基于渗率效应的可压缩智能同步注浆材料扩散机理研究

Diffusion Mechanism of Compressible Synchronous Grouting Materials Based on Permeability Effect

摘要:

目前同步注浆材料采用水泥砂浆作为注浆材料，注浆和固结过程中浆液在土体中渗透，导致浆液体积减少，若后续注浆不及时，极易造成盾尾间隙注浆不密实。而轻质智能同步注浆材料含气泡，其具有压缩“弹性”，随着浆体的固结卸荷，虽然有部分浆体扩散，但浆体在盾尾间隙中体积保持不变，保证了同步注浆密实度。研究了轻质智能同步注浆材料密度与压力的映射关系，建立了轻质智能同步注浆材料压缩理论模型。定性分析了轻质智能同步注浆材料高密实度注浆原理。针对轻质智能同步注浆材料成分特征，建立了基于渗滤效应的可压缩智能同步注浆材料的固结扩散机理。研究表明：可压缩同步注浆材料随着压力增大，浆液体积逐渐减小，通过实验验证，轻质材料压力?密度曲线可变参数与气泡含量具有较强的相关性。地层渗透系数对浆体固结扩散距离具有显著影响，地层渗透系数越大，轻质智能同步注浆材料固结扩散距离受土体力学性质影响越显著。

Abstract:

At present， cement mortar is used as the grouting material for synchronous grouting， and the slurry permeates in the soil during grouting and consolidation， resulting in the decrease of slurry volume. If the subsequent grouting is not timely， it is easy to cause the grouting of shield tail gap not to be dense. The lightweight intelligent synchronous grouting material contains bubbles， because of its compression “elasticity”， with the consolidation and unloading of the slurry， although some of the slurry diffuses， the volume of the slurry remains unchanged in the gap between the tail of the shield， ensuring the density of the synchronous grouting. In this paper， the mapping relationship between density and pressure of the lightweight intelligent synchronous grouting material is studied， and the theoretical model of compression of lightweight intelligent synchronous grouting material is established. The principle of high density grouting of lightweight intelligent synchronous grouting material is qualitatively analyzed. According to the composition characteristics of lightweight intelligent synchronous grouting material， the consolidation and diffusion mechanism of compressible intelligent synchronous grouting material based on percolation effect is established. The results show that the volume of the slurry decreases with the increase of the pressure of the compressible synchronous grouting material. The experimental results show that the variable parameters of the pressure-density curve of the lightweight material have a strong correlation with the bubble content. The formation permeability coefficient has a significant influence on the consolidation diffusion distance of slurry. The larger the formation permeability coefficient is， the more significantly the consolidation diffusion distance of lightweight intelligent synchronous groutingmaterial is affected by the soil mechanical properties.