高强度灌浆料在地铁基坑钢支撑围檩体系中的运用与研究

Application and Research of High Strength Grouting Material in Steel Support Purlin System of Subway Foundation Pit

上海轨道交通14号线豫园车站主体围护为65 m超深铣接头地下连续墙,坑内设5道钢支撑+钢围檩支撑体系及4道混凝土支撑,基坑开挖深度36 m,且周边敏感建筑众多,基坑围护变形控制要求极高。以此为例,为提高钢支撑体系有效性并抑制基坑变形,在钢支撑架设实施过程中采用高强度灌浆料代替普通细石混凝土进行钢围檩与地下连续墙间隙填充。结果证明,高强度灌浆料的强度发展及填充密实度效果理想,且有效提高了支撑体系对基坑变形控制的效果。

The main enclosure of Yuyuan Garden Station of Shanghai Metro Line 14 is 65 m ultra deep milling joint underground diaphragm wall.There are 5 steel supports+steel purlin supporting system and 4 concrete supports in the pit.The excavation depth is 36 m,and there are many sensitive buildings around,so it is extremely important to control the deformation of foundation pit support.Taking this as an example,in order to improve the effectiveness of the steel support system and restrain the deformation of the foundation pit,the high strength grouting material is used to fill the gap between the steel purlin and the underground diaphragm wall instead of the ordinary fine aggregate concrete.The results show that the effect of strength development and filling density of high strength grouting material is ideal,and the effect of support system on deformation control of foundation pit is effectively improved.