软基上加筋防波堤的离心模型试验

通过离心模型试验，研究在有无土工织物加筋垫层条件下防波堤和软基的变形性状，得到了地基沉降、隆起及水平位移的分布规律。提出了一种量测筋材张力的新方法，对土工织物在离心试验过程中的应力状态进行了测试。研究结果表明：土工织物加筋垫层能有效地减小地基的侧向位移，有一定的加筋效果：土工织物张力的发挥水平与堤坝的沉降量密切相关，工作状态下其最大强度发挥水平约为52％。

CENTRIFUGAL MODELING OF REINFORCED EMBANKMENTS ON SOFT CLAY

The geosynthetic reinforcing techniques have been widely used nowadays in the design of embankments and foundations on soft clay to maintain stability during or immediately after the construction of the embankment. However,the behaviour of reinforcements on soft clay is far from clear. The objective is to investigate the behaviours of reinforced embankment on soft clay using the technique of centrifugal modelling and to provide a rigorous basis for optimum design of embankments. A series of centrifuge model tests for both unreinforced and reinforced foundations are conducted and behaviours of the subsoil are observed. Based on these tests,the distributions of the horizontal displacement and vertical displacement as well as the dissipation of the excess pore pressure in the clay foundation are obtained. In particular,the effectiveness of the base reinforcement is examined by comparing its behaviour with that of an unreinforced clay foundation. A new technique for measuring the tension induced in the reinforcement was developed and used in centrifuge tests. It is found that a geosynthetic reinforcement is effective in preventing the lateral displacement of the clay foundation,and therefore,may contribute towards the stability of the embankment. In general,the extension of the reinforcement and the settlement of the embankment are consistent,and in the present study,the mobilization of the tension reaches around 52% of the tensile strength.