摘要
为研究纤维加筋和石灰共同改良膨胀土作为路基填筑材料的工程性质,以宁淮高速公路淮安段膨胀土填料为研究对象,通过在天然膨胀土进行石灰砂化的基础上,加入不同比例的纤维,制备不同纤维掺量石灰土土样,分别进行有荷膨胀试验、无侧限抗压强度试验。结果表明,纤维加筋不仅可减小石灰土的膨胀性,还可以提高石灰土的无侧限抗压强度,并确定改良膨胀土中纤维的最佳掺量为0.2%。此外,对最佳纤维掺量的复合改良土进行直剪试验和干湿循环试验,结果表明纤维和土颗粒之间的摩擦力增大使得纤维石灰土的黏聚力c明显增大,且经过多次干湿循环后CBR值和强度指标不再随循环次数的增加而发生变化。综上研究表明,纤维加筋可有效改善石灰土的膨胀性和强度等工程性质,其中0.2%纤维掺量效果最显著。
In order to study the engineering properties of filled soils to use expansive soil improved by lime and fibers,expansive soil was taken from engineering project in Huaian of the Ninghuai Highway.The soil samples were prepared at different percentages of fiber and lime content and experiments of swelling test and unconfined compressive test were done.The results indicated that the presence of fiber gave great rises to the strength and decreased the expansive of lime soils,and the best dosage of fibers was obtained as 0.2%.The direct shear test and dry-wet cycle test were conducted on the fiber-lime treated soils.The test results showed that fibers can increase the friction between the soil particles and fiber,making the c value of fiber-lime treated soils significantly increased and after several times wetting-drying cycles the CBR value and mechanical properties were no longer changed with the increase of the cycles.It therefore was concluded that the addition of fibers and lime mixture can effectively improve the swelling and lime soil engineering properties such as strength and expansive,of which 0.2% fiber content was the most significant effect.
出处
《四川大学学报（工程科学版）》
EI
CAS
CSCD
北大核心
2014年第S2期65-69,共5页
Journal of Sichuan University (Engineering Science Edition)
基金
教育部博士点基金资助项目(20100094110002)
关键词
膨胀土
石灰
纤维
室内试验
expansive soil
lime
fibres
laboratory test
