防灾减灾工程学报2024，Vol.44Issue(3)：535-543,9.DOI:10.13409/j.cnki.jdpme.20231130008
沉积方向对珊瑚砂动剪切模量及阻尼比的影响
Effect of Deposition Orientation on the Dynamic Shear Modulus and Damping Ratio of Coral Sand
摘要
Abstract
Coral sand in complex geological environments exhibits significant anisotropic characteris-tics,with the sedimentation direction of the particles significantly affecting its dynamic properties.Res-onant column tests with uniform consolidation were conducted on coral sand from Nansha Islands to explore the effects of the deposition orientations(φ)(the angle between the deposition plane and the horizontal plane)and the initial effective confining pressure(σ'0)on its dynamic shear modulus G and damping ratio λ.At a given φ,the rate at which G decreased with increasing shear strain amplitude ya increased with increasing σ'0.At a given σ'0,the rate at which G decreased with increasing γa first de-creased and then increased with increasing φ,with the G-γa curve reaching its lowest position at φ=60°.Furthermore,the maximum shear modulus(G0)exhibited an initial decrease followed by an in-crease as φ increased,and the influence of φ on G0 diminished with increasing σ'0.A modified Hardin's model,which incorporated the influence of φ and σ'0,was established.The deviations between the measured and predicted G0 values were within 10％.The G/G0-ya curve was insensitive to φ,with de-viations between the measured and predicted G values by both the modified Hardin's model and Da-videnkov's skeleton curve falling within 15％.A correction term considering the influence of φ was in-troduced into the damping ratio empirical model proposed by Cheng Guoxing et al.(2006),with the deviation between the predicted and measured λ values being less than 20％.关键词
珊瑚砂/原生各向异性/沉积角度/动剪切模量/阻尼比Key words
coral sand/inherent anisotropy/deposition orientation/dynamic shear modulus/damping ratio分类
建筑与水利引用本文复制引用
徐子皓,秦悠,马维嘉,陈国兴..沉积方向对珊瑚砂动剪切模量及阻尼比的影响[J].防灾减灾工程学报,2024,44(3):535-543,9.基金项目
国家自然科学基金项目(52278503,52208350)资助 （52278503,52208350）
