1, Guizhou Highway Engineering Group Co., Ltd
2. China Railway Second Bureau First Engineering Co., Ltd.
3. China Railway 10th Bureau Group Second Engineering Co., Ltd.
4. Zhejiang Hongtu Traffic Construction Co., Ltd..
5. China Railway Fifth Engineering Group First Engineering Co., Ltd.
6. Sichuan Wu Tong Road and Bridge Engineering Bureau
7. Guizhou Highway Engineering Group Co., Ltd.
8. Guizhou Highway Engineering Group Co., Ltd.
9. Guangxi Zhuang Autonomous Region Highway and Bridge Engineering Company
10, China Railway First Engineering Group Co., Ltd.
1 1, China Railway 17th Bureau Group Second Engineering Co., Ltd.
12, China Railway 16th Bureau Group Third Engineering Co., Ltd.
13, cccc second harbor engineering bureau co., ltd.
14, cccc second harbor engineering bureau co., ltd.
15, Haiwei Engineering Construction Co., Ltd.
16, Fourth Engineering Co., Ltd. of China Railway 11th Bureau Group
17, Anhui Highway and Bridge Engineering Company
18, Zhejiang Jiaogong Road and Bridge Construction Co., Ltd.
19, China Railway 20th Bureau group second engineering co., ltd.
20. Guizhou Highway Engineering Group Co., Ltd.
2 1, China Railway 12th Bureau Group Third Engineering Co., Ltd.
22. China Railway 17th Bureau Group First Engineering Co., Ltd.
23. Guizhou Highway Engineering Group Co., Ltd.
24. Guangxi Zhuang Autonomous Region Highway and Bridge Engineering Company
25. Guangxi Zhuang Autonomous Region Highway and Bridge Engineering Company
26. China Railway 14th Bureau Group Third Engineering Co., Ltd.
25. Guangxi Zhuang Autonomous Region Highway and Bridge Engineering Company