| 摘要: |
| 【目的】针对含水疏松砂岩冻结法施工问题，对冻结帷幕进行应力应变分析，为同类岩土的施工和设计提供依据，也为冻结法施工多场耦合数值模拟奠定基础。【方法】以甘肃引洮一期工程7#隧洞为例，在综合考虑隧洞掘进对温度场、位移场和应力场影响的基础上，依托热学理论及有限元分析软件ANSYS，对隧洞进行热-结构耦合三维数值模拟分析。【结果】通过对隧洞进行热-结构耦合三维数值模拟分析，得到隧洞冻结与开挖过程中冻结帷幕厚度为3.3 m，温度场平均温度为-13.3 ℃，冻土帷幕最大沉降量为2.46 mm，满足设计要求；同时通过对最危险断面的应力与应力强度进行对比，得到Y方向应力和切应力安全系数分别为5.57和7.95，大于规范中供设计时的最大参考值2.0。【结论】对于含水疏松砂岩冻结法施工，温度和结构具有相关性，热-结构耦合分析相比结构分析和热应力分析精确度更高。 |
| 关键词: 隧道工程 含水疏松砂岩 冻结帷幕 热-结构耦合分析 安全系数 |
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| 基金项目:国家批复引洮工程科学研究试验基金项目（2011CB403305） |
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| Numerical analysis of frozen construction in water bearing loose sandstone tunnel based on thermal-structure coupling |
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LU Lijuan,XU Jian,LIU Jinyun,et al
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| Abstract: |
| 【Objective】Aiming at the problems in water bearing loose sandstone freezing construction method,this study analyzed the stress and strain to provide the basis for the design and construction of similar rock and soil and multi-field coupling numerical simulation. 【Method】In consideration of tunnel temperature field,displacement field and stress field of the foundation,the thermal structure coupling three dimensional numerical simulation of 7# tunnel of Gansu Yintao project was conducted based on heat transfer theory and finite element analysis software ANSYS. 【Result】Through the thermal structure coupling three-dimensional numerical simulation of tunnel,following results were obtained:freezing curtain wall thickness 3.3 m,average temperature of temperature field -13.3 ℃,and maximum settlement of frozen soil curtain 2.46 mm.All the results met the design requirements.The safety factors of stress and shear stress in Y direction were 5.57 and 7.95 comparing with the stress and stress intensities of the most dangerous section,which were greater than the maximum reference value of 2.0. 【Conclusion】Temperature and structure were related in freezing construction of water bearing loose sand. Compared with the structural analysis and thermal stress analysis,the thermal structural coupling analysis was more accurate. |
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