To address the issue of decreased heat and vacuum negative pressure in soil, which leads to uneven reinforcement effect during vacuum thermal consolidation, the vacuum thermal consolidation combined with dynamic compaction method is applied for engineering waste slurry treatment, and the characteristics of soil compactness can be improved by dynamic compaction method. The influence of different tamping times on the reinforcement effect of soil was studied through four groups of model tests. Results show that when the settlement rate is 4 cm/(3 d), the tamping time is the best, the settlement of soil surface is 26.55%, 11.72% and 3.74% higher than that of other tests correspondingly, and the treatment effect of engineering waste slurry is the best, effectively solving the unsatisfactory reinforcement effect of deep soil under vacuum thermal consolidation and improve the uniformity of soil. Combined with the results of microstructure analysis, it can be found that due to the redistribution of pores between soil particles, the soil density is higher, and the shear strength of the cross plate increases accordingly under the appropriate tamping time. In addition, the drainage channels formed by the micro-cracks generated by the redistribution of internal pores can promote drainage and further improve the consolidation effect. Therefore, the shear strength of the cross plate and degree of consolidation of the soil can be enhanced under the appropriate tamping time.