南黄海大丰海域海洋土动剪切模量和阻尼特征研究  

Study on dynamic shear modulus and damping characteristics of Marine soil in Dafeng Sea area,South Yellow Sea

作　　者：陈蕾[1] 冀卫东 陶小三[3] 李荣富 王海波[1] 朱海伦 CHEN Lei;JI Weidong;TAO Xiaosan;LI Rongfu;WANG Haibo;ZHU Hailun(College of Civil Engineering,Nanjing Forestry University,Nanjing 210037,China;Goldwind Technology Co.Ltd.,Beijing 100176,China;Jiangsu Institute of Earthquake Engineering,Nanjing 210014,China)

机构地区：[1]南京林业大学土木工程学院,南京210037 [2]金风科技股份有限公司,北京100176 [3]江苏省地震工程研究院,南京210014

出　　处：《林业工程学报》2025年第2期156-164,共9页Journal of Forestry Engineering

基　　金：国家自然科学基金(52078187);江苏省自然科学基金(BK20150885);江苏高校优势学科建设工程资助项目(PAPD)。

摘　　要：为探究南黄海大丰地域海洋土的动模量阻尼特性,对该海域0~200 m深度范围内各地层土类开展GDS循环三轴测试研究。结果表明:该区域土动剪切模量和阻尼各个应变下分布基本满足正态分布,模量比变异系数与剪应变之间呈正相关,而阻尼比则相反,总体上阻尼比的变异性比模量更突出,土类对变异性有显著影响。对比我国其他海域海洋土,该海域各地层土剪切模量总体不高,阻尼则在1×10^(-6)~5×10^(-4)应变范围内发展缓慢,5×10^(-4)以后发展较快导致最终阻尼偏大,相应G/G_(max)-γ、λ-γ曲线整体表现出较弱的非线性以及滞后性的区域动力特征。G_(max)随土层深度呈现出持续递增的趋势,且粉土的增长速率最大,埋深对南黄海大丰海域海洋土最大动剪切模量影响相对其他海域不显著。综合研究结果,给出了南黄海大丰海域典型地层海洋土不同埋深下的推荐值,为该海域内海洋建设工程的地震安全性评价工作以及未来海域地震区划的开展提供重要的借鉴与参考。In order to investigate the dynamic modulus and damping characteristics of marine soils in the Dafeng region of the South Yellow Sea.GDS cyclic triaxial tests were conducted on various soil layers within a depth range of 0-200 m.The results showed that the distributions of dynamic shear modulus and damping ratio of the soil in this region approximately followed normal distributions at all strains.The coefficient of variation of the modulus ratio exhibited a positive correlation with shear strain,whereas the damping ratio showed the opposite trend.In general,the variability of the damping ratio was more pronounced than that of the modulus,and soil type had a significant effect on this variability.In the four typical regional soils,they were ranked in the order of clay,sand,silt and sandy clayey interbedded soil.Compared with marine soils from other regions of China,the shear modulus of soils in this region was relatively low,while the damping ratio increased slowly in the strain range of 1×10^(-6)to 5×10^(-4),and more rapidly beyond this,resulting in higher final damping values.The corresponding G/G_(max)-γandλ-γcurves exhibited a weak nonlinearity and hysteresis,reflecting the regional dynamic characteristics.The G_(max)showed a consistent increase with depth,with the most significant growth rate observed in silty soils.The effect of depth on the maximum dynamic shear modulus in the Dafeng region was relatively less pronounced when compared with other regions.Based on these findings,the recommended values for the marine soils at different depths in typical strata of the Dafeng region were provided,offering valuable reference for seismic safety assessments of marine construction projects in this area and for future seismic zoning efforts.

关 键 词：海洋土 动剪切模量 阻尼比 动三轴试验 

分 类 号：TU443[建筑科学—岩土工程]