By taking Xiluodu high arch dam with high water head and large discharge rate as reference,an experimental research on axial forces regularities for change of a single and nine slabs on arch ring was conducted to study characteristics of axial force by considered of anchoring on them being all out of function by uplift force.The study results showed that the mechanism of axial forces generation and transmission was that the slabs shift and locked were induced by uplift forces,then the adjacent slabs could affect constraint axial forces,conversely the axial forces would transfer to the adjacent slabs eventually to arch abutments.Axial forces distribution could be divided into impacting intensity vibration region,upriver and downriver intensity vibration region.In impacting intensity vibration region,time-average of axial force was small,instantaneous maximum was big, and fluctuation intensity was big, therefore slabs could be locked in short time and instantaneous arch formed.But in upriver and downriver intensity vibration region,time-average was big, instantaneous maximum was big,and fluctuation intensity was small,therefore slabs could be locked for a long time and local arch formed.The dominant frequency of slabs was in the low-frequency narrow range of lower 0.2 Hz in these three intensity vibration regions. When inverted-arch plunge pool is in operation,radial displacement should be controlled,the number of locked slabs be reduced, and magnitude of axial forces be in rational range.
