GENEVA, Nov. 23 -- CHINA RAILWAY 21ST BUREAU GROUP FIFTH ENGINEERING CO., LTD. (877 Wenchang RoadYongchuan District, Chongqing 402160), 中铁二十一局集团第五工程有限公司 (中国重庆市永川区文昌路877号) filed a patent application (PCT/CN2024/103259) for "CURTAIN GROUTING REINFORCEMENT METHOD FOR TUNNEL GROUP IN DEEP BACKFILL AREA, AND REINFORCEMENT EFFECT ASSESSMENT METHOD" on Jul 03, 2024. With publication no. WO/2025/236371, the details related to the patent application was published on Nov 20, 2025.
Notably, the patent application was submitted under the International Patent ...