Research on Invasion Line Control of Deep Foundation Pit Diaphragm Wall Excavation Based on Space-time Effect

The study focuses on the management of deep foundation pit excavation, influenced by temporal and spatial factors, in the context of the challenging environmental circumstances posed by the high-water-level silty soft clay along the Yellow River's northern shore, as part of the Jinan urban rail transit initiative. The subsequent inferences have been made: (1) Throughout the digging phase, issues such as excessive digging and delays in installing steel reinforcements occur, while the subterranean diaphragm wall tends to shift significantly inward within the excavation area due to the disparity in pressure between the water and soil inside and outside. (2) During the building phase, managing wall distortion is imperative, and an enhanced preliminary force should be applied to the support's axial component at points of significant deformation, guaranteeing an excess coefficient for both the support rigidity and the continuous subterranean wall rigidity. (3) In the process of diaphragm wall grooving, if the quality of grooving is not good, the quality of grooving in some areas will be poor, and there will be more bulges and mud on the surface of the wall, which will cause some positions to invade the line. Throughout the building process, appropriate strengthening actions must be implemented to maintain the integrity of the grooving work.