Analysis of effective pore pressure in asphalt pavement based on computational fluid dynamics calculation

Abstract

A micromechanical model was established based on the fluid dynamics theory. This model could be used to calculate several kinds of data when the asphalt pavement under the influence of traffic loading is in water-saturated condition. The results showed that the maximum pressure inside the effective pore was located at the junction between exit slits and the pore wall. There was a positive correlation between the pressure and the vehicle speed. Therefore, the repeated traffic loading could cause emulsification, shift and even peeling of the asphalt membrane. Moreover, the bigger size of the exit slit is, the higher velocity of the fluid has. The high velocity flow keeps scouring both the exit slit and the lower boundary of pore wall. It will cause a bigger slit. Pressure distribution inside the effective pore is related to the number of the exit slit which connect with the pore. More exit slits means bigger pressure inside the effective pore. In addition, if asphalt membranes at exit slits have micro-cracking, the cumulative damage could appear easily and asphalt membranes could be peeled easily. Finally, a test was conducted so as to obtain the bonding strength and adhesion strength between asphalt and aggregate. Then, we can get accurate damage form and position during the scour process by comparing the numerical simulation results with experiment results.

Measurement and Evaluation for Interbedded Pore Water Pressure of Saturated Asphalt Pavement under Vehicle Loading

“…Thus, the measurement range of the sensor should be slightly larger than the maximum pore water pressure and not too large. A large number of numerical calculations and theoretical analyses have been carried out to calculate the value of pore water pressure [15][16][17]. For example, the pore water pressure of the pavement layers was calculated in the range of 100 kpa to 500 kpa in 2005 by Luo ZG [18].…”

“…As can be summarized from table, the Abp and time are exponential distributed. The empirical formula of Abp at different speed is described by Equation (17), the coefficients k and b are determined by the speed.…”

Evaluation on Distribution Characteristics of Pore Water Pressure within Saturated Pavement Structure Based on the Proposed Tire-Fluid-Pavement Coupling Model

“…In order to study the change law of pore water pressure in asphalt pavement, studies about numerical calculations and theoretical analyses have been carried out to calculate the pore water pressure [8][9][10][11][12][13]. For example, based on the porous media theory and Biot theory, Sun et al [14] built a hydromechanical coupling model to investigate the spatial distribution and the change law with time of pore water pressure in asphalt pavement.…”

Evolution of dynamic flow behavior in asphalt mixtures exposed to freeze-thaw cycles

“…However, these approaches cannot account for the dynamic moisture transport process, which is ubiquitous in asphalt mixture [21][22][23]. As pointed out by Vardanega [24] and Guo [25], there are still unanswered fundamental questions about moisture in asphalt mixtures, such as "How does wetting front pass through pore structure in asphalt mixtures?" and "How does moisture in asphalt mixtures interact with pore structure in asphalt mixture exposed to environmental load and vehicle load?".…”