摘要
[目的]为探究原位状态下海涂围垦区土壤强度特性与其孔隙特征之间的关系。[方法]以江苏省沿海滩涂不同围垦区土壤为研究对象,通过现场十字板剪切试验和CT扫描技术分析土壤结构与土壤原位抗剪强度(C_(u))和灵敏度(S_(t))之间的关系。[结果]滨海(BH)和如东(RD)处S_(t)为1.3~5.4,属于中敏感(2~4)至敏感(4~8)范围,但其扰动土的S_(t)在不同深度和围垦年限下无明显变化。相比之下,东台(DT)地区扰动土的S_(t)差异显著,其各土层深度的S_(t)值均高于BH和RD,其中DT1处S_(t)最高,BH3处最低。土壤力学性质分析表明,土壤体积质量(CD)、黏粒质量分数与C_(u)呈正相关(r=0.657,0.782,p<0.05),而土壤孔隙度与之负相关(r=-0.529,-0.414,p<0.05)。土壤灵敏度(S_(t))与分形维数(FD)和孔隙数量(NOP)呈显著负相关(r=-0.611,p<0.05)。在回归分析中进一步揭示C_(u)与土壤孔隙度呈负相关且S_(t)与NOP符合对数递减关系。主成分分析中第1主成分(PC1)主要由孔隙数量、分形维数和黏土质量分数主导,PC2以C_(u)和CD为主,PC3则受孔隙度和土体抗剪强度共同驱动,这些指标共同强调土壤孔隙结构和物理性质在抗剪强度评价中的重要性。[结论]研究结果为深入理解海涂围垦区土壤特性提供科学依据,对滨海地区工程建设稳定性、边坡稳定性、土壤抗侵蚀能力评估和植物生长条件分析等研究提供重要参考,有助于推动沿海地区农业的可持续发展。
[Objective]To explore the relationship between the characteristics of soil strength and soil pore in the tidal flat reclamation areas under in-situ conditions.[Methods]Taking the soils in different reclamation areas of the coastal tidal flats in Jiangsu Province as the research object,the relationships among soil structure,in-situ soil shear strength(C_(u))and sensitivity(S_(t))were analyzed through in-situ vane shear tests and CT scanning technology.[Results]The S_(t)values in Binhai(BH)and Rudong(RD)were between 1.3 and 5.4,falling within the range from medium sensitivity(2-4)to sensitivity(4-8).However,for the disturbed soil in these two places,the S_(t)values showed no significant changes under different depths and reclamation years.In contrast,the S_(t)values of the disturbed soil in Dongtai(DT)varied significantly.The S_(t)values in each soil layer were higher than those at BH and RD.Among them,the S_(t)value at DT1 was the highest,and the S_(t)value at BH3 was the lowest.The analysis of soil mechanical properties indicates that there was a positive correlation between soil bulk density,clay particle content and C_(u)(r=0.657 and 0.782,p<0.05),while there was a negative correlation between soil porosity and C_(u)(r=−0.529 and−0.414,p<0.05).In addition,there was a significant negative correlation between soil sensitivity(S_(t))and fractal dimension(FD),pore number(NOP)(r=−0.611,p<0.05).In the regression analysis,it is further revealed that there was a negative correlation between C_(u)and soil porosity,and S_(t)and NOP followed a logarithmic decreasing relationship.In the principal component analysis,the first principal component(PC1)was mainly dominated by the pore number,fractal dimension and clay content.PC2 was mainly composed of C_(u)and bulk density,and PC3 was jointly driven by soil porosity and soil shear strength.These indicators jointly highlight the importance of soil pore structure and physical properties in the evaluation of shear strength.[Conclusion]This study provides a scientific basis for an in-depth understanding of soil characteristics in coastal reclamation areas and offers important references for research on the stability of engineering construction,slope stability,evaluation of soil erosion resistance,and analysis of plant growth conditions in coastal areas,which is helpful to promote sustainable development of agriculture in coastal areas.
作者
姜子煜
王洪德
孙枭沁
潘永春
唐胜强
佘冬立
无
JIANG Ziyu;WANG Hongde;SUN Xiaoqin;PAN Yongchun;TANG Shengqiang;SHE Dongli;无(College of Agricultural Science and Engineering,Hohai University,Nanjing 211100,China;School of Earth Sciences and Engineering,Hohai University,Nanjing 211100,China;College of Soil and Water Conservation,Hohai University,Nanjing 211100,China)
出处
《水土保持学报》
北大核心
2025年第3期147-153,共7页
Journal of Soil and Water Conservation
基金
国家自然科学基金项目(42307398)。
关键词
土壤抗剪强度
孔隙特征
CT扫描
主成分分析
soil shear strength
pore characteristics
CT scanning
principal component analysis
