论文部分内容阅读
在TBM施工隧洞工程中,装配式管片的科学设计及施工质量控制是一个重要技术问题,国内外对存在断层破碎带下的隧洞管片施工期受力特征研究不多。文章以青海省引大济湟调水干渠引水隧洞中断层破碎带注浆加固后的管片结构应力计算为实例,采用弹塑性有限元法,按照Drucker-Prager屈服准则,分析了对断层破碎带进行灌浆加固后的管片受力改善情形。研究表明:注浆加固后,含断层破碎带围岩形成一个弹塑性承载环,可以增强围岩的自承能力并抑制其屈服区的扩展,从而改善管片受力状态;对断层破碎带进行加固时,必须达到一定注浆范围才能有效改善管片受力条件,同时存在断层破碎带注浆处理的经济半径,即若注浆范围过多地超过此经济半径则难以进一步改善管片受力条件。
In the TBM construction tunnel project, the scientific design and construction quality control of the assembled pipe segment is an important technical issue. At home and abroad, there is not much research on the mechanical characteristics of the tunnel segment under the fault fracture zone during construction. In this paper, the stress calculation of the pipe structure after grouting reinforcement in the diversion tunnel of the diversion tunnel of Qingjian Hydropower Station is carried out. The elasto-plastic finite element method is used to analyze the stress distribution of the fault fracture zone according to the Drucker-Prager yield criterion After the grouting reinforced sheet stress to improve the situation. The results show that the surrounding rock of fault fracture zone forms an elasto-plastic bearing ring after grouting reinforcement, which can enhance the self-supporting capacity of surrounding rock and restrain the expansion of yield zone, so as to improve the stress state of the segment. In the process of reinforcement, it is necessary to reach a certain range of grouting to effectively improve the stress conditions of the pipe and the economic radius of the grouting treatment of the fault broken zone. If the grouting range exceeds the economic radius, it is difficult to further improve the stress of the pipe condition.