About the author:

1. CCCC （Guangzhou） Co., Ltd., Guangzhou, Guangdong 511400, China;2. China Municipal Engineering Central South Design and Research Institute Co., Ltd., Wuhan,Hubei 430010, China; 3. Guangdong Engineering Technology Research Center of Municipal Rail TransitLean Construction, Guangzhou, Guangdong 510220,China; 4. China 19th Metallurgical Group Co., Ltd.,Chengdu, Sichuan 610031, China

Abstract:

Taking a subway station foundation excavation project in Xining City as the researchbackground, this paper employs a numerical simulation system to analyze the mechanical responsepatterns of the supporting structure in deep foundation excavations in arid regions under temperatureeffects. The influences of different environmental temperatures, retaining structure stiffness, elasticmodulus of steel struts, linear expansion coefficients, and strut lengths on the axial force of steel strutsare investigated. The results indicate that an increase in environmental temperature leads to a significantrise in the axial force of steel struts,while an improvement in the concrete grade of the retaining structuregradually reduces the axial force. As environmental temperature increases, the growth of the elasticmodulus and expansion coefficient of steel struts further amplifies the axial force. When the steel strutlength reaches 63m, the temperature⁃induced axial force increment exceeds the code⁃specified limit,adversely affecting the stability of the foundation excavation. During excavation, the installation and pre⁃stressing of steel struts should be avoided under extreme temperature conditions. Steel materials withlower thermal expansion coefficients should be prioritized to mitigate the unfavorable effects of thermal deformation on the support system.