Abstract: In grouting reinforcement of water-rich and broken rocks, it is difficult to use the traditional cement-based material to simultaneously achieve water plugging and reinforcement. To solve the above problems, a kind of cement-based composite grouting material (CGM) is developed by using sulphoaluminate cement clinker and steel slag powder. The performances of traditional material and CGM are compared, based on the experimental results of the scanning electron microscope and X-ray testing methods. The effect of preparation methods, constituent contents and slurry preparation conditions on the performance (strength, volume stability and slurry viscosity) of CGM is systematically analyzed, and the feasibility and management effect of CGM are also examined with combination of field applications. The results show that the CGM should be prepared by the process of mixed grinding (less than 45 min), so that its hydration activity can be significantly improved. With the increase of the amounts of steel slag powder and the water-cement ratio, the required setting time increases and the strength decreases. It is found that there exists a late dry shrinkage phenomenon when water-cement ratio exceeds 1.2. Compared with traditional cement materials, the setting time and viscosity of the new CGM material are less sensitive to the environment, showing the good performance of the CGM material.

Key words: sulphoaluminate cement clinker, steel slag powder, grouting material, performance test, engineering application