波浪荷载作用下防波堤地基软化特性的试验研究

长江口防波堤在建造期间遭到了强热带风暴的袭击,致使一部分沉箱结构或沉入土中1~5 m,或偏移初始位置20m。本文通过动三轴试验模拟了波浪荷载作用下地基的变化情况,试验结果显示,沉箱的过度沉陷和侧移是由于强风暴使得软粘土强度弱化所引起的。根据试验结果,提出了竖向排水联合堆载预压的方法来加固软土地基,为证明该方法的有效性,在加固的软土地基上对防波堤进行了重建。重建后经历几次强风暴该防波堤无损坏迹象。

Stability analysis on the breakwater in Yangtze Estuary under the action of wave load

During constructing the guiding dike in Yangtze Estuary, some of the catsson structures were sinking into the soil for 1-5 m or sliding away about 20m from the original place, when a strong storm was attacking this area. Dynamic triaxial tests were carried out to simulate the behavior of foundation soils under wave loading. The test results show that the excessive settlement and lateral movement of the caissons are due to the strength weakening of the soft clay during the strong storm. The test results also show that the ability of the soft clay to resist the wave force will be greatly increased when the soft soil samples were suitably improved. Based on the test results, an improvement method associating vertical drains with surcharge loading was proposed to strengthen the foundation soil. With the improved soil foundation, the dike has been reconstructed and undergone several strong storms without any damage.