The Qingdao – Rongcheng (shortened as Qing-Rong) intercity railway was completed and opened to traffic in December 2014. Integral-stretched plastic geogrid as reinforcement materials was used in reinforced soil embankment for the first time in the history of high-speed railway construction in China.
Qing – Rong intercity railway is an intercity railway connecting Qingdao, Yantai and Weihai in Shandong Province. The line runs from southwest to northeast of the province. It starts from Qingdao station in the South then to Rongcheng station in the East, with a total length of 316 km and a design speed of 250 km / h. The railway is the main section of Intercity Railway in Jiaodong Peninsula and also an integral part of the coastal channel of China’s high-speed railway network.
Two reinforced soil retaining wall test sections are located near Jimo station in Qingdao and Rongcheng station in Weihai separately. It is the first reinforced soil embankment project for high-speed railway in China. The maximum height of the reinforced soil retaining wall is 9.3m, and the total length of the retaining wall is 1100 M. Modular block facing is used in the project.
The application of reinforced soil embankment along Qing-rong Intercity Railway solves the problems of limited land occupation, large demolition difficulty and cost, and differential settlement, effectively shortens the project duration, reduces the project cost, and improves the coordination between the high-speed railway subgrade and the ecological environment along the line, which has been highly praised by experts in the industry.
In view of the novel application, China Railway Design Group Co., Ltd., together with Shijiazhuang Railway University and Qingdao Xuyu geotechnical materials Co., Ltd., has conducted a systematic and in-depth study on the test sections, which has yielded valuable outcomes.
The performance of the reinforced soil embankment has been satisfactory since the railway opened to traffic more than 7 years ago. Up to now, the research results of reinforced soil retaining wall of Qingrong intercity railway have been successfully applied to a number of reinforced soil retaining wall projects of Chengdu Kunming railway, Qingdao Dongjiakou port dredging railway, among others.
The E’GRID120RL geogrid used in the project is supplied by BOSTD Geosynthetics Qingdao Ltd.