On May 5, the section of the Luding–Shimian Expressway scheduled to open to traffic in 2024 reached an important milestone: the first extra-long tunnel, the Baicaoping Extra-long Tunnel, achieved double-tube breakthrough, sounding the "charge call" for the 33-kilometer Shimian section to be completed and opened to traffic within the year.

The Baicaoping Tunnel is located in Wanggangping Township, Shimian County, with a left tube 3,388 meters long and a right tube 3,372 meters long. The tunnel lies near the Xianshuihe fault zone, where seismic activity is intense, and its construction faces numerous difficulties such as broken surrounding rock, water inflow, and extremely complex geological conditions, posing considerable construction difficulty, environmental and water-conservation challenges, and safety risks. The project is invested in by Sichuan Road and Bridge Group's Tibetan Plateau Expressway Luding–Shimian Company and constructed by Sichuan Road and Bridge Communications Construction Group.

Facing many severe challenges, the Luding–Shimian Company used advanced geological forecasting and geological sketching of the tunnel face to predict surrounding rock conditions in advance and dynamically adjust support parameters, effectively improving construction safety; it adhered to "zero-excavation" tunnel entry, greatly protecting the surrounding ecological environment; and it optimized resource allocation, implemented the concept of "mechanization replacing workers and intelligent systems reducing personnel," and invested heavily in new equipment, new processes, new methods, and new materials, completing the tunnel breakthrough target 15 days ahead of schedule.

The smooth double-tube breakthrough of the Baicaoping Tunnel has opened up the construction access route from the Liyue Tunnel to the Xiaotianwan Tunnel on the Luding–Shimian Expressway, avoiding the traffic risks on National Highway G662 during the flood season. Next, while ensuring safety and environmental protection, the Luding–Shimian Company will continue to rapidly advance construction, muster all its energy, and go all out to ensure the project is completed and opened to traffic on schedule.

The Luding–Shimian Expressway is more than 96 kilometers long in total. The project starts at Sanggangping in Luding County and ends at Dashanshu in Shimian, connecting the Ya'an–Kangding and Ya'an–Xichang expressways. It is an important component of the Sichuan Provincial Expressway Network Plan (2019–2035). Once the entire line is completed and opened to traffic, the travel time from Luding to Shimian will be shortened from the current 3 hours to 1 hour.