软土地区机场跑道不均匀沉降分析

Differential Settlement Analysis for Airport Runway Foundation on Soft Area

结合浦东机场五跑道工程的勘察及监测资料,论证了深厚软基塑料排水板超载预压的效果,分析了跨古河道机场跑道软基工后不均匀沉降分布特征。结果表明:古河道区域沉降特征不同于正常区域,采用塑料排水板堆载预压对跑道软基深层处理,工后沉降量及差异沉降率基本满足规范要求;但受古河道分布影响,沉降及不均匀沉降加大,应按压缩层厚度分布变化情况,适当增加超载、塑料排水板布设深度或加密布置间距。

Combined with site investigation and monitoring data of the fifth runway in Pudong airport project, this paper demonstrates the validity of surcharge preloading with prefabricated vertical drains （PVDs） in deep soft foundation treatment, and analyzes the distribution characteristics of the differenti al settlement for airport runway foundation across old channel after construction. The results indicate that the settlement law of the old river region is different from the law of the normal region. And the settlement and differential settlement ratio after construction can meet the specification requirement ba- sically. But the settlement and differential settlement in old channel area increase due to the development of thicker layer of clay. Therefore, the appropriately increased overload, PVD layout depth or cryptographic layout spacing is needed according to the distribution of the thickness of compression layer.