As the Year of the Ox begins with auspicious prospects and swallows dance under a bright sky, good news arrives again from Foshan Metro Line 3 at the start of 2021. On January 12, accompanied by the roar of the shield machine's cutterhead rotating and breaking through the soil, the shield on the left tunnel line of the Guicheng Station–Nanhai Square Station section of the Line 3 project successfully emerged, marking the first tunnel to break through in the central area of Guicheng in Nanhai District.

Guicheng Station is an interchange station between Foshan Metro Line 3 and the Guangfo Line, located at the intersection of Nanhai Avenue and Nangui East Road. Surrounded by high-rise buildings, it is a densely populated area of Nanhai District.

The tunnel of the Guicheng Station–Nanhai Square Station section runs along Nanhai Avenue, where surface traffic is busy. Along the route there are various pipelines for water supply, gas and communications, and multiple buildings and structures are adjacent on both sides, imposing high requirements for safety risk control. The geological conditions in this section are extremely complex. In a short span of 784 meters, the shield passes through unfavorable strata including full-face medium-coarse sand, the Chongleigang fault zone and protruding rock veins, strongly and moderately weathered argillaceous siltstone, and karst caves and limestone areas, making shield advancement extremely difficult.

To solve the shield advancement problems, the Construction Business Headquarters of Foshan Railway Investment Group faced the difficulties head-on, pooled collective wisdom, and organized participating units to hold multiple expert consultation and review meetings. After comprehensively comparing several construction schemes and adopting the best, it used new processes and methods such as liquid nitrogen ground freezing for the first time in the Line 3 project. During construction, it joined with the construction and supervision units in 24-hour duty shifts to safely open the chamber 150 times, ultimately successfully resolving the construction difficulties.

The pass is truly like iron, yet now we march forward from the start! At present, construction of the Line 3 project is in full swing. The smooth breakthrough of the left tunnel line in this section has strongly guaranteed the project construction schedule and also strengthened the confidence and determination of the vast number of builders to build Line 3 with guaranteed quality and quantity. Having accumulated valuable construction experience from the breakthrough of the left tunnel line in this section, Foshan Railway Investment Group will continue with meticulous planning and strict control, actively advance the construction of the right tunnel line of the Guicheng Station–Nanhai Square Station section, and achieve the goal of double-line tunnel breakthrough in this section as early as possible.