THREE-DIMENSIONAL FINITE ELEMENT MODELING OF PERVIOUS CONCRETE PAVEMENT: VERTICAL POROSITY DISTRIBUTION APPROACH

Pervious concrete has the unique characteristic of allowing water to pass through its porous matrix. . Pervious concrete pavement systems usually have three main layers, pervious co ncrete on the top, a subbase layer of aggregate for water storage in the middle and the subgrade (soil) layer below. Finite element mod eling of this novel material is challenging due to its complex porous characteristics. In this paper, a method has been p roposed to model pervious concrete pavement using f inite element methods, which includes a modified approach to capture the unique vertical porosity distribution in the pervious conc rete layer by averaging the distribution in three distinct vertical sections. The mechanical properties of the pervious concrete l ayer are assumed to vary along its depth since the porosity of the pervious concrete a lso varies with depth. ABAQUS, a general-purpose fi nite element software package was used to develop the model and perform the analy sis. The model was validated through a convergence study, and in comparison with the analytical theory of tensile stress and de flection for traditional concrete pavement. In addi tion, the significance of the porosity distribution model was validated by compar ing the results from EverFE ‐ a specific software f or pavement structure analysis. It was found that there is significant difference itensile stress if modeled using the modified vert ical porosity distribution in the previous concrete layer to more fully capture its v ertical porosity distribution, as compared to an av eraged porosity model in the previous concrete layer. It was also noted that com pressive stress demand may have increased importanc e for pervious concrete, but only for highly porous applications which are not cused.