聚苯乙烯泡沫塑料颗粒-膨胀土混合料的胀缩特性试验研究  

EXPERIMENTAL STUDY OF SWELL-SHRINKING CHARACTERISTICS OF THE MIXTURE OF EPS GRANULES AND EXPANSIVE SOIL

作　　者：刘宇翼[1,2] 周国庆[1] 苏运河[2] 佘跃心[2] 杨琴[2] 蒋园豪 张恒[2] 

机构地区：[1]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221116 [2]淮阴工学院建筑工程学院,江苏淮安223001

出　　处：《工业建筑》2017年第5期90-95,共6页Industrial Construction

基　　金：国家重点基础研究发展计划(2012CB026103);住房与城乡建设部科技项目(2014-K3-030);江苏省政策引导类计划(产学研合作)项目(BY2016061-12);江苏省建设系统科技项目(2016ZD29)

摘　　要：为减少膨胀土所引起的工程地质灾害,同时实现废弃资源的循环利用,将不同配比聚苯乙烯泡沫塑料颗粒(EPS颗粒)与不同膨胀势的膨胀土制成混合料,开展聚苯乙烯泡沫塑料颗粒改良膨胀土的试验研究。结果表明:聚苯乙烯泡沫塑料颗粒-膨胀土混合料在吸水过程中无荷载膨胀率、有荷载膨胀率逐渐增大,且都经历了快速膨胀期、缓慢膨胀期和膨胀稳定期3个阶段;聚苯乙烯泡沫塑料颗粒-膨胀土混合料的自由膨胀率、膨胀率和膨胀力随聚苯乙烯泡沫塑料颗粒掺量的增大而显著降低,膨胀特性指标与聚苯乙烯泡沫塑料颗粒掺量之间近似呈线性关系;聚苯乙烯泡沫塑料颗粒掺量对中膨胀潜势膨胀土收缩系数影响较小,而对强膨胀潜势膨胀土影响明显;从膨胀力改良效益角度考虑,中膨胀潜势膨胀土中聚苯乙烯泡沫塑料颗粒的最优掺量为5%,强膨胀潜势膨胀土中聚苯乙烯泡沫塑料颗粒的最优掺量为10%。聚苯乙烯泡沫塑料颗粒改良膨胀土的机理主要在于聚苯乙烯泡沫塑料颗粒为膨胀土胀缩变形提供了空间以及柔性材料吸收了膨胀能量。In order to reduce geological disasters caused by expansive soil, and achieve cyclic utilization of waste resources, the mixture was made from different ratio of expanded polystyrene granules（ EPS granules） and expansive soil with different swelling potential, and the tests were conducted to improve expansive soil with EPS granules. The experiments results showed that the swelling ratio of expansive soil without pressure and under pressure increased gradually in the process of absorbing water, and swelling curves experienced three stages： rapid swelling, slow swelling and stable period. The free swelling and swelling force observably decreased with increase of the content of EPS granules and a good linear relation presented between the two; for expansive soil with moderate swelling potential, the volume shrinkage granules ratio was less affected by EPS granules content, but for expansive soil with high swelling potential, the influence was obvious. Considering the efficiency, 5% was the best granules ratio of waste EPS grannies in the mixture for expansive soil with moderate swelling potential, and 10% was the best for expansive soil with high swelling potential. The key point of the mechanism for improving the expansive soil by EPS granules was the good compressibility of EPS granules ratio, which provided space and flexible material to absorb swelling energy from expansive soil and to realize control swell-shrink deformation.

关 键 词：膨胀土 EPS颗粒 膨胀率 膨胀力 收缩系数 

分 类 号：TU411[建筑科学—岩土工程]