基于横观各向同性的土工格栅增强地基力学特性研究Transverse isotropy-based study on mechanical characteristics of geogrid reinforced foundation
彭木文,左双英,杨朵环,杨国生,莫云川
摘要(Abstract):
【目的】土工格栅加筋地基在水利、建筑、交通等工程应用广泛,其竖直方向和水平方向的力学特性是值得关注的焦点。为研究不同加筋间距、层数对土工格栅加筋地基竖向和水平向承载特性的影响,【方法】通过物理模拟浅层平板载荷试验,将土工格栅加筋地基视为横观各向同性介质,结合复合材料力学理论推导出了弹性参数的求解方法,同时考虑地基横观各向同性特征计算了竖向附加应力及沉降量。【结果】结果显示:400 kPa可作为地基极限荷载值,加筋5层、7层、16层在相同沉降位置的地基承载力分别提高了26%、39.2%、63.5%;在相同挡墙高度107 cm处,加筋5层、7层、16层工况相比无加筋工况水平位移减少了59%、66%、85%。【结论】结果表明:土工格栅加固地基后对土体的变形模量、剪切模量增强作用显著,而竖向泊松比变化较不明显;加筋地基的水平、竖向变形模量分别与加筋率之间存在较好的线性关系,采用横观各向同性模型推导计算的附加应力值接近试验值,计算的沉降量与试验值误差较小。研究成果可为类似实际工程设计提供一定的理论依据。
关键词(KeyWords): 加筋地基;横观各向同性;浅层平板载荷试验;附加应力;地基沉降
基金项目(Foundation): 国家自然科学基金(42167025);; 贵州省科学技术厅社会发展科技攻关项目(黔科合支撑[2017]2866)
作者(Author): 彭木文,左双英,杨朵环,杨国生,莫云川
DOI: 10.13928/j.cnki.wrahe.2023.03.012
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