珊瑚碎屑颗粒内孔隙特性微观试验研究

Experimental Study on Inner Pore Morphology of Coral Clastic Particles

珊瑚碎屑是一种特殊的岩土材料,其显著特征是存在大量的内孔隙。为了深入揭示珊瑚碎屑内孔隙特性,通过电镜扫描(SEM)和压汞试验(MIP),分别定性和定量化地分析了珊瑚碎屑颗粒表面及内部孔隙形态特征和分布规律。结果表明:珊瑚碎屑存在由珊瑚虫生长和微生物共生形成的两类大小、形态及分布不同的内孔隙;珊瑚碎屑的整体孔隙度为9%-25%,由珊瑚虫生长而形成的孔隙等效直径为10-200μm;由微生物形成的孔隙面孔隙度低,孔隙直径多为4μm以下,且等轴或不等轴孔隙占绝大部分。

Coral clast is a special material in geotechnical engineering,containing massive inner pores.In order to thoroughly determine the inner pore morphology of coral clastic particles,scanning elec‑tron microscope(SEM)and mercury injection test(MIP)were used in this paper,and distributions of surface and internal inner pore morphologies were characterized qualitatively and quantitatively,re‑spectively.The results reveal that two types of inner pores with different sizes,geometry morpholo‑gies and distributions formed by coral polyps and symbiotic microorganism growing process exist in coral clast particles.Inner porosities of coral clast particles range from 9%to 25%,and the equivalent pore diameters of coral polyps growing pores are between 10 and 100μm.In comparison,the symbiot‑ic microorganism growing pores present a low surface inner porosity,with major equivalent pore diam‑eters under 4μm,and equiaxial and unequal axis pores have been the dominant portion.