含水合物土一维压缩特性  

Properties of one-dimensional compression for hydrate-bearing soil

作　　者：颜梦秋 黄永茂 顾翔 颜荣涛[1] 杨德欢[1] 于海浩[1] 徐玉博 陆地 YAN Mengqiu;HUANG Yongmao;GU Xiang;YAN Rongtao;YANG Dehuan;YU Haihao;XU Yubo;LU Di(Guangxi Key Laboratory of Geomechanics and Geotechnical Engineering,Guilin University of Technology,Guilin 541004,China;Poly Changda Engineering Co.,Ltd.,Guangzhou 510000,China;Southwest Nonferrous Kunming Exploration Surveying and Designing(Institute)Inc.,Kunming 650217,China)

机构地区：[1]桂林理工大学广西岩土力学与工程重点实验室,广西桂林541004 [2]保利长大工程有限公司,广州510000 [3]西南有色昆明勘测设计(院)股份有限公司,昆明650217

出　　处：《桂林理工大学学报》2024年第2期239-247,共9页Journal of Guilin University of Technology

基　　金：国家自然科学基金项目(11962004);广西自然科学基金项目(2017GXNSFAA198215)。

摘　　要：含水合物土体的一维压缩特性对分析含水合物地层变形特性具有重要意义。基于南海神狐海域SH3钻孔的沉积物物理性质,人工配制了细粒土作为水合物赋存介质制作了含水合物土试样,并开展一维压缩试验,研究了水合物饱和度与环境温度对含水合物土压缩变形的影响规律。结果表明:随着水合物饱和度增大与环境温度降低,含水合物土越难被压缩,可压缩性变小;水合物饱和度与环境温度对屈服后压缩指数和回弹指数影响趋势不明显,但水合物饱和度的提高与环境温度的降低会明显减小屈服前压缩指数和增大先期固结压力;水合物的形成填充了孔隙空间并胶结土体颗粒,而环境温度降低使得胶结作用更为显著,土体颗粒及水合物颗粒难以发生移动重排,导致土体难以被压缩,也使其整体结构性越来越强,先期固结压力增加。根据分析结果,提出了先期固结压力随水合物饱和度变化的经验关系式,给出了一维压缩曲线的数学表达式。The property of one-dimensional compression for hydrate-bearing soil is an important means to analyze the deformation of hydrate-bearing strata.Based on the physical properties of sediments from SH3 boreholes in Shenhu sea area of the South China Sea,fine-grained soil was artificially prepared as hydrate occurrence medium,and hydrate-bearing soil samples were formed and one-dimensional compression tests were carried out.The effects of hydrate saturation and ambient temperature on the compression deformation of hydrate-bearing soil were studied.The test results show that as the saturation of hydrates increases and the ambient temperature decreases,the soil containing hydrates becomes more difficult to compress and its compressibility decreases.The influence of hydrate saturation and ambient temperature on pre-yield compression index and swelling index is not obvious,but the increase of hydrate saturation and decrease of ambient temperature will significantly reduce the pre-yield compression index and increase the preconsolidation pressure.The formation of hydrate fills the pore space and solidifies soil particles,but the decrease of environmental temperature makes the cementation more obvious,and it is difficult for the soil particles and hydrate particles to move and rearrange,so the soil is difficult to be compressed and the overall structure becomes stronger and stronger as the pre-consolidation pressure increases.According to the analysis,the empirical relationship between the preconsolidation pressure and the hydrate saturation is proposed,and the mathematical expression which can effectively describe the one-dimensional compression curve is given.

关 键 词：含水合物土 一维压缩 先期固结压力 压缩指数 回弹指数 

分 类 号：TU43[建筑科学—岩土工程]