Zhengzhou Zhongzhou Avenue Tunnel is the longitudinal axis of the city’s downtown expressway system. It has the biggest section of a rectangular pipe jacking tunnel in the world. Since 1999, STEC has put rectangular pipe jacking technology into tunnel construction. The conduit jacking construction technology has a higher utilization rate of space with shallow overburden and low construction cost. These advantages make conduit jacking construction technology favorable for underground construction in big cities.

The construction of Zhengzhou Zhongzhou Avenue Tunnel consists of four rectangular pipe jacking tunnels through the use of a large section pipe jacking machine (10.4 m * 7.5 M). STEC managed to finish the first 110 meters long extra large section rectangular pipe jacking in China without disturbing the ground transportation, underground lines or pipes. The land subsidence was controlled in less than 3 centimeters. At the same time, in view of the special section structure of conduit jacking, the tunnel has a 35% higher utilization rate of space than a round section tunnel, reducing the depth of tunnel burial.

Till dare, among the finished rectangular pipe jacking tunnels, the biggest width is 6 meters like a pavement. STEC’s domestically designed 10 meters’ width tunnel is the first example in the world. It subverted the concept of city road design and construction. It is poised to become one of the best options of city’s underground transportation and tunnel net construction.