There are four shield interval tunnels of 15#~19# comprehensive shafts in the project of Shenzhen Line 14 Co-Construction Corridor 14GL-101 Bidding Zone 4. China Railway Shanhe invested two sets of φ8830mm composite soil-pressure-balance shield machines of the same specification and a whole set of shield construction management team. Among them, No.38 machine entered the site in September 2021 for downhole assembly, and made a big split start on October 21 of the same year, and after 233 days of days and nights, it broke through the ground on June 11, 2022, successfully completing its debut.

Tackling difficulties and setting up benchmarks

“The total length of the 18#~17# comprehensive well interval of this through is about 764m, close underneath the Ailian River box culvert and sewage lifting pumping station, and side through the northwest gate of Shenzhen Institute of Information Technology, and the construction stratum is mainly micro-weathering grey rock, crumbly strongly weathered sandstone and other strata, and there are many fracture zones and oversized volume of more than 10,000 cubic meters of dense karst strata, and a slight mishandling may occur. Ground subsidence, construction risk and difficulty can be imagined.” On-site construction personnel feedback, the interval shield starting well is also the smallest working well in the whole line 14 co-built pipeline corridor project, only about 28m long, which also brings a lot of challenges to the shield construction.

In view of these construction difficulties, China Railway Shanhe and the project team carried out fine control and implementation from the aspects of equipment selection, technical planning, construction management and parameter control, etc., which were highly evaluated by the owner in terms of construction quality, progress and ground settlement control, accumulating valuable experience for the construction of similar strata in the following years, and setting up a benchmark for the unfinished works of the project.

Continuously helping to build a beautiful Bay Area

Shenzhen Line 14 Common Pipeline Corridor 14GL-101 Bidding Zone 4 is a supporting project of Shenzhen's major project Metro Line 14, which provides an effective underground space for the normal operation of the subsequent Shenzhen Metro Line 14 and the storage and overhauling of various types of pipelines, and circumvents the drawbacks of the previous pipelines that need to be regularly excavated to carry out overhauling and affecting the traffic or people's livelihood, which is of great significance for the rational planning of the metro construction across the times in China. This is of great significance to the rational planning of China's subway construction across the times.

At present, more than 30 sets of shield machines of China Railway Shanhe have been deeply rooted in South China, spreading all over Guangzhou, Dongguan, Foshan, Shenzhen and other projects, showing a blossoming trend. Next, China Railway Shanhe will be more full of passion to meet the subsequent construction tasks and contribute to the construction of the beautiful Bay Area.