Recently, with the successful breakthrough of the final tunnel working face, the left tube of Mamiashan Tunnel in Section TJ03 of the Expressway Sanmen Link Line was holed through, becoming the "first breakthrough" among the tunnels of the Expressway Sanmen Link Line. This achievement marks a breakthrough at a major key node and signifies that the construction of the Expressway Sanmen Link Line has entered the stage of accelerated assault.

The Expressway Sanmen Link Line is an important component of the first horizontal line in the "four vertical and three horizontal" expressway network of Taizhou's comprehensive transportation system. It starts on the east side of Shanghu Village, Zhuao Town, and ends on the northeast side of Nanxin Village, Jianjiao Town. The route generally runs east-west, passing through Zhuao Town, Tingpang Town, Haiyou Subdistrict, Hairun Subdistrict, and Jianjiao Town, with its terminus connecting to the Coastal Expressway. After the project is completed, Sanmen will form a two-vertical and one-horizontal H-shaped expressway network, enabling all 10 townships (subdistricts) in the county to access the expressway within 10 minutes.

At the construction site of the right tube of Mamiashan Tunnel, machinery is roaring, and workers are carrying out drilling operations to prepare for the next blasting. The left tube, which was holed through first, is also undergoing secondary lining simultaneously to meet the requirements of modern expressway tunnel construction.

It is understood that Mamiashan Tunnel is located in Yuanli Village, Hairun Subdistrict. The left tube is 1,870 meters long, and the right tube is 1,880 meters long. It is a two-way, two-tube, four-lane expressway tunnel with a design speed of 80 kilometers per hour.

Wang Zhongtao, deputy production manager of the TJ03 section project of the Expressway Sanmen Link Line, said: "The left tube of Mamiashan Tunnel is the first tunnel in the entire Sanmen Link Line to be holed through, which has brought great encouragement and confidence to the construction personnel. There are still 79.5 meters remaining on the right tube. Based on the current excavation rate of 7 meters per day, the full holing-through of the right tube is planned to be completed before the end of the month."

According to reports, after the overall holing-through of Mamiashan Tunnel, the transport distance for concrete materials and tunnel slag will be reduced from the original 8 kilometers to 4.6 kilometers, saving construction costs and bringing a positive impact on the later stages of the project.

"Next, our section will, with the tenacity of 'biting firmly onto the green mountain and never letting go,' base itself on the annual goals, take safety as the guarantee and quality as the core, scientifically control the construction schedule and important time nodes, and continue to comprehensively promote the project's construction and production with a high-quality posture," said Wang Zhongtao.