沼泽相泥炭质土十字板抗剪强度的应用研究

Field Vane Shear Strength Tests in Marsh Peat Soils

为了评价泥炭土地基高填方路基施工过程的稳定性,结合某泥炭土地基高填方机场跑道工程,开展泥炭土室内物理力学指标试验和现场十字板剪切试验。分析区域沼泽相泥炭土的工程特性,对比分析中美十字板剪切试验仪器设备和抗剪强度指标修正方法的异同,论证泥炭质土十字板剪切强度沿深度的变化规律和泥炭土沉积不均匀特性,线性回归十字板抗剪强度指标与土体抗剪强度指标之间的关系。采用不同抗剪强度指标计算泥炭土地基的稳定系数,提出泥炭土地基高填方作业地基稳定计算指标的选取原则,对本区域类似工程建设具有借鉴意义。

To evaluate the stability of the high embankment over marsh peat soils,this paper presents a case history of a high fill airport runway project in peaty soils.The physical and mechanical property laboratory tests and in-situ vane shear test were performed.The engineering characteristics of peaty soils of tidal marsh phase in this region were analyzed.The similarities and differences of the shear strength index correction methods of the vane shear test between China and the United States were compared and evaluated,to demonstrate the variation of the vane shear strength along the depth and the heterogeneous of the peat soil deposition,as well as to linearly regress the relationship between the vane shear strength index and the shear strength index of the soil mass.Different shear strength indexes are used to evaluate the factor of safety of the peaty soil embankments.The principle of the high fill embankment stability evaluation is proposed,which is of reference significance for the construction of similar projects in the region.