Knowledge of the temperature sensitivity of foamed asphalt stiffness is very important in mix and structural design, field non-destructive testing and advanced research. However, this subject has not been studied extensively, especially the effects of the stress state on the temperature sensitivity, which is essential to understand the behavior of weakly bonded granular materials. This paper first presents triaxial resilient modulus testing results of foamed asphalt treated materials with various asphalt contents at various temperatures. General observations are made in terms of the effects of the bulk stress, deviator stress, temperature and their interactions. Based on these observations, the temperature sensitivity coefficient of foamed asphalt stiffness is defined and a simplified model to predict foamed asphalt mix stiffness at any triaxial stress state and temperature is proposed and validated. A procedure to normalize back-calculated resilient modulus to a standard temperature is also presented. The essential step of this procedure is to estimate the temperature sensitivity coefficient based on the field test results at various temperatures. Finally, an example is presented comparing the stiffness of a foamed asphalt material over two years. It was found that the stiffness did not change significantly over the two years period, despite the accumulation of traffic loading.
[2]
W. Heukelom.
OBSERVATIONS ON THE RHEOLOGY AND FRACTURE OF BITUMENS AND ASPHALT MIXES
,
1966
.
[3]
Mofreh Saleh.
Effect of Aggregate Gradation, Mineral Fillers, Bitumen Grade, and Source on Mechanical Properties of Foamed Bitumen-Stabilized Mixes
,
2006
.
[4]
S Baltzer,et al.
PREDICTION OF AC MAT TEMPERATURES FOR ROUTINE LOAD/DEFLECTION MEASUREMENTS
,
1994
.
[5]
C Overby,et al.
BITUMEN FOAMING: AN INNOVATIVE TECHNIQUE USED ON A LARGE SCALE FOR PAVEMENT REHABILITATION IN AFRICA
,
2000
.
[6]
Kim Jonathan Jenkins,et al.
Mix design considerations for cold and half-warm bituminous mixes with emphasis of foamed bitumen
,
2000
.
[7]
Murad Y. Abu-Farsakh,et al.
Louisiana Experience with Foamed Recycled Asphalt Pavement Base Materials
,
2003
.
[8]
Natalie Andrews.
Foamed Bitumen Mix: Soil or Asphalt?
,
2002
.
[9]
W Heuckelom,et al.
AN IMPROVED METHOD OF CHARACTERIZING ASPHALTIC BITUMENS WITH THE AIR OF THEIR MECHANICAL PROPERTIES
,
1973
.