橡胶颗粒掺量对砂土抗剪强度的影响

Effects of Small-sized Scrap Tire Crumb Contents on Shear Strength of Sand

将废旧轮胎加工为橡胶颗粒,并与砂土混合成为混合土,使之更适合作为路堤、挡墙、桥台等填筑工程的填料。通过直剪试验研究了不同废旧轮胎橡胶颗粒掺量(如10%、20%、30%、40%及50%)对细海砂以及中粗砂抗剪强度的影响,探讨了剪切位移与剪应力的关系,分析并比较细砂、中粗砂改良后的抗剪强度变化特征。试验结果表明:当橡胶颗粒掺量小于20%时,细海砂-橡胶颗粒混合土和中粗砂-橡胶颗粒混合土的抗剪强度随废旧轮胎橡胶颗粒掺量增加而增大;反之,细海砂-橡胶颗粒混合土和中粗砂-橡胶颗粒混合土的抗剪强度随着废旧轮胎橡胶颗粒掺量的增加而减小。

Rubber crumbs made from scrap tires were mixed with sand evenly to form the scrap tire crumb-sand mixture,which was more suitable to be used as fill for embankments,retaining walls and bridge abutment.Direct shear tests were conducted to study the effects of different scrap tire crumb contents （10%,20%,30%,40% and 50%） on the shear strength of fine sand and medium-coarse sand.The relationship between shear displacement and the corresponding shear stress was explored and the shear strength changes of the improved fine sand and medium-coarse sand were analyzed.Test results show that the shear strength of both the fine sand-scrap tire crumb mixture and medium-coarse sand-scrap tire crumb mixture increases with the increase of scrap tire crumb content when the content is less than 20%,while the shear strength of both mixtures decreases with the increase of the scrap tire crumb content when the content is more than 20%.