On compression behavior and particle breakage of carbonate silty sands
On compression behavior and particle breakage of carbonate silty sands
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DOI：
10.1016/j.enggeo.2021.106492
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发表时间：
2021-12
影响因子：
7.4
通讯作者：
Chenxi Tong;Zongwei Dong;Quan Sun;Shengxi Zhang;Junxing Zheng;D. Sheng
中科院分区：
文献类型：
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作者：
Chenxi Tong;Zongwei Dong;Quan Sun;Shengxi Zhang;Junxing Zheng;D. Sheng
碳酸盐土具有高压缩性和低颗粒强度，因此在许多岩土工程应用中需要特殊处理。通过一维压缩试验，研究了不同初始粒径分布和不同初始孔隙比的碳酸盐土在32 MPa高有效竖向应力下的压缩特性和颗粒破碎特性。一个明确的形状过渡方面的空隙比对有效的垂直应力观察到不同的粉粒分数和空隙比。粉粒含量低、孔隙比大的土样，其变形机制主要是颗粒破碎引起的解锁效应。粉粒含量高、孔隙比低的试样颗粒破碎程度较低，其变形机制主要是颗粒间的锁定效应。一个“过渡”的行为模式，没有一个独特的正常压缩线被确定为样本的粉粒分数范围从1.6%到33%。研究还发现，具有“过渡”和“非过渡”压缩行为模式的碳酸盐土样品都可能经历相当数量的颗粒破碎，并在颗粒形状的演变中表现出不同的趋势。
Carbonate soils are high in compressibility and low in particle strength, and therefore need special treatment for many geotechnical applications. This paper presents comprehensive one-dimensional compression tests to investigate the compression behavior and particle breakage of carbonate soils with various initial particle size distributions (PSDs) and a wide range of initial void ratios at a high effective vertical stress of 32 MPa. A clear shape transition in terms of the void ratio against effective vertical stress was observed with varying silt fraction and void ratio. The deformation mechanism for the samples with less silt fraction and higher void ratio is mainly dominated by the particle-breakage-induced unlocking effect. Samples with more silt fraction and lower void ratio will experience less particle breakage and their deformation mechanism is mainly attributed to interparticle locking effect. A ‘transitional’ mode of behavior without a unique normal compression line was identified for the samples with silt fraction ranging from 1.6% to 33%. It was also found that carbonate soil samples with both ‘transitional’ and ‘non-transitional’ modes of compression behavior may both experience considerable amount of particle breakage and show different trends in the evolution of particle shape.