【摘要】 采用等效截面法将隧道衬砌初期支护中的喷射混凝土和钢拱架等效为均质梁截面,基于有限元法,计算出衬砌结构的轴力、剪力和弯矩;根据承载力包络图法对隧道衬砌喷射混凝土、钢拱架以及二次衬砌的结构安全性进行评价。以某铁路隧道复合衬砌工程实例为研究背景,基于上述所提出的方法建立有限元数值计算模型,进行隧道衬砌受力特性研究与结构安全性评价。计算结果表明,二次衬砌混凝土强度等级不足是导致衬砌破坏的可能原因之一,计算所示的衬砌裂缝位置与实际工程一致,提高混凝土强度等级可有效控制复合衬砌结构的开裂。更多还原

【Abstract】 We apply the equivalent section method to consider the spray concrete and steel arch of primary support of tunnel lining as the homogenized beam section.Based on finite element method,the axis force,shear force and bending moment of lining are calculated.The structural safety of spray concrete,steel arch and the secondary lining are assessed by the envelope diagrams of bearing capacity.In view of a real composite lining project of railway tunnel,the model of tunnel lining is established by the presented method,and the safety evaluation and loading characteristics of the composite linings are conducted.The results show that the insufficient strength of secondary lining concrete may lead to lining cracks,and their calculated locations are in well conformity with the measured.The improvement of concrete strength can control the cracking of composite linings effectively.更多还原