On July 25, at the comprehensive upgrade and renovation site of the Shifangyu Mountain and Laohudong Mountain tunnels on the South Second Ring Expressway in Jinan, after three months of construction, the tunnels have completed the spraying of the "Spring City Blue" topcoat, the installation of internal main lighting, and the installation of steel stone panels on the inner side walls, with the "Spring City Blue, Starry Sky Ceiling" splendor beginning to take shape.

The Shifangyu Mountain and Laohudong Mountain tunnels are important components of the South Second Ring Road Expressway and were completed and opened to traffic in 2015. This construction project carries out comprehensive upgrading and renovation in terms of defect treatment, noise reduction renovation, lighting enhancement, and traffic environment.

Since the start of construction, without affecting the normal passage of citizens, construction has been carried out at night, with temporary traffic diversion and control implemented in three phases, maximizing the principle of "yielding the road to the people."

The internal space of the tunnel is limited, vehicle traffic volume is high, and there are numerous equipment pipelines, making it impossible to completely close off traffic, so construction is relatively difficult. The project department optimized the design plan, adopting refined construction measures such as parallel construction by sections, flow-line operations by segments, and adequate provision of small equipment, reasonably arranging work procedures to ensure that defect treatment, steel stone panel installation, topcoat spraying, and other construction proceed to high standards.

The project innovates in design, abandoning the monotony and dullness of traditional tunnel decoration and incorporating modern aesthetics and regional cultural elements. In the lighting renovation of the tunnel project, innovative design concepts, advanced technology, and regional cultural characteristics are integrated to improve the lighting environment inside the tunnel and enhance the comfort and safety of citizens' travel. In the tunnel noise reduction design, an innovative scheme combining sound barriers with membrane structures is adopted for the first time, integrating the two technical means of sound absorption and sound insulation to effectively reduce noise at the open sections of the tunnel. In the intelligent interactive design of the tunnel, a comprehensive tunnel management and control cloud platform is introduced, achieving seamless linkage and efficient operation of multiple key systems within the tunnel, which not only improves the daily operational efficiency of the tunnel but also enhances response capability in emergency situations.