At 4:20 a.m. on September 12, with the smooth pouring of the final batch of concrete, all 615 cubic meters of concrete for the first section (axes 1-3) of the base slab at Xiaojie Station (axes 1-44) on the northern section of Tianjin Metro Line 4 were poured. At this point, all base slabs of the main foundation pit at Xiaojie Station (axes 1-44) have been completed, achieving closure of the foundation pit base. This also marks a phased victory in the project's main construction and lays a solid foundation for subsequent main works. Since the first base slab at Xiaojie Station (axes 1-44) was poured on May 28, all participating builders have strictly controlled whole-process supervision and construction safety and quality management, strictly followed construction standards, and completed each procedure with high quality. The entire project team optimized the construction organization plan, rationally allocated production resources, refined and quantified the project schedule, and raced against time, pushed progress, battled high temperatures, and fought through the flood season. The project company and the civil engineering Section 1 project department strictly adhered to the leadership shift system, with construction supervision and technical personnel providing 24-hour on-site guidance. All staff charged to the front line, kept watch on the front line, and raced on the front line. After more than three months, the base slab pouring task was completed on September 12, successfully achieving closure of the foundation pit base.