IDEAL CT, RT and High Temp IDT

The concept of Balanced Mix Design (BMD) originated when lean mixtures, developed using Hamburg Wheel Tracker limits, began to exhibit premature cracking. This spurred attempts to mitigate a shift from rut-resistant mixtures prone to cracking to crack-resistant mixtures prone to rutting by introducing a balanced approach involving two tests to address these failure mechanisms. Given the lengthy duration of fatigue tests, some researchers applied fracture mechanic analysis to simple, cost-effective, preexisting monotonic tests, striving to devise a more practical method for assessing resistance to cracking.

In Texas, the Hamburg and Overlay tests are employed for balanced mix design, and it is anticipated that IDEAL CT and RT will serve as a complementary quick screening tests.

Humboldt manufactures the 5125A, a superior machine capable of conducting existing and future monotonic tests. At present, it can be used to run the following tests along with R value/Hveem.

• IDEAL-CT (TTI Method) — ASTM D8225

• I-FIT (SCB IL Method) — AASHTO TP124

• SCB (LSU Method) — ASTM D8044

• IDEAL-RT (TTI Method) — ASTM D8360-22

• ISS (Interlayer Shear Strength) — AASHTO TP114

• TSR — AASHTO T283

• Marshall — ASTM D6927, AASHTO T245

https://theasphaltpro.com/articles/comparing-ctindex-devices