in rebar due to fire, both before and after concrete spalling.

    Standard 16mm and 20mm Bartec/Fortec and Griptec couplers were used, as well as non-spliced reinforcement and tests conducted at ambient, elevated steady state and transient elevated temperatures.

    testing machine

    schematic representation of the testing arrangement

    a) testing machine, b) schematic representation of the testing arrangement

    Codified procedures for the fire design of reinforced concrete structures typically give prescriptive recommendations for rebar/coupler cover with the aim of protecting the reinforcement from reaching temperatures above a critical value of around 500°C.

    The test results show that:

  • For both spliced and un-spliced specimens there is a gradual decrease in yield strength as temperature increases.
  • At temperatures below 400°C the ultimate tensile strength and stiffness of the spliced and un-spliced specimens is not significantly affected.
  • When tensile tested at temperatures below 500°C, failure still generally occurred in the rebar outside of the coupler region.

    • The findings also indicate that current codified rules can be used for assessing the strength and stiffness properties of both non-spliced rebar and rebar connected with Bartec/Fortec or Griptec couplers.

    However, the code assumptions regarding the ultimate strain characteristics at elevated temperatures were found to be unrealistic for hot rolled rebar, as well as rebar connected by couplers.

    需要有关我们耦合器的更多信息？

    了解我们的耦合器系列

    参考

    Bompa, D. V., & Elghazouli, A. Y. (2019). Elevated temperature characteristics of steel reinforcement incorporating threaded mechanical couplers. Fire Safety Journal, 104, 8–21. https://doi.org/10.1016/j.firesaf.2018.12.006