长江漫滩区超深基坑预降水试验及分析

TEST AND ANALYSIS ON PRE-PRECIPITATION OF ULTRA-DEEP FOUNDATION PIT IN YANGTZE RIVER FLOODPLAIN AREA

江南工作井超深基坑工程临近长江且近接既有青奥隧道综合体,为确保降水方案满足开挖要求,在正式开挖:土方前,进行现场预降水试验,以指导后期开挖过程中的降水方案。分析可知,基坑内及两墙间降水对坑外水位影响较小,表明基坑止水帷幕质量较好,获取的降水参数和试验数据可指导后期土方开挖过程中的降水施工。

The Jiangnan working well ultra-deep foundation pit project is close to the Yangtze River and close to the existing Youth Olympic Tunnel Complex.To ensure that the precipitation plan meets the excavation requirements,a field pre-dewatering test is carried out before the earthwork is officially excavated to guide the subsequent excavation process Precipitation scheme.The analysis shows that the dewatering in the foundation pit and between the two walls has little effect on the water level outside the pit,indicating that the quality of the water-stop curtain of the foundation pit is good.The obtained precipitation parameters and test data can guide the dewatering construction in the later earth excavation process.