摘要
根据六盘山隧道二次衬砌存在的强度、厚度等问题,采用MIDAS NX大型有限元软件—MIDAS NX仿真技术,对代表性缺陷截面的应力进行了分析,再进行安全性、可靠性检验,最终对其质量安全进行了评价。研究结果表明:二次衬砌在强度不足段的最大压应力为19.78 kPa,比混凝土的抗压强度低;由于拱顶部分二衬厚度不够,致使初支应力状况变差,拱顶到拱腰部位的初支轴力显著增大,但增加后的初支内力仍未超过混凝土强度设计值。此外,也会导致二次衬砌应力状态劣化,表现为拱顶至拱腰位置二次衬砌中的最大主应力、最小主应力明显增大,但增长后的二衬应力仍未超过混凝土强度设计值。因此,判定缺陷断面支护结构满足安全要求。
Based on the strength,thickness and other issues of the secondary lining of the Liupanshan tunnel,the stress of representative defective section is analyzed by using the MIDAS NX large-scale finite element software-MIDAS NX simulation technology,followed by safety and reliability tests.Finally,its quality and safety are evaluated.The research results show that:the maximum compressive stress of the secondary lining in the section with insufficient strength is 19.78 kPa,which is lower than the compressive strength of concrete;due to insufficient thickness of the secondary lining at the arch crown,the initial support stress condition deteriorates,and the initial support axial force from the arch crown to the haunch significantly increases.However,the increased initial support internal force still does not exceed the design value of concrete strength.In addition,it can also lead to a deterioration of the stress state of the secondary lining,manifested as a significant increase in the maximum and minimum principal stresses in the secondary lining from the arch crown to the haunch,but the increased secondary lining stress still does not exceed the design value of concrete strength.Therefore,it is determined that the support structure of the defective section meets the safety requirements.
作者
钟玉刚
芦浩伦
Zhong Yugang;Lu Haolun(China Railway Construction Bridge Engineering Bureau Group Co.,Ltd.,Tianjin 300300,China;Colledge of Civil Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,China;Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering,Xi'an 710055,China)
出处
《北方交通》
2023年第6期79-83,共5页
Northern Communications
