A Novel Laboratory Test Method to Measure Dynamic Water Pressure Underneath a Cracked Concrete Pavement

Abstract

Water infiltration through a discontinuity (crack/joint) in a pavement generates water pressure at the end of the discontinuity when experience traffic load. If this discontinuity extends to the full depth, the generated water pressure can lead to deterioration of foundation material, which ultimately can create under stab voids resulting poor load transfer efficiency and failure of the pavement. A novel laboratory test has been developed to measure water pressure underneath a flooded concrete slab that contains 2mm continuous pore across the full depth. The slab was subjected to dynamic load of a 5kN and 10kN, applied at four different frequencies, 1Hz, 5Hz, 10Hz and 15Hz. Excellent repeatability has been achieved on measuring pore water pressure. The results also showed that pore water pressure increases with increasing load frequency, but the influence of load magnitude and the depth of surface water was found to have only marginal impact.