Research and development of high strength acrylic salt grouting material suitable for water-rich strata of ultracataclasite and study on permeability reinforcement characteristics

Aiming at the problems of strong disaster caused by water-rich dense weak surrounding rock and weak applicability of conventional grouting materials, a new type of high-strength acrylic acid grouting material was developed, its polymerization reaction mechanism and working performance were analyzed, and the permeability and reinforcement characteristics of the new material on dense pulverized silty rock were studied. Based on the organic-inorganic interpenetrating network method, the high strength acrylic acid grouting material was developed, which was composed of main agent, inorganic modifier, initiator, accelerator, crosslinking agent and other raw materials, and had the remarkable characteristics of high strength and high permeability and the polymerization reaction of the two components of the high strength acrylate material was sufficient after mixing, and the inorganic network structure was evenly interspersed in the acrylate organogels network; According to the orthogonal test, the characteristics of the new materials with different compositions, such as the gelling time, compressive strength and water absorption expansion rate, as well as the influence rules of the components, were obtained. The gelling time range of the slurry was 45 ~ 201 s, the uniaxial compressive strength of the gel was 1.2 ~ 2.1 MPa, and the water absorption expansion rate was 16 ~ 51%. The sensitivity ranking of factors affecting the main working properties of the new materials is further clarified; In accordance with laboratory tests and EDX energy spectrum analysis technology, the permeation and reinforcement characteristics of grout in dense crushed rock were studied. The results showed that the permeation and diffusion capacity of high-strength acrylate grout was close to that of pure acrylate grout, which was much higher than that of cement grout. Moreover, high-strength acrylate material had an obvious coating and strengthening effect on crushed rock particles, and the solid strength reached 2.31 MPa. It is 5.4 ~ 11.0 times the reinforcement strength of pure acrylic salt material, which can provide a strong safety guarantee for tunnel disaster grouting control and safe excavation.