Corrosion protection method and performance for prestressing strands
In-Seok Yoon 1, Thomas H.-K. Kang 2, Hyeongyeop Shin 2
1 Construction Info. Eng., Induk University, Republic of Korea
2 Architecture and Architectural Engineering, Seoul National University, Republic of Korea
In this study, the performance of corrosion protection systems used in post-tensioning construction fields is discussed. First, a literature review of prior research on stress corrosion is conducted, followed by in-depth review of corrosion protection methods applied in the field of post-tensioning construction, and finally performance of single strand specimens having bonded (grouted) strand, unbonded (greased) strand, and greased sheathed strand (GSS) with and without grouting is experimentally investigated using electrochemical and weight loss measurement in accordance with modifications based on PTI M55.1-12 specification. Corrosion was activated by: chloride ion (Cl-), and chloride ion and dissolved oxygen (Cl- + DO). Results indicated that all specimens using HDPE (high-density polyethylene) sheath showed excellent corrosion protection performance.
Key words: Corrosion protective system, chloride, dissolved oxygen, HDPE, grease, cement grout