砂土介质中废旧轮胎加筋条带拉拔特性

为减少废旧轮胎大量堆放对环境造成的严重污染及潜在安全隐患,基于废旧轮胎良好的抗拉伸、耐老化及界面粗糙等特性,本研究提出将废旧轮胎切割成条,制成加筋条带,用作土工加筋材料的新型利用方法。通过调整砂土不同密实度条件,对比开展废旧轮胎条带及土工格栅拉拔特性试验研究。结果表明,砂土介质中废旧轮胎条带达到极限拉拔力之前,拉拔位移随拉拔力的增长而线性增长;极限拉拔力统计表明,加筋条带界面抗剪强度符合摩尔-库仑强度准则,并由此建立界面抗剪强度与界面摩擦角及似黏聚力的线性关系。通过对比土工格栅加筋性能,发现废旧轮胎条带的剪应力峰值约为土工格栅的2.5~3.2倍;达到剪应力峰值所需要的位移约为土工格栅的5倍。研究成果验证了废旧轮胎条带作为加筋材料的可行性,为进一步开展理论研究及工程应用奠定了基础。

The pullout features of reinforced strips of waste tires in sandy media

In order to reduce the serious pollution to the environment and the potential safety hazards caused by the large amount of accumulated waste tires, a new method was proposed by cutting tires into strips to utilize the strips as reinforced material due to the good tensile stiffness, strong aging resistance and rough interface properties of waste tire. By adjusting the conditions of different density of sand, a comparative study on the pull-out characteristics of waste tire strips and geogrids was carried out. It was observed that the pullout load-displacement curve showed a tendency of linear increase before the strip of waste tires in the sand medium reaching the maximum pullout resistance. The static analysis of peak pullout resistance revealed that the shear properties of the tire strip-sand interface complied with mohr-coulomb criterion, thus the linear relationship between interface shear strength and interface friction angle, like-cohesion was established. By comparing the reinforcement performance of geogrid, it was found that the peak shear stress of scrap tire strip was about 2.5~3.2 times that of geogrid; the displacement of the peak shear stress was about 5 times that of geogrid. The research results verified the feasibility of used tire strips as reinforcing materials, and laid the foundation for further theoretical research and engineering applications.