Moisture increase in the subgrade and base layers of a pavement section is one of the main causes for its premature distress and failure. Infiltration, capillary rise and lateral moisture transfer constitute the major sources of the increased water content. An investigation was conducted with the objective of mitigating the severe effects of increased moisture by installing a geotextile with enhanced lateral drainage (ELD) characteristics in pavements subject to capillary rise from a high-water table. Specifically, an accelerated pavement-testing program was conducted at The University of Texas at Austin laboratories to assess the benefits of an ELD geotextile in decreasing the moisture in the pavement layers and thus improving its performance. A Model Mobile Load Simulator (MMLS3) device was used to load a six-foot by six-foot by one-foot pavement section consisting of kaolinite subgrade and unbound base. A hydraulic system was designed to establish a constant water level in the pavement and allow for capillary rise in the subgrade and base layers. Three different configurations were tested with ELD and conventional geotextiles installed at the subgrade and base interface. The configurations were initially evaluated hydraulically through the evaluation of column tests constructed using the same configuration of soils and geotextiles to be constructed in the MMLS3 device. The pavement performance was assessed by monitoring changes in volumetric moisture content, particle movements, and pavement rutting. The test results showed that installing the ELD geotextile improved the pavement performance, highlighting the effectiveness of the ELD geotextile in draining the extra moisture and reducing distresses.
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