New progress has been made in the construction of South Ping Phase III: 2 of the 3 tunnels have been excavated, and the last tunnel has less than 1 km remaining before full breakthrough. The project is expected to be completed and open to traffic this year, making it more convenient for Pingshan residents to travel to the city center.
The South Ping Phase III project spans Longgang District and Pingshan District. The road starts at the Hengping Interchange exit of the Shuiguan Expressway in the west and ends at Julong Road (the planned TianTou Interchange of the Outer Ring Expressway) in the east, with a total length of about 22.2 km. The section from the starting point to the Biling Industrial Zone utilizes the existing Xinhengping Highway for reconstruction, with a six-lane dual carriageway mainline about 8.5 km long. The section from Biling Industrial Zone to Julong Road is newly built, with an eight-lane dual carriageway mainline about 13.7 km long. The entire line is built to urban expressway standards. The project intersects with several major roads including the Shuiguan Expressway and Longgang Avenue (National Highway 205), and a total of 15 interchanges are set up along the entire line.
Among them, the section from Shuiguan Hengping Interchange to Zhongshan Interchange is the reconstruction section of Xinhengping Highway, with a six-lane dual carriageway mainline about 8.5 km long and a design speed of 60 km/h; the section from Zhongshan Interchange to the Outer Ring Expressway is newly built, with an eight-lane dual carriageway mainline about 13.7 km long and a design speed of 80 km/h. A total of 15 interchanges are set up along the entire line. The road is positioned as an urban expressway, with a total estimated investment of about 4.274 billion yuan. The Municipal Transport Commission Construction Center revealed earlier that South Ping Expressway Phase III is planned to be completed and open to traffic in 2018. Upon completion, it will form the second ring horizontal connection channel of Shenzhen together with Phase I and Phase II, connecting major functional groups such as Pingshan, Henggang, Longhua, Nanshan, and the western port area. At that time, it will take only about 1 hour to drive from Qianhai to Pingshan.
The substructures of project nodes such as Zhongshan Interchange, Hengkeng Reservoir Viaduct, Jinlong Interchange, Dashanpi Reservoir Bridges No. 1, 2, and 3, Malan Interchange, and Longping Interchange have been completed, and the superstructures are 85% complete. Bridge deck paving and crash barrier construction are underway. The project's 3 tunnels have a total length of 3,645 meters, of which 2,560 meters have been excavated. Among them, Tunnel No. 2 (450 meters) and Tunnel No. 3 (790 meters) have been holed through.
South Ping Phase III passes through environmentally sensitive areas such as water source protection zones and Malan Mountain Country Park, so the project has high environmental protection requirements. It adopts permeable pavement, which is one of the low-impact development technologies for roads. A test section of this technology has been set up at the Zhongshan Interchange section, utilizing the storage and buffering capacity of underground water storage volume to reduce the comprehensive runoff coefficient after road development. Combined with the greening of the interchange, a rainwater collection, treatment, and utilization system (for greening and landscape water) is set up to form ecological landscape nodes. Additionally, the newly built sidewalks along the entire line use green ecological "permeable ecological concrete pavement".
The South Ping Phase III alignment passes through Malan Mountain Country Park and a secondary water source protection zone. Based on comprehensive consideration of construction plans and ecological protection, Dashanpi Bridge No. 1 adopts a low-carbon and environmentally friendly new structure, the "multi-chord composite beam bridge", which is constructed without supports, featuring fast construction speed, minimal environmental damage, and harmony with the surrounding landscape.
The mainline bridge of Malan Interchange is a fully integral jointless beam bridge, eliminating the need for expansion joints and bearings. The smooth bridge deck greatly improves driving comfort, reduces vehicle impact, and enhances the seismic performance of the bridge. With no bearings and expansion joints, diseases originating from bearings and expansion joints are eliminated, and later maintenance costs are reduced. Within 200 meters of the left exit section of Dashanpi Tunnel No. 1 of South Ping Phase III, there is a high-pressure gas pipeline and an oil pipeline, and the surrounding rock strength is high, making blasting extremely difficult. To avoid endangering the safety of the pipelines, through research, the project adopted tunnel blasting control technology and successfully completed the blasting.