CAJ | 학술논문

依托重庆新红岩隧道工程，选典型2层砌体结构进行隧道施工爆破振动激励的OMA试验，采用等效体积单元法建立能准确反映砌体结构真实动力特性的有限元模型；探讨砌体用不同材料模型所得分析频率与实测频率误差及二者振型相关性；据OMA试验模态参数，基于砌体与混凝土材料参数的结构固有频率灵敏度分析，选择合适的修正参数进行有限元模型修正研究。结果表明，二层砌体结构前4阶固有频率位于9～25 Hz；较用各向同性模型而言，砌体采用各向异性模型时计算所得前4阶频率与实测频率值更接近，振型相关性更好；修正有限元模型中材料密度、弹性模量、剪切模量后频率与实测频率间误差明显减小，结构模型动力特性更符合实际，正交各向异性材料模型修正最准确。
의탁중경신홍암수도공정，선전형2층체체결구진행수도시공폭파진동격려적OMA시험，채용등효체적단원법건립능준학반영체체결구진실동력특성적유한원모형；탐토체체용불동재료모형소득분석빈솔여실측빈솔오차급이자진형상관성；거OMA시험모태삼수，기우체체여혼응토재료삼수적결구고유빈솔령민도분석，선택합괄적수정삼수진행유한원모형수정연구。결과표명，이층체체결구전4계고유빈솔위우9～25 Hz；교용각향동성모형이언，체체채용각향이성모형시계산소득전4계빈솔여실측빈솔치경접근，진형상관성경호；수정유한원모형중재료밀도、탄성모량、전절모량후빈솔여실측빈솔간오차명현감소，결구모형동력특성경부합실제，정교각향이성재료모형수정최준학。
Based on the engineering background of New Hongyan Tunnel in Chongqing,an operational modal analysis was carried out on a typical 2-story brick masonry structure under tunnel blast excitation.An accurate finite element model which could reflect the actual dynamic characteristics of the brick masonry structure was built by using the representative volume element. Furthermore, the numerical structural natural frequencies and modal shapes were compared with the experimental modal data.According to the first four modal parameters obtained from the operational modal analysis (OMA ) and based on the structural natural frequencies sensitivity analysis of masonry and concrete material parameters,the appropriate modifying parameters were selected and the model of the brick masonry structure was updated.The first four natural frequencies of the brick masonry structure are in 9 ~25Hz.The analysed natural frequencies by using anisotropic model match much better with the experimental modal parameters than by using isotropic model for the brick masonry.Besides,the correlation between the analyzed and experimental modal shapes is good.After updating the parameters of density,elastic modulus and shear modulus in the finite element model,the errors between analyzed frequencies and experimental results are reduced,and the dynamic characteristics parameters of the model are more close to the true values.The updating of the finite element model by using orthogonal anisotropic model for masonry is more accurate.