Full-Scale Experimental Evaluation of the Flood Resiliency of Thin Concrete Overlay on Asphalt Pavements

Abstract

The capacity to resist flooding is one of the critical challenges of pavement resiliency in locations subject to inundation. Flooding increases moisture contents, which weakens most pavement materials. Although the effect of moisture on the mechanical properties of most pavement materials is reversible, the structural damage caused by trafficking applied on the weakened pavement structure is not. The critical time for structural damage is typically after the flood and before “life-line” pavements have dried back when trucks are bringing in relief supplies and hauling out demolition. This fact, together with the increased occurrence of extreme weather events and sea level rise resulting from climate change, emphasizes the need to better understand the impacts of flooding on identified life-line pavements. This paper evaluates the flooding resiliency of thin concrete overlay on asphalt (COA) pavements by studying the effects that water saturation produces on the pavement structure. The research is based on the structural response and distresses measured in five thin COA sections that were instrumented with sensors and tested with a heavy vehicle simulator (HVS) under flooded conditions. The research shows that the flooding did not produce a noticeable change in the structural capacity of the COA, based on the structural response measured under the loading of the HVS wheel and the falling weight deflectometer, but did result in some structural damage to the asphalt base in some of the sections.

Concrete Overlay Strategies for Improving Pavement Resilience

“…While performing these design calculations, the input resilient modulus was varied based on the previously defined theoretical flooding scenarios. Ultimately, the concrete overlay design thicknesses obtained in this analysis were not very sensitive to the strength of the foundation layers, consistent with previous findings for rigid pavements ( 5 , 6 , 11 , 21 ). COA–B thickness did not change as resilient modulus varied from 1,900 to 2,720 psi, while the COA–U designs only varied by 0.25 inches between the lowest and highest resilient modulus values.…”

“…The construction of a concrete overlay has a shorter schedule than reconstruction and the final system behaves similarly to a conventional rigid pavement, including in its resilience to flooding. Testing of COA sections that were subject to flooding at a heavy vehicle simulator facility in California found that the structural response of the COA sections prior to loading was unaffected by flooding and that they exhibited excellent performance under loading ( 21 ).…”