CAJ | 학술논문

针对安徽张庄矿尾矿坝填料膨胀土进行含水率、自由膨胀率δe f、膨胀力Pe和50 kPa压力下的有荷膨胀率δeP50试验，确定膨胀土的膨胀潜势及分布范围，采用掺石灰的方法对土体进行改良并进行击实试验，根据最大干密度和压实度96%制样，研究不同石灰掺量改良土自由膨胀率随养护时间的关系，进行干湿循环试验研究改良土的胀缩变形规律、渗透特性及抗剪强度特性。试验研究结果表明：随着石灰掺量的增加，膨胀土击实后最优含水率逐渐升高、最大干密度逐渐减小；改良土自由膨胀率随着养护时间的增加逐渐减小并于30 d之后趋于稳定；经历6次干湿循环后试样的胀缩变形存在着不可逆性，但掺灰量大于2%的改良土绝对膨胀率小于4%，试样表面无明显裂隙，抗剪强度提高明显，可认为试样膨胀性得到了良好的控制；对于相同石灰掺量的改良土，二次掺灰的改良效果要优于一次掺灰。
침대안휘장장광미광패전료팽창토진행함수솔、자유팽창솔δe f、팽창력Pe화50 kPa압력하적유하팽창솔δeP50시험，학정팽창토적팽창잠세급분포범위，채용참석회적방법대토체진행개량병진행격실시험，근거최대간밀도화압실도96%제양，연구불동석회참량개량토자유팽창솔수양호시간적관계，진행간습순배시험연구개량토적창축변형규률、삼투특성급항전강도특성。시험연구결과표명：수착석회참량적증가，팽창토격실후최우함수솔축점승고、최대간밀도축점감소；개량토자유팽창솔수착양호시간적증가축점감소병우30 d지후추우은정；경력6차간습순배후시양적창축변형존재착불가역성，단참회량대우2%적개량토절대팽창솔소우4%，시양표면무명현렬극，항전강도제고명현，가인위시양팽창성득도료량호적공제；대우상동석회참량적개량토，이차참회적개량효과요우우일차참회。
In order to determine the swelling potential and distribution range of expansive soil filling of tailings dam in Zhangzhuang,Anhui,the moisture content,free swelling ratio δe f,expansive force Pe,loaded swelling rate under 50 kPa δeP50 are analyzed through laboratory tests. This study deals with the relation between free swelling ratio and curing time of different proportion of lime. The cyclic drying and wetting test deals with swelling and shrinkage deformation rule,seepage properties and shear strength of improved soil. The laboratory results showed that optimum moisture content of expansive soil after hit-solid is increasing with the increasing number of proportion of lime,while maximum dry density is decreasing. The free swelling ratio of improved soil is decreasing with the curing time and tends to be stable after 30 days. The nonreversibility of shrinkage deformation rule is decided after six times’cyclic drying and wetting test. The swelling ratio is below 4% while proportion of lime is over 2%. It may be considered that the expansibility and water stability have been well improved through the increasing of shear strength and less obvious fractures of the patterns’surface. Improvement effect of two-step lime-cement mixing is better than one-step for the same proportion of lime.