Field and Laboratory Investigations of Factors Causing Premature Damage in Urban Cement Concrete Pavements: A Case Study

Research on material-induced factors in premature distress of urban cement concrete pavements in seasonal frost regions remains insufficient. This study selects four typical road sections exhibiting premature distress with varying service ages and structural configurations. The investigation combines field visual inspection and ground penetrating radar scan to identify internal damage locations, which informs core sampling strategies. Through core sample observations, the surface resistivity test, the drop absorption test, the low-temperature differential scanning calorimetry test, and the rapid air test, this research systematically evaluates the concrete’s permeability, chemical durability, and freeze–thaw resistance. The findings indicate that cracks and failed joints may provide pathways for the ingress of moisture and contaminants, promoting the corrosion of reinforcement and internal materials, thereby accelerating pavement failure. The formation of calcium oxychloride (CAOXY) from reactions between deicing salts and cement paste is identified as a primary contributor to premature failure. Even with low chloride ion penetrability and poor water absorptivity demonstrated by the pavement materials, CAOXY content in all investigated areas exceeds the safety threshold. A notable spatial correlation exists between cracking and localized CAOXY enrichment. CAOXY content in concrete at or adjacent to cracks is higher than in concrete distant from cracks. Chlorides likely penetrate through cracks and accumulate internally, leading to significantly increased CAOXY formation in cracked areas. Furthermore, freeze–thaw durability evaluation methods based on air-void parameters prove inadequate for predicting concrete performance in deicing salt environments. The expansive force from CAOXY formation exceeds the buffering capacity of the concrete’s air-void system, further accelerating freeze–thaw damage and resulting in premature pavement failure.