Journal of Hebei University of Engineering
1673-9469
2024
41
1
72
80,89
10.3969/j.issn.1673-9469.2024.01.010
article
大断面类矩形顶管注浆压力对管节损伤的影响分析
Analysis of the Influence of Grouting Pressure on Pipe Joint Damage in Large Rectangular Pipe Jacking
为探究大断面矩形顶管注浆压力波动及其控制边界难以确定的实际问题,依托南京某大断面类矩形顶管工程,借助理论分析、工程类比和数值模拟等方法,研究了顶板和侧壁局部憋压工况下,大断面类矩形管节结构的变形和损伤机制。通过分析矩形顶管管节受力特征,计算了大断面类矩形管节承受的外荷载,并采用ABAQUS有限元数值模拟软件内置的混凝土损伤塑性模型进行数值建模,研究不同注浆压力作用下钢筋混凝土管节损伤演化机制。结果表明:(1)注浆荷载作为可变荷载,对管节受力有明显影响,应将注浆压力纳入管节设计环节;(2)针对该工程,其理论注浆压力为0.311 MPa,考虑抑制背土效应的需要,应适当提高注浆压力,但必须控制在合理范围内;(3)从损伤演化的角度来看,注浆荷载达到0.6 MPa时,管节顶板的拉伸损伤已达到较高水平,因此,将0.6 MPa作为该工程的注浆压力预警指标,而0.9 MPa应作为注浆压力的控制指标。
In order to understand the influence mechanism of grouting pressure fluctuations on pipe joints in large cross-section rectangular pipe jacking, this paper relies on a large cross-section rectangular pipe jacking project in Nanjing, and uses research metho-ds such as theoretical analysis, engineering analogy, and numerical simulation to investigate the influence mechanism of grouting pressure fluctuations on the stress state of large cross-section rectangular pipe joint structures under local pressure suppression condit. The external loads of large cross-section rectangular pipe joints was calculated, and the concrete damage plasticity model built-in ABAQUS software was used for numerical modeling to study the damage evolution mechanism of reinforced concrete pipe joints under different grouting pressures. The results show that: (1) grouting load, as a variable load, has a significant impact on the stress distribution of the pipe joint, such that the grouting pressure should be included in the design of the pipe joint; (2) For this project, the theoretical grouting pressure is 0.311 MPa. In view of the need to suppress the carrying-soil effect, the grouting pressure should be appropriately increased, but it must be controlled within a reasonable range; and (3) From the perspective of damage evolution, when the grouting load reaches 0.6 MPa, the tensile damage to the top plate of the pipe joint has reached a high level. Therefore, 0.6 MPa is used as the grouting pressure warning indicator for this project, while 0.9 MPa should be used as a control indicator for grouting pressure.
大断面矩形顶管;钢筋混凝土管节;注浆压力;荷载;憋压;损伤分析
large-section rectangular pipe jacking;steel concrete pipe;grouting pressure;load;pre-ssure suppression;damage analysis
赵光,马鹏
ZHAO Guang, MA Peng
natural/article/abstract/20240110