(1. Key Laboratory of Transportation Tunnel Engineering (Southwest Jiaotong University), Ministry of Education, Chengdu 610031, China; 2. Sichuan Transportation Investment Group Co., Ltd., Chengdu 610000, China; 3. Sichuan Tibetan Area Expressway Co., Ltd., Chengdu 610000, China; 4. China Railway Eryuan Engineering Group Co., Ltd., Chengdu 610031, China)
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