DYWIDAG Circular Structure Repair with Hoop Tendons - Comparison of Corrosion Inhibitors for PCCP Tendons
The table below compares corrosion inhibitor used by DSI in its Hoop Tendons for PCCP repair vs. the standards of the Post-Tensioning Institute for unbonded tendons, Ref. Table 3.2.1, of the Post Tensioning Manual, Fifth Ed. This table shows the superior quality of the PCCP tendon inhibitor, in particular, for the specific gravity, dropping point, base no., salt fog, soak tests, and water soluble ions.
| Properties (typical) | Test Method | PCCP Corrosion Inhibitor | PTI Specifications |
|---|---|---|---|
| Specific Gravity @ 77ºF | - | 1.04 | - |
| Density lbs./gal. | - | 8.7 | - |
| Cone Penetration @ 77ºF dmm | ASTM D-217 | 330 | - |
| Dropping Point ºF min. | ASTM D-566 | 500 | 300 |
| Flash Point ºF min. | ASTM D-92 | 345 | 300 |
| Viscosity @ 210ºF cps | - | Thixotropic | - |
| Total Base No. Mg KOH/gm | ASTM D-974 Modified | 190 | - |
| Copper Corrosion Test | ASTM D-130 | 1a | - |
| Rust Preventive Properties of Grease | ASTM D-1743 | 1,1,1 | - |
| Salt Fog @ 100ºF hrs. @ 5 mils Accelerated Corrosion Test | ASTM B-117 | 1500 | 1000 |
| Soak Test: Salt Fog 50/50 Immersion, hrs. | ASTM B-117 Modified | 1000 | 720 |
| Oil Separation @ 160ºF, max. | FTMS 791B Method 321.2 | 0.5 | 0.5 |
| Water %, max. | ASTM D-95 | 0.1 | 0.1 |
| Water Soluble Ions, ppm max. Chlorides Sulfides Nitrates | ASTM D-512 APHA 45002 ASTM D-992-78 | 2 2 4 | 10 10 10 |
| Cubic Thermal Exp. Sheathing Compatibility Hardness % max. Change Volume % max. Change Tensile Strength % max. Change | - ASTM D-4289 ASTM D-4289 ASTM D-638 | 0.0005 10 7 21 | - 15 10 - |
| Application Temp. º F | - | >0 No melt | - |