The Post-Tensioning Institute (PTI) Bonded Tendon Committee M-50 and American Segmental Bridge Institute (ASBI) joint task group collaborated on the new PTI/ASBI M50. 3-12, Guide Specification for Grouted Post-Tensioning, that specifies materials, installation, stressing and corrosion protection levels for grouted post-tensioning systems.
“The goal is to have the specification adopted by most State Departments of Transportation (DOTs),” explained PTI Technical Director, Miroslav Vejvoda, “which will simplify the approval process for the systems used in different areas of the country while allowing for consideration of local environmental conditions.” Qualification requirements for field personnel are also outlined in the specification to emphasize that the knowledge and experience of all involved in the construction process contribute to the long-term durability of the structure.
Earlier in 2012, PTI published significant updates to two other bonded (grouted) post-tensioning documents. The PTI M55.1-12, Specification for Grouting of Post-Tensioned Structures provides requirements for the selection, design and installation of cementitious grouts and ducts for post-tensioning systems used in bridges, containment structures and buildings. The 2012 edition includes updates in chloride testing, inclined tube testing, material certification requirements, prohibition of tendon flushing, pumping pressure and personnel qualification.
Updates and additions to thePTI DC45.1-12, Recommendations for Stay Cable Design, Testing and Installation, include several significant additions and updates, such as the strength resistance factors including extrados stay systems, fire resistance qualification testing details and cable loss due to fire provisions, wind loads and cable galloping provisions, fatigue and static strength testing requirements, HDPE pipe requirements, and some other updates.
The Post-Tensioning Institute also offers the Level 1&2 Bonded PT Field Specialist certification workshop that includes the publication updates in its new course material and field demonstrations. To learn more about bonded post-tensioning, order publications in digital or hardcopy format, or sign up for a certification workshop, visit www.post-tensioning.org.