中文摘要：

深厚覆盖层土体原位结构性强,原状样取样困难,且由于粒径、级配的改变,室内重塑样试验确定的力学参数不能反映原位土体的实际性质,如何考虑原位结构效应确定深厚覆盖层土体的力学参数是工程建设中的难题。本文探索了联合现场原位试验和室内重塑样动力特性试验,考虑原位结构效应确定深厚覆盖层土体动强度参数的方法：（1）基于现场试验确定原位土体的动强度基准值;（2）基于室内重塑样试验确定动强度在不同振动强度和固结应力条件下的变化规律;（3）结合室内动力试验确定的动强度参数变化规律,将基于现场试验确定的动强度基准值推延至多种震级和应力条件。以某实际深厚覆盖层深埋砂土为研究对象,联合现场标贯试验和室内动三轴试验结果,综合确定了能考虑深厚覆盖层土体原位结构效应的砂土动强度参数,并与室内试验结果进行了对比。研究成果可为该工程坝体—覆盖层地基系统抗震安全评价提供依据,也可供类似工程参考。

英文摘要：

How to accurately determine the mechanical parameters of deep alluvial soils with strong structure is a difficult issue in construction of projects with deep alluvial soils. This paper focuses on the problem by studying how to determine the dynamic strength parameters through comprehensively considering the in-situ tests and the laboratory tests, which include three aspects in： （1） determining the basic dynamic strength of deep alluvial soils with in-situ tests; （2） determining the dynamic strength parameters under different vibration magnitude and consolidation stress conditions with laboratory tests and （3）extending the basic dynamic strength parameters to different magnitude and various consolidation stress conditions based on the results of laboratory tests. Field standard penetration tests and laboratory tests were carried out toward soils of a real deep alluvial layer, then dynamic strength parameters considering in-situ structure effect were determined with method mentioned above, which were compared with those determined by laboratory tests. These research results can provide the basis for seismic safety evaluation of foundation and embankment system, and can also be used as reference for similar projects .