On August 11, the third-section roof slab of No. 1 evacuation exit and No. 2 ventilation pavilion at Xiacun Station in Work Area 4 of the Phase II (North Extension) Project of Shenzhen Metro Line 13 was completed, marking that the ** work area of the project has completed full capping of the main and ancillary structures, and is making every effort to accelerate the final stage of civil engineering construction.

The geological structure of the construction section is complex. To ensure smooth and orderly tunneling, the command headquarters, together with the work area project department, adopted the slurry balance shield half-chamber compressed air tunneling technology, making the slurry shield suitable for both sandy gravel strata and cohesive soil strata. The mode conversion time for a 6-meter-class slurry shield requires only 30 minutes. Compared with traditional slurry balance shields, this greatly increases the tunneling speed of the shield machine in clay strata, reduces the probability of clogging and chamber blockage, and achieves "one machine, multiple uses," laying a solid foundation for high-quality project construction.

During the construction process, the project department innovatively adopted concrete anti-cracking optimization design technology. In response to Shenzhen's special environment of high temperature and high salinity, and in combination with construction conditions and service environment factors, the concrete mix proportion for the station structure was improved, effectively enhancing the compressive and anti-cracking performance of the concrete and reducing the shrinkage rate. The number of cracks was reduced by 80%, promoting the development of management toward greater technological sophistication and precision.

The construction section is characterized by high groundwater levels, shallow burial depth, and great difficulty in structural seepage and leakage control. The use of traditional waterproofing methods has problems such as long construction cycles and low efficiency. Facing these difficulties, the work area project department took the initiative and adopted grouting technology with stronger applicability and higher efficiency. By applying back-wall grouting waterproofing technology to the main structure of the underground station, a two-component grouting machine was used to carry out systematic grouting of the main structure. This has strong applicability, high grouting efficiency, and continuous and uniform grout output, effectively improving the waterproofing effect and overcoming the shortcomings of traditional main structure leakage-repair construction, such as long construction time and low construction efficiency, while saving about 70% of labor.