Research On Rheological Properties Of CL-C Clay Cement Slurry

CL-C clay cement slurry is widely used in coal mine grouting engineering because of its good injectability and excellent performance.However,the determination of grouting pressure,diffusion radius and other parameters depends on empirical formula,and most of them can not meet the needs of engineering reality.Therefore,it is necessary to systematically study the rheological properties of CL-C clay cement slurry to guide the reasonable selection of grouting parameters.Firstly,the constitutive test is designed and three rheological models are used for fitting analysis.The results show that CL-C clay cement slurry conforms to Bingham flow pattern,and the Bingham flow pattern can be maintained with the continuous flow time.At the same time,the amount of each component of the slurry also has a certain influence on the constitutive model of the slurry.Then through the rheological parameter test,it is found that the yield stress and plastic viscosity of the slurry increase exponentially with the flow time.On this basis,the time-varying constitutive equation of clay cement slurry is constructed based on Bingham flow pattern,and the function equation between grouting pressure and diffusion distance is derived when clay cement slurry diffuses in laminar flow in a single fracture under the condition of fixed pump volume.The rheological test also shows that the slurry has obvious shear dilution effect,and the plastic strength increases with the increase of time under the curing condition.The time-varying characteristics of apparent viscosity and shear stress conform to the power exponential growth mode.Finally,combined with the numerical calculation method,the variation characteristics of grouting pressure with time and distance of single fracture diffusion and the variation laws of grouting pressure and diffusion velocity with time under the condition of different opening and double fracture coupling are further analyzed,which lays a foundation for the fracture grouting model test and the study of grouting diffusion law under the condition of multi fracture coupling.