Zhou Dong, Qin Pengfei, Wang Ang, Si Kai
School of Civil Engineering, Zhengzhou University of Technology, Zhengzhou, Henan 450044, China.
Engineering Division, Huanghe Science & Technology University, Zhengzhou 451000, China.
ACS Omega. 2025 Jul 23;10(30):33022-33030. doi: 10.1021/acsomega.5c02233. eCollection 2025 Aug 5.
In the construction of tunnels, water conservancy, mining, and other engineering projects, the water-rich weathered sandstone with large porosity, strong permeability, and highly developed fissures is often exposed, which brings a great threat to construction safety. The method of grouting can greatly reduce the occurrence of such disasters, thereby improving the safety and reliability of related projects. Based on this, the paper considered the disorder and random uncertainty of sandstone fractures and established a theoretical model between sandstone hydraulic conductivity and fractal dimension based on fractal theory. Furthermore, a fractal model for the amount of grouting cement in weathered sandstone was established by considering the injectability of granular grout in fractures, effectively revealing the variation of grouting cement amount with fractal dimension under one- and two-dimensional flow states, respectively. Based on the relationship between cement dosage and hydraulic conductivity, three physically defined grouting areas were defined, that is, the hydraulic splitting zone, the normal grouting zone, and the micro-crack zone. Finally, the Qingdao Metro was selected as the site for verification. The on-site measured data were mainly located in the normal Pearl River area and less in the grouting area A, indicating that the grouting feasibility of this area was relatively good. Through the above work, some theoretical guidance can be provided for the construction of weathered sandstone engineering projects.
在隧道、水利、采矿等工程项目建设中，常遇到孔隙率大、渗透性强、裂隙高度发育的富水风化砂岩，给工程施工安全带来极大威胁。注浆法可大幅减少此类灾害的发生，从而提高相关工程的安全性与可靠性。基于此，本文考虑砂岩裂隙的无序性和随机不确定性，基于分形理论建立了砂岩渗透系数与分形维数之间的理论模型。此外，通过考虑裂隙中颗粒浆液的可注性，建立了风化砂岩注浆水泥用量的分形模型，有效揭示了一维和二维流动状态下注浆水泥用量随分形维数的变化规律。基于水泥用量与渗透系数的关系，定义了三个物理意义明确的注浆区域，即水力劈裂区、正常注浆区和微裂隙区。最后，选取青岛地铁作为验证场地。现场实测数据主要位于正常珠江区域，注浆区域A的数据较少，表明该区域的注浆可行性相对较好。通过上述工作，可为风化砂岩工程项目施工提供一定的理论指导。
