软弱岩体中疏水性聚合物的运移吸附及扩散传质机理研究

Migration adsorption of polymer slurry in interface and diffused mass transfer in the fracture of the weak rock mass are the basic reason of polymer permeation grouting for the anti-seepage and reinforcement of the weak rock mass. This research project mainly focuses on the hydrophobic polymers. Polymeric permeation grouting is assumed to be the migration adsorption and diffused mass transfer of immiscible two-phase flow in saturated porous media with low permeability. This research project plans to achieve the visualization research on the polymeric permeation grouting by solid-state nuclear magnetic resonance imaging in situ, quartz crystal microbalance with dissipation, microscopic pore CT three-dimensional imaging and three-dimensional network model reconstruction by using the basic theories of interface seepage, two-film and two-phase flow diffusion mass transfer. The properties of molecular level and micro mechanics of the hydrophobic polymers are researched to study on the adsorption, desorption and dynamic film forming rule in the interface of rock mass particle. The interfacial penetration mechanism of the solid-liquid membrane between the rock particles and binding water as oil drop and the mechanism of competitive migration adsorption for the binding water are investigated to get the unified migration adsorption-diffused mass transfer mathematical model of the hydrophobic polymers in the weak rock mass. Through the study, the theoretical and scientific supports can be provided to research and develop the suitable polymeric permeation grouting materials, equipments and technologies for the weak rock mass.

高分子渗透灌浆防渗加固软弱岩体的实质，是高分子浆液在软岩界面的运移吸附和软岩裂隙中的扩散传质过程。项目以疏水性聚合物为研究对象，拟将高分子渗透灌浆，假定为非混溶两相流，在低渗透饱和多孔介质中的运移吸附和扩散传质过程。通过融合交叉学科的“界面渗透理论”、“双膜理论”和“两相流扩散传质理论”，采用原位固体核磁共振成像、耗散型石英晶体微天平、微观孔隙CT三维成像和三维网络模型重构，实现高分子渗透灌浆的可视化研究。拟考察疏水性聚合物的分子微观力学性能，总结疏水性聚合物在岩体颗粒界面的吸附、解吸和动态成膜规律，探究疏水性聚合物以油滴形式在岩体微粒-结合水的固液膜相间的界面渗透机理，以及与结合水间的竞争性运移吸附机理，建立完整的疏水性聚合物在软岩介质内的运移吸附-扩散传质数学模型。以期为开发适合于软岩地层的高分子渗透灌浆材料、设备和施工技术，提供较系统的理论基础和科学依据。

软岩介质，已成为制约重大工程顺利建设和安全运营的主要工程技术难题。注浆技术，属于一种解决上述难题常用和有效的治理技术。然而，由于软岩地层条件的复杂性和注浆工程的隐蔽性，使得注浆技术的发展还很不成熟，注浆设计和施工存在一定的盲目性。本项目通过QCM-D平台构建和Gaussian结果，证实了岩体水化界面的活化硅羟基，可以和疏水性聚合物上面的活性基团形成强氢键。基于计算机高分辨断层扫描成像技术 (Micro-CT)，对注浆材料固结体进行了扫描及数字注浆材料固结体3D重构，并且分别用等效球法和最大球法对样品进行了孔网构建，并对微观孔隙进行了结构特征分析。本项目采用有限元方法求解了流场和输运场控制方程，利用Galerkin有限元法建立了连续模型方程在空间上的离散形式，并初步建立了完整统一的传质理论和数学模型。本项目研究工作的成果主要反映在目前9篇已出版的SCI收录论文和获得的2项省部级科技奖励。