【摘要】 采用“地连墙+内支撑”支护的基坑施工时常出现接缝渗漏水的现象，已有研究往往将渗漏原因归咎于接缝质量问题，忽略了支撑轴力所引起接缝错动带来的影响。依托天津地铁11号线一经路地铁站基坑工程进行大型现场试验，通过改变支撑轴力大小观察接缝两侧地连墙的变形差异，进一步通过数值模拟深入研究地连墙接缝错动的形成机理及发展过程。结果表明：地连墙接缝处存在较明显的错动，沿地连墙深度方向错动极值达到14.89 mm,这是由于接缝两侧支撑不同步架设造成了接缝两侧地连墙变形差异导致的，支撑延后架设一侧变形相比支撑同步架设一侧变形增大25%～50%;此外，支撑加载顺序不同也会对接缝错动产生一定影响。由此针对局部支撑延后架设的数量及位置，制定了最利于接缝错动控制的架设方案，并提出了调整接缝两侧支撑预加轴力和及时架设下层支撑两种过程控制措施，以减小接缝错动。更多还原

【Abstract】 In foundation pit engineering supported by “diaphragm walls with internal supports”, joint leakage frequently occurs. Existing studies often attribute leakage causes to joint quality defects while neglecting the impact of joint dislocation induced by support axial forces. Large-scale field tests and numerical simulations were performed to investigate the formation mechanism and development process of joint dislocation at the Yijing Road Station project of Tianjin Metro Line 11. On-site monitoring was conducted, and displacement patterns were analyzed. Results reveal that significant dislocation exists at joints, with maximum vertical displacement reaching 15 mm along diaphragm wall depth. This phenomenon primarily stems from differential deformations between adjacent diaphragm wall panels caused by asynchronous installation of corresponding supports. The deformation in panels with delayed support installation increases by 25%～50% compared to those with simultaneous support installation. Furthermore, the sequencing of support loading demonstrates measurable effects on joint dislocation characteristics. Based on these findings, an optimal erection scheme is proposed regarding the quantity and positioning of locally delayed supports for dislocation mitigation. Two process control measures are recommended: adjusting pre-applied axial forces on adjacent supports and timely installation of lower-level supports. These countermeasures effectively reduce joint dislocation through coordinated deformation control during construction phases.更多还原