Abstract: The disposal and resource utilization of river sediment are key to ensuring engineering safety and environmental quality. This article follows the concept of "reduction and harmlessness" of sludge and proposes a vacuum preloading radiation electroosmotic technology that combines dewatering and heavy metal removal functions. In order to systematically illustrate the dewatering effect and heavy metal removal mechanism of vacuum preloading radial electroosmotic technology in sludge treatment, this paper establishes a heavy metal ion migration model based on Coulomb's law. By comparing the heavy metal ion migration mechanisms of radial electrode electroosmotic method and traditional vertical electrode electroosmotic method, it is proved that radial electrode electroosmotic method has a faster ion migration speed, which effectively shortens the migration path under the same working distance and improves the efficiency of heavy metal ion treatment. In addition, we independently develop a model device for vacuum preloading radial electroosmotic technology and radial electrodes, and conducted experiments on vacuum preloading electroosmotic method, vacuum preloading cathode radial electroosmotic method, vacuum preloading anode radial electroosmotic method, and vacuum preloading anode cathode radial electroosmotic model. We analyze the changes in indicators such as drainage volume, settlement volume, vane shear strength after dewatering, moisture content, consolidation degree, and heavy metal Cu content. Research has shown that compared to traditional vertical electrodes, the use of radiation electrodes has significant advantages in dewatering and heavy metal removal of sludge. In terms of dehydration, within 48 hours of starting electroosmosis, vacuum preloading cathodic radiation electroosmosis, vacuum preloading-anode radial electroosmosis, and vacuum preloading-cathode-anode radial electroosmosis increased drainage by 3.09%~6.93% and final settlement by 3.26%~7.07% compared to vacuum preloading electroosmosis. At the same time, the difference in water content on the soil surface is significantly reduced, and the vane shear strength increases by up to 21.38%. In terms of heavy metal ion removal, the removal effect of Cu increases by 8.15%~21.66%. The research results can broaden the application scope of traditional vacuum preloading technology and provide a scientific reference for green and safe design and construction of foundations.