Effect of different factors on propagation of carbon fiber composite cement grout in a fracture with flowing water

•The most significant influence factor of plastic viscosity is cement water ratio.•Grout propagation length decreases with the increase of plastic viscosity.•Grout propagation length increases with flow velocity, grouting pressure and time.•The most significant influence factor of grout propagation length is grouting time.•Joint roughness coefficient has insignificant effect on grout propagation length. Although grouting has been widely used in fractured rock mass, grouting in fractured rock mass with flowing water environment is still a big challenge. In order to get a great grouting effect for the case with flowing water, carbon fiber was added to the cement grout and a new grout for flowing water environment was provided, and a series of grouting test in the fracture with flowing water was conducted. Effects of plastic viscosity, flowing water velocity, grouting pressure and roughness coefficient of joint on the propagation of carbon fiber composite cement grout was analyzed. The test results showed that propagation length of carbon fiber composite cement grout increases with the increase of flowing water velocity, grouting pressure, roughness coefficient of joint and grouting time, and it decreases with the increase of plastic viscosity of carbon fiber composite cement grout. Grouting time has the greatest impact among the five factors. Finally, a fitting equation based on the test results was deduced.