Call number: LD2668 .T4 1985 T33 / Master of Science

The primary objective of this study is to evaluate the clogging potential of installed pervious concrete systems, to analyze rehabilitation techniques and develop construction specifications for the construction of portland cement pervious concrete specific to the state of Florida. Currently, a consistent statewide policy has not been established in reference to credit for storage volume within the voids in pervious concrete and the coarse aggregate base. For this reason a current and updated assessment of pervious pavement is needed to benefit from the advantages of pervious pavement use in low traffic volume areas. Initially by modeling a pervious concrete system in a field laboratory with test cells of typical Florida soil conditions and groundwater elevations and combining these data with field data from multiple sites of long service life, a Florida specific construction methodology has been developed. It is hoped that by developing a more standardized design criteria for pervious pavements in Florida a statewide acceptance of portland cement pervious pavement can be achieved and credit can be earned based on the volume of stored stormwater. This study of field sites was subsequently expanded to include locations in the southeastern United States. Pervious concrete has suffered historically poor support due to a number of factors, including concern about poor long term performance due to clogging of surface pores. Eight existing parking lots were evaluated to determine the infiltration rates of pervious concrete systems that have had relatively no maintenance. Infiltration rates were measured using an embedded single-ring infiltrometer developed specifically for testing pervious concrete in an in-situ state. The average infiltration rates of the pervious concrete that was properly constructed at the investigated sites ranged from 0.4 to 227.2 inches per hour. A total of 30 pervious concrete cores were extracted and evaluated for infiltration rates after various rehabilitation techniques, including pressure washing, vacuum sweeping and a combination of the two methods, have been performed to rehabilitate the infiltration capability of the concrete. By evaluating the effectiveness of these rehabilitation techniques, recommendations have been developed for a maintenance schedule for pervious concrete installations. In most cases it was found that the three methods of maintenance investigated in this study typically resulted in a 200% or greater increase over the original infiltration rates of the pervious concrete cores. It is therefore recommended that as a general rule of thumb one or a combination of these rejuvenation techniques should be performed when the system infiltration rates are below 1.5 inches per hour to maintain the infiltration capability of pervious concrete pavements.