On the Combined Effect of Moisture Diffusion & Cyclic Pore Pressure Generation in AC

Aikaterini Varveri, Sandra Erkens & Tom Scarpas Pavement Engineering, Delft University of Technology

Stavros Avgerinopoulos Faculty of Engineering, De Montfort University

CROW Infradagen 2014, The Netherlands, June 18-19, 2014

Moisture damage in AC

Moisture diffusion

Advective transport

Wheel loading

Pumping action

CO

UP

LIN

G Degradation of the cohesive strength

of the asphalt binder

Loss of the adhesion bond between aggregate & asphalt binder

Long- and short- term processes

Moisture diffusion

Pumping action

Moisture Induced Sensitivity Tester (MIST)

Moisture conditioning protocol

Determination of bath conditioning time

Dt

Fick’s law

Determination of MIST cycles

Samples preparation

Aggregate Type

Bitumen Type

Pen 70/100

Moderately Polymer Modified

(Pen 50/80)

Highly Polymer Modified

(Pen 65/105)

Sandstone SP SM SH

Granite GP GM GH

Tensile Strength Ratio (TSR)

Long- and short-term contribution

Tensile strength degradation

SH

SP

SM

GH

GM

GP

Long- and short-term contribution

Conclusions

Specifically mixtures produced with: - Sandstone aggregates show better moisture damage performance compared to granite mixtures. - polymer modified binders show lower susceptibility to moisture damage compared to those using conventional binders. - Softer bitumen types demonstrate higher moisture damage sensitivity.

The protocol enables: - The evaluation of the moisture resistance of asphalt mixtures and distinguishing mixtures with different moisture damage susceptibility. - The quantification of the individual short- and long-term moisture damage contribution to the overall specimen damage.

Aikaterini Varveri, Sandra Erkens & Tom Scarpas Pavement Engineering, Delft University of Technology

Stavros Avgerinopoulos Faculty of Engineering, De Montfort University

CROW Infradagen 2014, The Netherlands, June 18-19, 2014

Thank you for your attention!