Evaluation of Performance of Permeable Interlocking Block Pavements
Drainable or permeable pavement systems are rapidly gaining popularity in Japan because of the high level of precipitation and the growing need for measures against the deteriorating road environment. In the field of interlocking block pavements, highly-porous permeable systems are expected to be increasingly used for constructing walkways and other facilities. However, various issues remain to be solved, including the establishment of criteria for evaluating the functions of the pavement system. This paper evaluates the permeability performance of permeable interlocking block pavement. The following findings were obtained: * Loss of joint sand during the on-site permeability test hardly affected the permeation rate. On the basis of these results, there is no need to precisely specify the measurement points for the on-site permeability test of permeable interlocking block pavement. * A correlation was observed between the permeability coefficient obtained in the laboratory test and the permeation rate obtained in the on-site test. It is possible to select a reasonablepermeable interlocking block product that satisfies the requirements for permeable pavement. * The permeability performance of cushion sand hardly affected the permeation rate in the on-site permeability test. * Joint sands having a larger permeability coefficient value tended to have a higher permeation rate, but not significantly. With its many continuous pores, permeable interlocking block pavement offers special characteristics such as water drainage and noise-reduction effects. The authors will continue to develop an appropriate method for evaluating its functions in order to encourage its application.