ABSTRACT
A summary of the details of three pavements that rutted early in their lives is given in Table 1.
Each pavement was on the State Highway network and constructed to the TNZ B/2 specification. The basecourse materials all complied with the TNZ M/4 specification which specifies a 40 mm maximum particle size, low to zero plasticity, and at least 70% broken faces in the coarse aggregate. The sub-base materials were all a 65 mm maximum particle size, and partly to fully crushed. The construction specification TNZ B/2 specifies a compaction level in terms of percentage of MDD. MDD is determined in the laboratory using a vibratory hammer compaction method. The
New Zealand method is similar to the EU/BS method. The compaction requirements are given inTable 2.The necessity to achieve 95% of MDD compaction was established in a previous project.
