为解决真空热固结过程中热量与真空负压在土体中衰减而导致土体加固效果不均匀的问题，利用强夯法能改善土体密实度的特性，将真空热固结法与强夯法联合应用于工程废浆的加固处理,通过4组室内模型试验研究不同夯击时机对土体加固效果的影响。结果表明：沉降速率为每3 d沉降4 cm时为最佳夯击时机，土体表面沉降比其他试验组提高26.55%、11.72%和3.74%，对工程废泥浆的处理效果最佳，能有效解决真空热固结下深层土体加固效果差的问题，并提高土体的均匀性。通过微观结构分析发现，合适的夯击时机下，由于土颗粒之间的孔隙重分布，导致土体密实程度更高，十字板剪切强度随之增大。此外，内部孔隙重分布产生微裂缝形成的排水通道对排水有一定的促进作用，进一步提升了固结效果，在合适的夯击时机下，对土体的十字板剪切强度与固结度均有促进作用。

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.

TU447;TU472.7

国家自然科学基金（51878512、52178348）