Study on evaluation method of mud-pumping of cement concrete bridge deck pavement

Mud-pumping is one of major distresses of concrete bridge deck pavement, which not only influences the riding comfort of vehicles but also affects the appearance of bridge pavement and endangers the whole bridge structure. Although many methods have been used to assess the mud-pumping distress, most of them remain in the qualitative assessment. Relevant researches about testing methods and quantitative assessment approaches are seldom studied. In this paper, Initial Surface Absorption Test (ISAT), X-ray CT technology, and fractal theory are adopted to assess mud-pumping pavement and study the effect of capillary force on the mud-pumping distress. In addition, the influences of voids distribution characteristics on the capillary water absorption capability are discussed. The ISAT result shows that three significant parameters of mud-pumping cores, such as the capillary water absorption mass, the capillary water absorption coefficient, and the ratio of capillary voids to air voids, are markedly different from those of the non-pumped cores. The mud-pumping cores had a relatively higher void ratio of volume ≤ 0.1 mm3, and lower complexity of void. Quantitative evaluation indexes for mud-pumping distress are recommended by this paper.