Water Runoff Characteristics in Porous Block Pavements Using an Accelerated Pavement Tester

Abstract

Permeable block pavements are designed to treat and delay the water flow in an urban environment. In order to measure the runoff characteristics of the permeable block pavement, a rainfall simulation test was conducted at the accelerated pavement testing facility. This paper focuses on determining the runoff characteristics in terms of the permeability coefficients of the block pavements under different rainfall conditions, such as rainfall intensity, quantity, and time intervals. In this study, four different pavement test sections were constructed and their runoff coefficient values were determined as follows: (1) 0.19-0.45 for the porous block-porous cement treated base (CTB) section, (2) 0.27-0.61 for the porous block-dense CTB section, (3) 0.50-0.78 for the dense block-porous CTB section, and (4) 0.77-0.85 for the dense block-dense CTB section. Particularly, when the rainfall intensity increased from 60 to 200 mm/h on the porous block pavement, 5-45% additional surface runoff occurred. Further, 20% more surface runoff occurred in the saturated surface condition compared to the dry condition. (C) 2014 American Society of Civil Engineers.