Effect of continuous load and lithium slag on gas permeability of concrete
In order to study the effects of continuous compressive load and lithium slag admixture on the gas permeability of concrete at different ages,concrete with different lithium slag admixtures of strength classes C20,C30 and C40 were designed,and 0.1,0.3 and 0.5 times of the ultimate compressive stress of the specimens were taken as the test applied continuous load,and the compressive strength and gas permeability coefficients of the specimens at ages of 7 d,14 d,28 d and 56 d were measured.By analyzing the changes of gas permeability coefficients of the specimens under different levels of continuous compression loads,it was found that the gas permeability coefficients of the specimens fluctuated when the stress ratio was below 0.3.After the stress ratio was greater than 0.3,the gas permeability coefficients increased significantly.When the stress ratio is below 0.3,10%of lithium slag can significantly reduce the gas permeability coefficient of the specimens,indicating that the appropriate amount of lithium slag can effectively reduce the degree of internal pore connectivity of concrete and inhibit the development of concrete microcracks under stress.