基于微变形控制要求的地铁车站基坑钢支撑预加轴力研究

Study on Steel Support Pre-applied Axial Force of Metro Station Foundation Pit Based on Micro Deformation Control

地铁车站基坑钢支撑合理取值范围的确定对于围护结构变形控制效果及其受力安全具有重要意义。以深圳地铁12号线和平站下穿穗莞深城际铁路高架结构段基坑工程为依托,通过数值模拟和理论分析,对基于地连墙变形、地连墙受力、钢支撑受力及墩台位移等不同控制对象的钢支撑预加轴力取值范围进行了研究。结果表明,地铁车站基坑钢支撑预加轴力的合理取值范围宜为钢支撑设计轴力的0.5~0.7倍。

The determination of reasonable value range of metro foundation pit steel support is of great significance to the enclosure structure deformation control effect and stress safety.Based on the project of Heping Station of Shenzhen Metro Line 12 under-crossing Guangzhou-Shenzhen Intercity Railway elevated structure section foundation pit,through numerical simulation and theoretical analysis,the value range of steel support pre-applied axial force based on different factors including diaphragm wall deformation and stress,steel support stress and pier displacement is studied.Results show that the reasonable value range of metro foundation pit steel support pre-applied axial force should be 0.5 to 0.7 times of steel support designed axial force.