Relationship Between Permeability and Microstructure of Cement Bentonite Slurry Concretion

Abstract:

The structure of pores in the concretion of cement bentonite slurry is measured by mercuryinjection method,and the permeability coefficient of the concretion is measured by permeability test.According to the test results,the connections between the permeability and pore structure as well as the dosage of cenment and bentonite in the cement bentonite slurry are analyzed.The analysis reveals that the permeability of cementbentonite slurry concretion is controlled mainly by critical size of pores in the concretion.The smaller the critical size of pores,the stronger the permeability resistance of the concretion is,and other pore structure parameters have little influence on the permeability of the concretion.With the increase of the dosage of cement and bentonite,the critical pore size of the concretion will gradually decrease,and the dosage of cement has greater influence on the critical size of pores than that of bentonite.

Key words:cementbentonite slurry concretion; microstructure; critical size of pores; permeability coefficient; mercuryinjection method