CRYOGENIC TESTING PER EAD 160004‑00‑0301 (Section C.2.2)
In 2023, we began conducting cryogenic tests according to Section C.2.2 of the European Assessment Document EAD 160004‑00‑0301 "Post-Tensioning Kits for Prestressing of Structures" which superseded the European Organisation for Technical Approvals (EOTA) Document ETAG 013. "Guideline for European Technical Approval of Post-Tensioning Kits for Prestressing of Structures" (These are commonly called Post-Tensioning Systems).
We designed and custom-built the extended-length grips using stainless steel and high-strength aluminum to apply uniform loading while the strand and grips are completely submerged in liquid nitrogen for over one hour before loading to failure. These special grips allow the tensile failures to occcur away from the gripping location and the determination of the true cryogenic tensile strength of the strand. Loading is applied using an MTS servo-controlled hydraulic actuator.
