First Double-track Metro Section in Karst Area of Spring Field in China Completed

　　On April 27, the cutter head of the shield machine "Quanxing No.2" broke through the soil at the foot of Mount,Qianfoshan, and the double-track metro section between Quancheng Park Station and Mount. Qianfoshan Station of Jinan Metro Line 4 was completed. This section is the first metro section in China to traverse karst area of spring field.