Repetitive Loading Tests on Membrane-Enveloped Road Sections During Freeze-Thaw Cycles

Road test sections of impermeable membrane-enveloped silt and clay soils overlain with asphalt cement concrete were subjected to repetitive dynamic plate-bearing loadings to determine strength variations of the pavement systems during freeze-thaw cycles. The modulus values of the asphalt cement concrete vary inversely with its temperature by an order of magnitude (90,000 psi to 1,300,000 psi) in the temperature range of 110°F to 30°F. The resilient stiffness of the pavement system varied in the same manner by nearly a factor of eight (228.4 kips/in to 1,740.2 kips/in. Despite the wide strength variations of the sections during freeze-thaw cycles, membrane enveloped fine-grained soils can be utilized instead of granular materials as base and subbase layers in flexible pavements in cold regions where moisture migration is a major concern. Without the membrane protection such fine-grained soils that experience frost heaving suffer severe bearing strength loss during thawing.