Multi-scale In Situ Investigation of Infiltration Parameter in Pervious Concrete Pavements

Embedded infiltration rings have been historically used to estimate the infiltration properties of pervious concrete (PC) pavements. However, no methodical study has evaluated the effect of the size of embedded rings on the infiltration characteristics of these special pavement systems. The objective of this research was to assess the infiltration rate of PC using a multi-scale, in situ approach through embedding rings of various sizes in pavement slabs. Essentially, this investigation attempted to identify the most appropriate size of the embedded ring that can estimate infiltration rates of PC slabs in a reliable manner. To meet the proposed objective, a multi-scale in situ experimental program was designed, in which five infiltration rings of inner diameter ranging from 100 to 580 mm were embedded into three PC slabs of dimensions 3 x2.5 x 0.15 m. A surface infiltration test was also conducted on PC slabs and was found to vary from 0.36 to 1.87 cm/s. The embedded infiltration rate (EIR) was estimated using a falling head permeability test by ponding water above the pavement surface and measuring the time taken to drain. EIRs decreased from 1.36 to 0.27 cm/s with increasing ring diameter from 100 to 580 mm. Field tests also indicated that infiltration rates for smaller ring diameters (180 mm and lower) had higher uncertainty, which was attributed to the inability of achieving optimum compaction efforts inside of smaller rings. Based on the findings, the optimum size for estimating the infiltration rate of PC was found to be 270 mm. It is noteworthy that this diameter is in the range suggested by ASTM C1701, Standard Test Method for Infiltration Rate of In Place Pervious Concrete, i.e., 300 mm. This research helped identify the practicable specimen size that could be utilized by researchers and practitioners to estimate the most reliable field infiltration rates through PC.

Automated summary

This research evaluated the effect of different sizes of embedded rings on the infiltration rate of pervious concrete (PC), finding 270 mm to be the optimal size for estimating PC infiltration rates reliably.