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Feedback : AAPT - Annual meeting & technical sessions. 18 to 21 March 2001, Clearwater Beach, Florida,USA. Renaldo Lorio UWP Engineers. Location. The venue. Introduction. 344 delegates (44 foreigners, 2 from South Africa).
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Feedback : AAPT - Annual meeting & technical sessions 18 to 21 March 2001, Clearwater Beach, Florida,USA Renaldo Lorio UWP Engineers
Introduction • 344 delegates (44 foreigners, 2 from South Africa). • 24 Papers - 60% by research / academia and 40 % from practice (majority of papers to a certain extent related to Superpave).
Attendance 27% 25% 17% 15% 13% 2%
Structure of the meeting • Annual business meeting • Government Engineers Forum (GEF) • Four technical sessions • One symposium • Annual banquet All the sessions were in series (no parallel or breakaway sessions)
Government Engineers Forum • New format (participation of all delegates) • Two topics : • Density measurements and QC/QA • Joint construction (especially long. joints)
Technical session I This session focused primarily on volumetric considerations (esp. VMA) • Current Superpave specifications too limiting (coarse graded mixtures with lower than required VMA often unnecessary penalized). (Anderson et al.) • VMA should not be a fixed value but should be determined for each type of aggregate. (Coree et al.)
Technical session II Various topics in this session • Internal structure of asphalt samples compacted with SGC – different from field samples, this affects performance testing. (Tashman et al.) • VDOT’s PG binder database – user and producer benefits. (Haddock et al.) • Pavement failures due to stripping - no surprise here. Keep the water out of the pavement. !! (Kandhal et al.)
Technical session III Session devoted to bituminous binders (Bahia et al.) • G*/sind for rutting and G*sind for fatigue are not appropriate performance parameters - propose Jv and Np (DSR measurements).
Technical session IV Various topics in this session • MMLS3 – development of criteria for rutting evaluation at WesTrack. (Epps et al.) • New fundamental material model to describe fatigue cracking (fracture mechanics). (Roque et al.)
Symposium • Some contractors are not in favour of PRS but prefer performance guarantees • Case study – 7% premium (additional expenditure on installation of subs. drains,smoother paving, extra compaction effort, more personnel for process control).
Closing remarks • Superpave design system still being refined, still a way to go. • Remember to do the basics correctly (Kandhal’s message).