Experimental analysis of mechanical properties of loess improved by coal gasification slag
The amount of coal gasification slag increases year by year,while its utilization rate is low.In the meantime,a lack of appropriate sand and gravel and other raw materials exists in civil construction and road projects in northwest region in China.Facing this problem,a countermeasure of utilizing the coal gasification slay improved loess as subgrade fill was proposed.Based on the unconfined compressive strength test,direct shear test,consolidation test and collapsibility test of loess,the mechanical properties of improved loess with different coal gasification coarse slag content and different curing ages were analyzed.The results show that,when the dosage of coarse coal gasification coarse slag is 6%and the curing age is 28 d,the compressive strength of loess increases from 364 kPa to 568 kPa,indicating a growth rate of strength up to 56%.Additionally,the cohesion of loess increases from 42.1 kPa to 81.8 kPa,and the growth rate of cohesion is up to 94.3%.When the coal gasification coarse slag content is 6%,the compressive coefficient of loess decreases from 0.33 MPa-1 to 0.11 MPa-1,with a decrease rate of 66.7%.With the increase of coal gasification coarse slag content,the collapsibility coefficient of the improved loess decreases first and then gradually increases.When the percent-age of coal gasification coarse slag is 6%,the collapsibility coefficient of the loess decreases from 0.035 to 0.016,and it is with a decrease rate of 55%.Thus,under the condition of 6%coal gasification coarse slag content and 28 d curing period,the unconfined compressive strength and shear strength of coal gasification coarse slag modified loess are significantly increased,while the compres-sion coefficient and collapsibility coefficient of coal gasification coarse slag improved loess are significantly decreased.
万方数据
维普
