湿陷性黄土掺配煤矸石路基土石混合料路用性能试验研究

Experimental Study on Road Performance of Collapsible Loess Mixed with Coal Gangue Roadbed Soil-rock Mixture

通过对宁夏地区产量丰富的煤矸石与黄土以不同的比例配制土石混合料,研究其作为高速公路路床土的基本性能,利用煤矸石的膨胀性和黄土的湿陷性的耦合作用,解决道路工程中存在的黄土湿陷性问题。试验结果表明:当煤矸石与黄土掺量相同时,土石混合料的最大干密度和最优含水率分别达到最大值1.78g/cm^(3)和最小值14.2%;随着煤矸石掺量的增加,土石混合料的承载能力呈上升趋势,当煤矸石掺量为50%时,CBR值达到9.6%;随着黄土掺量的不断减少,土石混合料的膨胀量呈减小趋势;综合考虑,建议采用30%以上煤矸石掺量的土石混合料作为路基的填筑材料。

Through different proporations of local abundant coal gangue and loess in Ningxia region,the basic properities of the soil as eapreaaway pavement soil were studied.Taking advantage of the coupling of the expansibility of coal gangue and the collapsility of loess,the problem of loess collapsibility in road engineering was solved.The experimental results show that the maximum dry density and the optimum moisture content of the soil-rock mixture reach the maximum value of 1.78 g/cm^(3) and the minimum value of 14.2% respectively when coal gangue and loess content are mixed at the same ratio.With the increase of gangue content,the bearing capacity of soil and rock mixture shows an upward trend.When the gangue content is 50%,the CBR value reaches 9.6%.With the decrease of loess content,the expansion of soil-rock mixture decreases.Considering comprehensively,it is suggested that the soil rock mixture with more than 30%coal gangue should be used as the filling material of subgrade.