防波堤土工织物加筋地基离心模型试验及数值模拟

Centrifugal & numerical modeling of geosynthetic reinforced embankments on soft clay

以黄骅港北防波堤工程为依托,对土工织物加筋软粘土地基及斜坡式防波堤体系的固结过程进行了离心模型试验和有限元数值模拟,通过分析地基土体固结过程中防波堤-加筋垫层-基体系的位移场和应力场的发展及织物拉应力分布和发展,验证离心试验及数值模拟方法的合理性,并得出以下几点主要结论:(1)土工织物加筋垫层的作用机理为其抗拉性限制自身横向变形,通过与附近土体的摩擦作用限制其侧向变形;(2)加筋减小防波堤-垫层-地基体系的高应力水平区,避免堤身与地基高应力水平区域的连通,增强系统稳定性;(3)在离心试验采用的分层地基的条件下,加筋减小了浅层软基和堤身的侧向位移量,对系统总位移有抑制作用;(4)试验中织物替代材料的极限拉伸强度发挥程度较低,其与砂垫层间摩擦强度的发挥水平约为23.8％。

The behavior of geosynthetic reinforced embankment on soft clay has been explored using the technique of centrifugal and numerical modeling. During the consolidation of foundation soil, the strain and stress of soil and geotextile are analyzed in the two ways above mentioned respectively. Two series of results are studied by the comparative method and show that (1) the work principle of reinforcement is its tensility limits its own deformation and reduces horizontal displacement of soil nearby through friction; (2) reinforcement dwindles and separates the regions of high shear stress level in embankment-reinforcement-soil system, therefore improves the global stability; (3) reinforcement reduces the whole deformation of embankment and foundation; (4) the mobilization of reinforcement's tensile strength is low and the mobilization of shear strength in the interface is about 23.8 %.