Study on performance and applicability of curtain grouting materials in karst fractured stratum

Aiming at the grouting treatment project of water inrush disaster in the karst fractured strata in a coal mine in Huaibei mining area， a study on the performance and applicability of curtain grouting material suitable for the karst fractures developed strata was carried out.By conducting laboratory tests， the fundamental characteristics of Portland cement single-portion cement slurry， cement-fly ash slurry， cement-fly ash-clay slurry and the best mix ratio of them were studied.According to the stratum properties of the coal mine and the requirements of the curtain grouting diffusion mode， the applicabilities of grouting materials were studied systematically from the aspects of material property， technical feasibility， grouting process control， treatment effectiveness and economic environmental protection.It provides reference and guidance for the selection of engineering grouting materials.The results show that the slurry water-solid ratio is the main controlling factor that affects the basic performance indicators such as strength， viscosity， calculus rate and setting time of the slurry stone.The mixing ratio of fly ash and clay will also affect the basic performance parameters of the material.According to the proposed appraisal method for the applicability of grouting materials and the performance parameters of different types of materials with different proportions， grouting parameters such as grouting materials and mixing ratios in different sections were determined， and the inrush water in the mine area was effectively blocked.